[core] Change OverscaledTileID to also include a "wrap" value.

This prevents TilePyramid from sharing wrapped copies of tiles.
This is necessary because two wrapped tiles no longer share the same CollisionTile.

5 files changed, 588 insertions, 593 deletions

diff --git a/src/mbgl/algorithm/update_renderables.hpp b/src/mbgl/algorithm/update_renderables.hpp
index a9c348b538..0c2266ff47 100644
--- a/src/mbgl/algorithm/update_renderables.hpp
+++ b/src/mbgl/algorithm/update_renderables.hpp
@@ -31,7 +31,7 @@ void updateRenderables(GetTileFn getTile,
         assert(idealRenderTileID.canonical.z <= zoomRange.max);
         assert(dataTileZoom >= idealRenderTileID.canonical.z);
 
-        const OverscaledTileID idealDataTileID(dataTileZoom, idealRenderTileID.canonical);
+        const OverscaledTileID idealDataTileID(dataTileZoom, idealRenderTileID.wrap, idealRenderTileID.canonical);
         auto tile = getTile(idealDataTileID);
         if (!tile) {
             tile = createTile(idealDataTileID);
@@ -64,11 +64,11 @@ void updateRenderables(GetTileFn getTile,
             } else {
                 // Check all four actual child tiles.
                 for (const auto& childTileID : idealDataTileID.canonical.children()) {
-                    const OverscaledTileID childDataTileID(overscaledZ, childTileID);
+                    const OverscaledTileID childDataTileID(overscaledZ, idealRenderTileID.wrap, childTileID);
                     tile = getTile(childDataTileID);
                     if (tile && tile->isRenderable()) {
                         retainTile(*tile, Resource::Necessity::Optional);
-                        renderTile(childDataTileID.unwrapTo(idealRenderTileID.wrap), *tile);
+                        renderTile(childDataTileID.toUnwrapped(), *tile);
                     } else {
                         // At least one child tile doesn't exist, so we are going to look for
                         // parents as well.
@@ -81,8 +81,7 @@ void updateRenderables(GetTileFn getTile,
                 // We couldn't find child tiles that entirely cover the ideal tile.
                 for (overscaledZ = dataTileZoom - 1; overscaledZ >= zoomRange.min; --overscaledZ) {
                     const auto parentDataTileID = idealDataTileID.scaledTo(overscaledZ);
-                    const auto parentRenderTileID =
-                        parentDataTileID.unwrapTo(idealRenderTileID.wrap);
+                    const auto parentRenderTileID = parentDataTileID.toUnwrapped();
 
                     if (checked.find(parentRenderTileID) != checked.end()) {
                         // Break parent tile ascent, this route has been checked by another child
diff --git a/src/mbgl/renderer/tile_pyramid.cpp b/src/mbgl/renderer/tile_pyramid.cpp
index 57e7f6d375..5b1e621743 100644
--- a/src/mbgl/renderer/tile_pyramid.cpp
+++ b/src/mbgl/renderer/tile_pyramid.cpp
@@ -176,15 +176,12 @@ void TilePyramid::update(const std::vector<Immutable<style::Layer::Impl>>& layer
     removeStaleTiles(retain);
 
     for (auto& pair : tiles) {
-        // TODO: Calculating yStretch based on tile distance means we can no longer use the same collision tile for two wrapped
-        // copies of the same data tile. For now the assumption that we're always at "wrap = 0" means collision detection is broken
-        // for wrapped tiles.
         const PlacementConfig config { parameters.transformState.getAngle(),
                                        parameters.transformState.getPitch(),
                                        parameters.transformState.getCameraToCenterDistance(),
-                                       parameters.transformState.getCameraToTileDistance(pair.first.unwrapTo(0)),
+                                       parameters.transformState.getCameraToTileDistance(pair.first.toUnwrapped()),
                                        parameters.debugOptions & MapDebugOptions::Collision };
-        
+
         pair.second->setPlacementConfig(config);
     }
 }
diff --git a/src/mbgl/tile/tile_id.hpp b/src/mbgl/tile/tile_id.hpp
index 1ce3eea98e..811158e9b9 100644
--- a/src/mbgl/tile/tile_id.hpp
+++ b/src/mbgl/tile/tile_id.hpp
@@ -46,8 +46,8 @@ std::string toString(const CanonicalTileID&);
 // z/x/y describe the
 class OverscaledTileID {
 public:
-    OverscaledTileID(uint8_t overscaledZ, CanonicalTileID);
-    OverscaledTileID(uint8_t overscaledZ, uint8_t z, uint32_t x, uint32_t y);
+    OverscaledTileID(uint8_t overscaledZ, int16_t wrap, CanonicalTileID);
+    OverscaledTileID(uint8_t overscaledZ, int16_t wrap, uint8_t z, uint32_t x, uint32_t y);
     OverscaledTileID(uint8_t z, uint32_t x, uint32_t y);
     explicit OverscaledTileID(const CanonicalTileID&);
     explicit OverscaledTileID(CanonicalTileID&&);
@@ -57,9 +57,10 @@ public:
     bool isChildOf(const OverscaledTileID&) const;
     uint32_t overscaleFactor() const;
     OverscaledTileID scaledTo(uint8_t z) const;
-    UnwrappedTileID unwrapTo(int16_t wrap) const;
+    UnwrappedTileID toUnwrapped() const;
 
     const uint8_t overscaledZ;
+    const int16_t wrap;
     const CanonicalTileID canonical;
 };
 
@@ -137,40 +138,40 @@ inline std::array<CanonicalTileID, 4> CanonicalTileID::children() const {
     } };
 }
 
-inline OverscaledTileID::OverscaledTileID(uint8_t overscaledZ_, CanonicalTileID canonical_)
-    : overscaledZ(overscaledZ_), canonical(std::move(canonical_)) {
+inline OverscaledTileID::OverscaledTileID(uint8_t overscaledZ_, int16_t wrap_, CanonicalTileID canonical_)
+    : overscaledZ(overscaledZ_), wrap(wrap_), canonical(std::move(canonical_)) {
     assert(overscaledZ >= canonical.z);
 }
 
-inline OverscaledTileID::OverscaledTileID(uint8_t overscaledZ_, uint8_t z, uint32_t x, uint32_t y)
-    : overscaledZ(overscaledZ_), canonical(z, x, y) {
+inline OverscaledTileID::OverscaledTileID(uint8_t overscaledZ_, int16_t wrap_, uint8_t z, uint32_t x, uint32_t y)
+    : overscaledZ(overscaledZ_), wrap(wrap_), canonical(z, x, y) {
     assert(overscaledZ >= canonical.z);
 }
 
 inline OverscaledTileID::OverscaledTileID(uint8_t z, uint32_t x, uint32_t y)
-    : overscaledZ(z), canonical(z, x, y) {
+    : overscaledZ(z), wrap(0), canonical(z, x, y) {
 }
 
 inline OverscaledTileID::OverscaledTileID(const CanonicalTileID& canonical_)
-    : overscaledZ(canonical_.z), canonical(canonical_) {
+    : overscaledZ(canonical_.z), wrap(0), canonical(canonical_) {
     assert(overscaledZ >= canonical.z);
 }
 
 inline OverscaledTileID::OverscaledTileID(CanonicalTileID&& canonical_)
-    : overscaledZ(canonical_.z), canonical(std::forward<CanonicalTileID>(canonical_)) {
+    : overscaledZ(canonical_.z), wrap(0), canonical(std::forward<CanonicalTileID>(canonical_)) {
     assert(overscaledZ >= canonical.z);
 }
 
 inline bool OverscaledTileID::operator==(const OverscaledTileID& rhs) const {
-    return overscaledZ == rhs.overscaledZ && canonical == rhs.canonical;
+    return overscaledZ == rhs.overscaledZ && wrap == rhs.wrap &&canonical == rhs.canonical;
 }
 
 inline bool OverscaledTileID::operator!=(const OverscaledTileID& rhs) const {
-    return overscaledZ != rhs.overscaledZ || canonical != rhs.canonical;
+    return overscaledZ != rhs.overscaledZ || wrap != rhs.wrap || canonical != rhs.canonical;
 }
 
 inline bool OverscaledTileID::operator<(const OverscaledTileID& rhs) const {
-    return std::tie(overscaledZ, canonical) < std::tie(rhs.overscaledZ, rhs.canonical);
+    return std::tie(overscaledZ, wrap, canonical) < std::tie(rhs.overscaledZ, rhs.wrap, rhs.canonical);
 }
 
 inline uint32_t OverscaledTileID::overscaleFactor() const {
@@ -183,10 +184,10 @@ inline bool OverscaledTileID::isChildOf(const OverscaledTileID& rhs) const {
 }
 
 inline OverscaledTileID OverscaledTileID::scaledTo(uint8_t z) const {
-    return { z, z >= canonical.z ? canonical : canonical.scaledTo(z) };
+    return { z, wrap, z >= canonical.z ? canonical : canonical.scaledTo(z) };
 }
 
-inline UnwrappedTileID OverscaledTileID::unwrapTo(int16_t wrap) const {
+inline UnwrappedTileID OverscaledTileID::toUnwrapped() const {
     return { wrap, canonical };
 }
 
@@ -232,7 +233,7 @@ inline std::array<UnwrappedTileID, 4> UnwrappedTileID::children() const {
 
 inline OverscaledTileID UnwrappedTileID::overscaleTo(const uint8_t overscaledZ) const {
     assert(overscaledZ >= canonical.z);
-    return { overscaledZ, canonical };
+    return { overscaledZ, wrap, canonical };
 }
 
 inline float UnwrappedTileID::pixelsToTileUnits(const float pixelValue, const float zoom) const {
diff --git a/test/algorithm/update_renderables.test.cpp b/test/algorithm/update_renderables.test.cpp
index af90d262de..26b7cf7f72 100644
--- a/test/algorithm/update_renderables.test.cpp
+++ b/test/algorithm/update_renderables.test.cpp
@@ -23,10 +23,10 @@ struct GetTileDataAction {
 };
 
 std::ostream& operator<<(std::ostream& os, const GetTileDataAction& action) {
-    return os << "GetTileDataAction{ { " << int(action.tileID.overscaledZ) << ", { "
+    return os << "GetTileDataAction{ { " << int(action.tileID.overscaledZ) << ", " << int(action.tileID.wrap) << ", { "
               << int(action.tileID.canonical.z) << ", " << action.tileID.canonical.x << ", "
               << action.tileID.canonical.y << " } }, "
-              << (action.found == Found ? "Found" : "NotFound") << " }";
+              << (action.found == Found ? "Found" : "NotFound") << " }\n";
 }
 
 struct CreateTileDataAction {
@@ -38,9 +38,9 @@ struct CreateTileDataAction {
 };
 
 std::ostream& operator<<(std::ostream& os, const CreateTileDataAction& action) {
-    return os << "CreateTileDataAction{ { " << int(action.tileID.overscaledZ) << ", { "
+    return os << "CreateTileDataAction{ { " << int(action.tileID.overscaledZ) << ", " << int(action.tileID.wrap) << ", { "
               << int(action.tileID.canonical.z) << ", " << action.tileID.canonical.x << ", "
-              << action.tileID.canonical.y << " } } }";
+              << action.tileID.canonical.y << " } } }\n";
 }
 
 struct RetainTileDataAction {
@@ -53,10 +53,10 @@ struct RetainTileDataAction {
 };
 
 std::ostream& operator<<(std::ostream& os, const RetainTileDataAction& action) {
-    return os << "RetainTileDataAction{ { " << int(action.tileID.overscaledZ) << ", { "
+    return os << "RetainTileDataAction{ { " << int(action.tileID.overscaledZ) << ", " << int(action.tileID.wrap) << ", { "
               << int(action.tileID.canonical.z) << ", " << action.tileID.canonical.x << ", "
               << action.tileID.canonical.y << " } }, "
-              << (action.necessity == Resource::Necessity::Required ? "Required" : "Optional") << " }";
+              << (action.necessity == Resource::Necessity::Required ? "Required" : "Optional") << " }\n";
 }
 
 struct RenderTileAction {
@@ -76,7 +76,7 @@ std::ostream& operator<<(std::ostream& os, const RenderTileAction& action) {
               << int(action.tileData.tileID.overscaledZ) << "_"
               << int(action.tileData.tileID.canonical.z) << "_"
               << action.tileData.tileID.canonical.x << "_" << action.tileData.tileID.canonical.y
-              << " }";
+              << " }\n";
 }
 
 using ActionLogEntry =
@@ -129,8 +129,8 @@ TEST(UpdateRenderables, SingleTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, Found },       // found ideal tile
-                  RetainTileDataAction{ { 1, { 1, 1, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, Found },       // found ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 1, 1 }, *tile_1_1_1_1 },       // render ideal tile
               }),
               log);
@@ -140,8 +140,8 @@ TEST(UpdateRenderables, SingleTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, Found },       // found ideal tile
-                  RetainTileDataAction{ { 1, { 1, 1, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, Found },       // found ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 1, 1 }, *tile_1_1_1_1 },       // render ideal tile
               }),
               log);
@@ -152,39 +152,39 @@ TEST(UpdateRenderables, SingleTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, NotFound },    // missing ideal tile
-                  CreateTileDataAction{ { 1, { 1, 0, 1 } } },           // create ideal tile
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 2 } }, NotFound },    // four child tiles
-                  GetTileDataAction{ { 2, { 2, 0, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 2 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // parent tile
-
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, Found },       // found ideal tile
-                  RetainTileDataAction{ { 1, { 1, 1, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, NotFound },    // missing ideal tile
+                  CreateTileDataAction{ { 1, 0, { 1, 0, 1 } } },           // create ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 2 } }, NotFound },    // four child tiles
+                  GetTileDataAction{ { 2, 0, { 2, 0, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 2 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // parent tile
+
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, Found },       // found ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 1, 1 }, *tile_1_1_1_1 },       // render found tile
               }),
               log);
 
     // Mark the created tile as having the optional request tried.
     log.clear();
-    source.dataTiles[{ 1, { 1, 0, 1 } }]->triedOptional = true;
+    source.dataTiles[{ 1, 0, { 1, 0, 1 } }]->triedOptional = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, Found },       // missing ideal tile
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 2 } }, NotFound },    // four child tiles
-                  GetTileDataAction{ { 2, { 2, 0, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 2 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // parent tile
-                  CreateTileDataAction{ { 0, { 0, 0, 0 } } },           // load parent tile
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
-
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, Found },       // found ideal tile
-                  RetainTileDataAction{ { 1, { 1, 1, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, Found },       // missing ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 2 } }, NotFound },    // four child tiles
+                  GetTileDataAction{ { 2, 0, { 2, 0, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 2 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // parent tile
+                  CreateTileDataAction{ { 0, 0, { 0, 0, 0 } } },           // load parent tile
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, Found },       // found ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 1, 1 }, *tile_1_1_1_1 },       // render found tile
               }),
               log);
@@ -196,12 +196,12 @@ TEST(UpdateRenderables, SingleTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, Found },       // newly added tile
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, Found },       // newly added tile
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 0, 1 }, *tile_1_1_0_1 },       // render ideal tile
 
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, Found },       // ideal tile
-                  RetainTileDataAction{ { 1, { 1, 1, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, Found },       // ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 1, 1 }, *tile_1_1_1_1 },       // render found tile
               }),
               log);
@@ -215,22 +215,22 @@ TEST(UpdateRenderables, SingleTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       // found tile, not ready
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // four child tiles
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent tile
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found },       // found tile, not ready
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // four child tiles
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent tile
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   // optional parent tile was already created before, but is not renderable
 
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, Found },       // ideal tile
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, Found },       // ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 0, 1 }, *tile_1_1_0_1 },       // render ideal tile
 
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, Found },       // ideal tile
-                  RetainTileDataAction{ { 1, { 1, 1, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, Found },       // ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 1, 1 }, *tile_1_1_1_1 },       // render ideal tile
               }),
               log);
@@ -241,16 +241,16 @@ TEST(UpdateRenderables, SingleTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       // found tile, now ready
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found },       // found tile, now ready
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 0, 0 }, *tile_1_1_0_0 },       //
 
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, Found },       // ideal tile
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, Found },       // ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 0, 1 }, *tile_1_1_0_1 },       //
 
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, Found },       // ideal tile
-                  RetainTileDataAction{ { 1, { 1, 1, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, Found },       // ideal tile
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 1, 1 }, *tile_1_1_1_1 },       //
               }),
               log);
@@ -274,30 +274,30 @@ TEST(UpdateRenderables, UseParentTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, NotFound },    // missing ideal tile
-                  CreateTileDataAction{ { 1, { 1, 0, 1 } } },           //
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 2 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 2, { 2, 0, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 2 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent found!
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, NotFound },    // missing ideal tile
+                  CreateTileDataAction{ { 1, 0, { 1, 0, 1 } } },           //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 2 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 2, 0, { 2, 0, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 2 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent found!
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       // render parent
-                  GetTileDataAction{ { 1, { 1, 1, 0 } }, NotFound },    // missing ideal tile
-                  CreateTileDataAction{ { 1, { 1, 1, 0 } } },           //
-                  RetainTileDataAction{ { 1, { 1, 1, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 2, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 2, { 2, 2, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 3, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 3, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, NotFound },    // missing tile
-                  CreateTileDataAction{ { 1, { 1, 1, 1 } } },           //
-                  RetainTileDataAction{ { 1, { 1, 1, 1 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 2, 2 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 2, { 2, 2, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 3, 2 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 3, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 1, 0 } }, NotFound },    // missing ideal tile
+                  CreateTileDataAction{ { 1, 0, { 1, 1, 0 } } },           //
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 2, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 2, 0, { 2, 2, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 3, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 3, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, NotFound },    // missing tile
+                  CreateTileDataAction{ { 1, 0, { 1, 1, 1 } } },           //
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 2, 2 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 2, 0, { 2, 2, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 3, 2 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 3, 3 } }, NotFound },    // ...
               }),
               log);
 }
@@ -317,34 +317,34 @@ TEST(UpdateRenderables, DontUseWrongParentTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // missing ideal tile
-                  CreateTileDataAction{ { 2, { 2, 0, 0 } } },           //
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 3, { 3, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // parent tile, missing
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // parent tile, missing
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // missing ideal tile
+                  CreateTileDataAction{ { 2, 0, { 2, 0, 0 } } },           //
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 3, 0, { 3, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // parent tile, missing
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // parent tile, missing
               }),
               log);
 
     // Now mark the created tile as having the optional request tried.
     log.clear();
-    source.dataTiles[{ 2, { 2, 0, 0 } }]->triedOptional = true;
+    source.dataTiles[{ 2, 0, { 2, 0, 0 } }]->triedOptional = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // non-ready ideal tile
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 3, { 3, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // parent tile, missing
-                  CreateTileDataAction{ { 1, { 1, 0, 0 } } },           // find optional parent
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // parent tile, missing
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // non-ready ideal tile
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 3, 0, { 3, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // parent tile, missing
+                  CreateTileDataAction{ { 1, 0, { 1, 0, 0 } } },           // find optional parent
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // parent tile, missing
               }),
               log);
 
@@ -354,26 +354,26 @@ TEST(UpdateRenderables, DontUseWrongParentTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // non-ready ideal tile
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // non-ready ideal tile
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
                   // this tile was added by the previous invocation of updateRenderables
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 3, { 3, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       // parent tile not ready
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // missing parent tile
-
-                  GetTileDataAction{ { 2, { 2, 2, 0 } }, NotFound },    // missing ideal tile
-                  CreateTileDataAction{ { 2, { 2, 2, 0 } } },           //
-                  RetainTileDataAction{ { 2, { 2, 2, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 3, { 3, 4, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 3, { 3, 4, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 5, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 5, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 1, 0 } }, Found },       // found parent tile
-                  RetainTileDataAction{ { 1, { 1, 1, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 3, 0, { 3, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found },       // parent tile not ready
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // missing parent tile
+
+                  GetTileDataAction{ { 2, 0, { 2, 2, 0 } }, NotFound },    // missing ideal tile
+                  CreateTileDataAction{ { 2, 0, { 2, 2, 0 } } },           //
+                  RetainTileDataAction{ { 2, 0, { 2, 2, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 3, 0, { 3, 4, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 3, 0, { 3, 4, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 5, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 5, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 1, 0 } }, Found },       // found parent tile
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 1, 1, 0 }, *tile_1_1_1_0 },       // render parent tile
               }),
               log);
@@ -399,14 +399,14 @@ TEST(UpdateRenderables, UseParentTileWhenChildNotReady) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, Found },       // found, but not ready
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 2 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 2, { 2, 0, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 2 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 3 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent tile, ready
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, Found },       // found, but not ready
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 2 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 2, 0, { 2, 0, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 2 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 3 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent tile, ready
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       // render parent tile
               }),
               log);
@@ -417,8 +417,8 @@ TEST(UpdateRenderables, UseParentTileWhenChildNotReady) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, Found },       // found and ready
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, Found },       // found and ready
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 0, 1 }, *tile_1_1_0_1 },       // render ideal tile
               }),
               log);
@@ -444,19 +444,19 @@ TEST(UpdateRenderables, UseOverlappingParentTile) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ideal tile not found
-                  CreateTileDataAction{ { 1, { 1, 0, 0 } } },           //
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent tile found
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ideal tile not found
+                  CreateTileDataAction{ { 1, 0, { 1, 0, 0 } } },           //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent tile found
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       //
 
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, Found },       // ideal tile found
-                  RetainTileDataAction{ { 1, { 1, 0, 1 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, Found },       // ideal tile found
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 1 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 1, 0, 1 }, *tile_1_1_0_1 },       //
               }),
               log);
@@ -480,17 +480,17 @@ TEST(UpdateRenderables, UseChildTiles) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 0);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ideal tile, missing
-                  CreateTileDataAction{ { 0, { 0, 0, 0 } } },           //
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       // child tile found
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ideal tile, missing
+                  CreateTileDataAction{ { 0, 0, { 0, 0, 0 } } },           //
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found },       // child tile found
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 1, 0, 0 }, *tile_1_1_0_0 },       // render child tile
-                  GetTileDataAction{ { 1, { 1, 0, 1 } }, NotFound },    // child tile not found
-                  GetTileDataAction{ { 1, { 1, 1, 0 } }, Found },       // child tile found
-                  RetainTileDataAction{ { 1, { 1, 1, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 1 } }, NotFound },    // child tile not found
+                  GetTileDataAction{ { 1, 0, { 1, 1, 0 } }, Found },       // child tile found
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 1, 1, 0 }, *tile_1_1_1_0 },       // render child tile
-                  GetTileDataAction{ { 1, { 1, 1, 1 } }, NotFound },    // child tile not found
+                  GetTileDataAction{ { 1, 0, { 1, 1, 1 } }, NotFound },    // child tile not found
                   // no parent tile of 0 to consider
               }),
               log);
@@ -514,17 +514,17 @@ TEST(UpdateRenderables, PreferChildTiles) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ideal tile, not found
-                  CreateTileDataAction{ { 1, { 1, 0, 0 } } },           //
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // child tile, found
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ideal tile, not found
+                  CreateTileDataAction{ { 1, 0, { 1, 0, 0 } } },           //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // child tile, found
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_2_2_0_0 },       //
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, NotFound },    // child tile, not found
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent tile, found
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, NotFound },    // child tile, not found
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent tile, found
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       //
               }),
               log);
@@ -537,19 +537,19 @@ TEST(UpdateRenderables, PreferChildTiles) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found }, // ideal tile, not ready
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found }, // ideal tile, not ready
                   // ideal tile was added in previous invocation, but is not yet ready
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // child tile, found
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // child tile, found
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_2_2_0_0 },       //
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, Found },       // ...
-                  RetainTileDataAction{ { 2, { 2, 0, 1 } }, Resource::Necessity::Optional }, // ...
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, Found },       // ...
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 1 } }, Resource::Necessity::Optional }, // ...
                   RenderTileAction{ { 2, 0, 1 }, *tile_2_2_0_1 },       //
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, NotFound },    // child tile, not found
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent tile, found
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, NotFound },    // child tile, not found
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent tile, found
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       //
               }),
               log);
@@ -560,21 +560,21 @@ TEST(UpdateRenderables, PreferChildTiles) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found }, // ideal tile, not ready
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found }, // ideal tile, not ready
                   // ideal tile was added in first invocation, but is not yet ready
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // child tile, found
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // child tile, found
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_2_2_0_0 },       //
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, Found },       // ...
-                  RetainTileDataAction{ { 2, { 2, 0, 1 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, Found },       // ...
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 1 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 1 }, *tile_2_2_0_1 },       //
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, Found },       // ...
-                  RetainTileDataAction{ { 2, { 2, 1, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, Found },       // ...
+                  RetainTileDataAction{ { 2, 0, { 2, 1, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 1, 0 }, *tile_2_2_1_0 },       //
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    // child tile, not found
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent tile, found
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, NotFound },    // child tile, not found
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent tile, found
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       //
               }),
               log);
@@ -586,20 +586,20 @@ TEST(UpdateRenderables, PreferChildTiles) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found }, // ideal tile, not ready
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found }, // ideal tile, not ready
                   // ideal tile was added in first invocation, but is not yet ready
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // child tile, found
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // child tile, found
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_2_2_0_0 },       //
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, Found },       // ...
-                  RetainTileDataAction{ { 2, { 2, 0, 1 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, Found },       // ...
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 1 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 1 }, *tile_2_2_0_1 },       //
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, Found },       // ...
-                  RetainTileDataAction{ { 2, { 2, 1, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, Found },       // ...
+                  RetainTileDataAction{ { 2, 0, { 2, 1, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 1, 0 }, *tile_2_2_1_0 },       //
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, Found },       // ...
-                  RetainTileDataAction{ { 2, { 2, 1, 1 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, Found },       // ...
+                  RetainTileDataAction{ { 2, 0, { 2, 1, 1 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 1, 1 }, *tile_2_2_1_1 },       //
               }),
               log);
@@ -624,17 +624,17 @@ TEST(UpdateRenderables, UseParentAndChildTiles) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ideal tile, missing
-                  CreateTileDataAction{ { 1, { 1, 0, 0 } } },           //
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // child tile
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ideal tile, missing
+                  CreateTileDataAction{ { 1, 0, { 1, 0, 0 } } },           //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // child tile
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_2_2_0_0 },       //
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent tile
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent tile
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       //
               }),
               log);
@@ -645,14 +645,14 @@ TEST(UpdateRenderables, UseParentAndChildTiles) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       // parent tile
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       // parent tile
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       //
               }),
               log);
@@ -675,13 +675,13 @@ TEST(UpdateRenderables, DontUseTilesLowerThanMinzoom) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ideal tile, missing
-                  CreateTileDataAction{ { 2, { 2, 0, 0 } } },           //
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 3, { 3, 0, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 3, { 3, 1, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 3, { 3, 1, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ideal tile, missing
+                  CreateTileDataAction{ { 2, 0, { 2, 0, 0 } } },           //
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 3, 0, { 3, 1, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 3, 0, { 3, 1, 1 } }, NotFound },    //
                   // no requests for zoom 1 tiles
               }),
               log);
@@ -705,58 +705,58 @@ TEST(UpdateRenderables, UseOverzoomedTileAfterMaxzoom) {
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(
         ActionLog({
-            GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ideal tile, missing
-            CreateTileDataAction{ { 2, { 2, 0, 0 } } },           //
-            RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-            GetTileDataAction{ { 3, { 2, 0, 0 } }, NotFound },    // overzoomed tile, not children!
-            GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    //
-            GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    //
+            GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ideal tile, missing
+            CreateTileDataAction{ { 2, 0, { 2, 0, 0 } } },           //
+            RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+            GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, NotFound },    // overzoomed tile, not children!
+            GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    //
+            GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    //
         }),
         log);
 
     // Mark the created tile as having tried the optional request.
     log.clear();
-    source.dataTiles[{ 2, { 2, 0, 0 } }]->triedOptional = true;
+    source.dataTiles[{ 2, 0, { 2, 0, 0 } }]->triedOptional = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(
         ActionLog({
-            GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // ideal tile, missing
-            RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-            GetTileDataAction{ { 3, { 2, 0, 0 } }, NotFound },    // overzoomed tile, not children!
-            GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    //
-            CreateTileDataAction{ { 1, { 1, 0, 0 } } },           //
-            RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
-            GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    //
+            GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // ideal tile, missing
+            RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+            GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, NotFound },    // overzoomed tile, not children!
+            GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    //
+            CreateTileDataAction{ { 1, 0, { 1, 0, 0 } } },           //
+            RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
+            GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    //
         }),
         log);
 
     // Only add a non-overzoomed ("parent") tile at first.
     log.clear();
-    auto tile_2_2_0_0 = source.createTileData(OverscaledTileID{ 2, { 2, 0, 0 } });
+    auto tile_2_2_0_0 = source.createTileData(OverscaledTileID{ 2, 0, { 2, 0, 0 } });
     tile_2_2_0_0->renderable = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 3);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 3, { 2, 0, 0 } }, NotFound },    // ideal tile, missing
-                  CreateTileDataAction{ { 3, { 2, 0, 0 } } },           //
-                  RetainTileDataAction{ { 3, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 4, { 2, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, NotFound },    // ideal tile, missing
+                  CreateTileDataAction{ { 3, 0, { 2, 0, 0 } } },           //
+                  RetainTileDataAction{ { 3, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 4, 0, { 2, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       //
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_2_2_0_0 },       //
               }),
               log);
 
     // Then add the overzoomed tile matching the zoom level we're rendering.
     log.clear();
-    auto tile_3_2_0_0 = source.createTileData(OverscaledTileID{ 3, { 2, 0, 0 } });
+    auto tile_3_2_0_0 = source.createTileData(OverscaledTileID{ 3, 0, { 2, 0, 0 } });
     tile_3_2_0_0->renderable = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 3);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 3, { 2, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 3, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, Found },       //
+                  RetainTileDataAction{ { 3, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_3_2_0_0 },       //
               }),
               log);
@@ -766,26 +766,26 @@ TEST(UpdateRenderables, UseOverzoomedTileAfterMaxzoom) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       //
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_2_2_0_0 },       //
               }),
               log);
 
     // Now remove the best match.
     log.clear();
-    source.dataTiles.erase(OverscaledTileID{ 2, { 2, 0, 0 } });
+    source.dataTiles.erase(OverscaledTileID{ 2, 0, { 2, 0, 0 } });
     tile_2_2_0_0 = nullptr;
 
     // Use the overzoomed tile even though it doesn't match the zoom level.
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    //
-                  CreateTileDataAction{ { 2, { 2, 0, 0 } } },           //
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 3, { 2, 0, 0 } }, Found },       // use overzoomed tile!
-                  RetainTileDataAction{ { 3, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    //
+                  CreateTileDataAction{ { 2, 0, { 2, 0, 0 } } },           //
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, Found },       // use overzoomed tile!
+                  RetainTileDataAction{ { 3, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_3_2_0_0 },       //
               }),
               log);
@@ -803,69 +803,69 @@ TEST(UpdateRenderables, AscendToNonOverzoomedTiles) {
     source.idealTiles.emplace(UnwrappedTileID{ 2, 0, 0 });
 
     // Add a matching overzoomed tile and make sure it gets selected.
-    auto tile_3_2_0_0 = source.createTileData(OverscaledTileID{ 3, { 2, 0, 0 } });
+    auto tile_3_2_0_0 = source.createTileData(OverscaledTileID{ 3, 0, { 2, 0, 0 } });
     tile_3_2_0_0->renderable = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 3);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 3, { 2, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 3, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, Found },       //
+                  RetainTileDataAction{ { 3, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_3_2_0_0 },       //
               }),
               log);
 
     // Then, swap it with a non-overzoomed tile.
     log.clear();
-    source.dataTiles.erase(OverscaledTileID{ 3, { 2, 0, 0 } });
+    source.dataTiles.erase(OverscaledTileID{ 3, 0, { 2, 0, 0 } });
     tile_3_2_0_0 = nullptr;
-    auto tile_2_2_0_0 = source.createTileData(OverscaledTileID{ 2, { 2, 0, 0 } });
+    auto tile_2_2_0_0 = source.createTileData(OverscaledTileID{ 2, 0, { 2, 0, 0 } });
     tile_2_2_0_0->renderable = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 3);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 3, { 2, 0, 0 } }, NotFound },    //
-                  CreateTileDataAction{ { 3, { 2, 0, 0 } } },           //
-                  RetainTileDataAction{ { 3, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 4, { 2, 0, 0 } }, NotFound }, // prefer using a child first
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },    //
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, NotFound },    //
+                  CreateTileDataAction{ { 3, 0, { 2, 0, 0 } } },           //
+                  RetainTileDataAction{ { 3, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 4, 0, { 2, 0, 0 } }, NotFound }, // prefer using a child first
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },    //
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 2, 0, 0 }, *tile_2_2_0_0 },       //
               }),
               log);
 
     // Then, swap it with a parent tile.
     log.clear();
-    source.dataTiles.erase(OverscaledTileID{ 2, { 2, 0, 0 } });
+    source.dataTiles.erase(OverscaledTileID{ 2, 0, { 2, 0, 0 } });
     tile_2_2_0_0 = nullptr;
-    auto tile_1_1_0_0 = source.createTileData(OverscaledTileID{ 1, { 1, 0, 0 } });
+    auto tile_1_1_0_0 = source.createTileData(OverscaledTileID{ 1, 0, { 1, 0, 0 } });
     tile_1_1_0_0->renderable = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 3);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 3, { 2, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 3, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 4, { 2, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 3, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 4, 0, { 2, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found },       //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 1, 0, 0 }, *tile_1_1_0_0 },       //
               }),
               log);
 
     // Now, mark the created tile as found.
     log.clear();
-    source.dataTiles[{ 3, { 2, 0, 0 } }]->triedOptional = true;
+    source.dataTiles[{ 3, 0, { 2, 0, 0 } }]->triedOptional = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 3);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 3, { 2, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 3, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 4, { 2, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    //
-                  CreateTileDataAction{ { 2, { 2, 0, 0 } } },           //
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 2, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 3, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 4, 0, { 2, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    //
+                  CreateTileDataAction{ { 2, 0, { 2, 0, 0 } } },           //
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found },       //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 1, 0, 0 }, *tile_1_1_0_0 },       //
               }),
               log);
@@ -885,60 +885,60 @@ TEST(UpdateRenderables, DoNotAscendMultipleTimesIfNotFound) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 8);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 8, { 8, 0, 0 } }, NotFound },    // ideal tile
-                  CreateTileDataAction{ { 8, { 8, 0, 0 } } },           //
-                  RetainTileDataAction{ { 8, { 8, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 9, { 9, 0, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 9, { 9, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 9, { 9, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 9, { 9, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // ascent
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ...
-
-                  GetTileDataAction{ { 8, { 8, 1, 0 } }, NotFound },    // ideal tile
-                  CreateTileDataAction{ { 8, { 8, 1, 0 } } },           //
-                  RetainTileDataAction{ { 8, { 8, 1, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 9, { 9, 2, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 9, { 9, 2, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 9, { 9, 3, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 9, { 9, 3, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 8, 0, { 8, 0, 0 } }, NotFound },    // ideal tile
+                  CreateTileDataAction{ { 8, 0, { 8, 0, 0 } } },           //
+                  RetainTileDataAction{ { 8, 0, { 8, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 9, 0, { 9, 0, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 9, 0, { 9, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 9, 0, { 9, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 9, 0, { 9, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // ascent
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ...
+
+                  GetTileDataAction{ { 8, 0, { 8, 1, 0 } }, NotFound },    // ideal tile
+                  CreateTileDataAction{ { 8, 0, { 8, 1, 0 } } },           //
+                  RetainTileDataAction{ { 8, 0, { 8, 1, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 9, 0, { 9, 2, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 9, 0, { 9, 2, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 9, 0, { 9, 3, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 9, 0, { 9, 3, 1 } }, NotFound },    // ...
                   // no second ascent to 0
               }),
               log);
 
     // Now add a mid-level tile that stops the ascent
     log.clear();
-    auto tile_4_0_0_0 = source.createTileData(OverscaledTileID{ 4, { 4, 0, 0 } });
+    auto tile_4_0_0_0 = source.createTileData(OverscaledTileID{ 4, 0, { 4, 0, 0 } });
     tile_4_0_0_0->renderable = true;
 
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 8);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 8, { 8, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 8, { 8, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 9, { 9, 0, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 9, { 9, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 9, { 9, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 9, { 9, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // ascent
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, Found },       // stops ascent
-                  RetainTileDataAction{ { 4, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 8, 0, { 8, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 8, 0, { 8, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 9, 0, { 9, 0, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 9, 0, { 9, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 9, 0, { 9, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 9, 0, { 9, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // ascent
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, Found },       // stops ascent
+                  RetainTileDataAction{ { 4, 0, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 4, 0, 0 }, *tile_4_0_0_0 },       //
 
-                  GetTileDataAction{ { 8, { 8, 1, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 8, { 8, 1, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 9, { 9, 2, 0 } }, NotFound },    // child tile
-                  GetTileDataAction{ { 9, { 9, 2, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 9, { 9, 3, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 9, { 9, 3, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 8, 0, { 8, 1, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 8, 0, { 8, 1, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 9, 0, { 9, 2, 0 } }, NotFound },    // child tile
+                  GetTileDataAction{ { 9, 0, { 9, 2, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 9, 0, { 9, 3, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 9, 0, { 9, 3, 1 } }, NotFound },    // ...
                   // no second ascent to 0
               }),
               log);
@@ -960,15 +960,15 @@ TEST(UpdateRenderables, DontRetainUnusedNonIdealTiles) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 2);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 3, { 3, 0, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 3, { 3, 1, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 3, { 3, 1, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       // parent tile, not ready
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 3, 0, { 3, 1, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 3, 0, { 3, 1, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, Found },       // parent tile, not ready
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    //
               }),
               log);
 }
@@ -981,56 +981,54 @@ TEST(UpdateRenderables, WrappedTiles) {
     auto retainTileData = retainTileDataFn(log);
     auto renderTile = renderTileFn(log);
 
-    source.idealTiles.emplace(UnwrappedTileID{ 1, -1, 0 });
-    source.idealTiles.emplace(UnwrappedTileID{ 1, 0, 0 });
-    source.idealTiles.emplace(UnwrappedTileID{ 1, 1, 0 });
-    source.idealTiles.emplace(UnwrappedTileID{ 1, 2, 0 });
+    source.idealTiles.emplace(UnwrappedTileID{ 1, -1, 0 }); // 'wrap' -> -1
+    source.idealTiles.emplace(UnwrappedTileID{ 1, 0, 0 });  // 'wrap' -> 0
+    source.idealTiles.emplace(UnwrappedTileID{ 1, 1, 0 });  // 'wrap' -> 0
+    source.idealTiles.emplace(UnwrappedTileID{ 1, 2, 0 });  // 'wrap' -> 1
 
-    auto tile_0_0_0_0 = source.createTileData(OverscaledTileID{ 0, { 0, 0, 0 } });
+    auto tile_0_0_0_0 = source.createTileData(OverscaledTileID{ 0, 0, { 0, 0, 0 } });
     tile_0_0_0_0->renderable = true;
 
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 1);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 1, { 1, 1, 0 } }, NotFound },    // ideal tile 1/-1/0
-                  CreateTileDataAction{ { 1, { 1, 1, 0 } } },           //
-                  RetainTileDataAction{ { 1, { 1, 1, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 2, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 2, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 3, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 3, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
-                  RenderTileAction{ { 0, -1, 0 }, *tile_0_0_0_0 },      //
-
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ideal tile 1/0/0
-                  CreateTileDataAction{ { 1, { 1, 0, 0 } } },           //
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, -1, { 1, 1, 0 } }, NotFound },    // ideal tile 1/-1/0 (wrapped to -1)
+                  CreateTileDataAction{ { 1, -1, { 1, 1, 0 } } },           //
+                  RetainTileDataAction{ { 1, -1, { 1, 1, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, -1, { 2, 2, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, -1, { 2, 2, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 2, -1, { 2, 3, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, -1, { 2, 3, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 0, -1, { 0, 0, 0 } }, NotFound },    // { 0, 0, 0 } exists, but not the version wrapped to -1
+
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ideal tile 1/0/0
+                  CreateTileDataAction{ { 1, 0, { 1, 0, 0 } } },           //
+                  RetainTileDataAction{ { 1, 0, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 1, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, Found },       //
+                  RetainTileDataAction{ { 0, 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 0, 0, 0 }, *tile_0_0_0_0 },       //
 
-                  GetTileDataAction{ { 1, { 1, 1, 0 } }, Found },       // ideal tile 1/1/0
-                  RetainTileDataAction{ { 1, { 1, 1, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 2, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 2, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 3, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 3, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 1, 0, { 1, 1, 0 } }, NotFound },       // ideal tile 1/1/0, doesn't match 1/-/1/0
+                  CreateTileDataAction{ { 1, 0, { 1, 1, 0 } } },
+                  RetainTileDataAction{ { 1, 0, { 1, 1, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 0, { 2, 2, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 2, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 3, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 0, { 2, 3, 1 } }, NotFound },    //
                   // do not ascent; 0/0/0 has been rendered already for 1/0/0
 
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, Found },       // ideal tile 1/2/0
-                  RetainTileDataAction{ { 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 0, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 1, 0 } }, NotFound },    //
-                  GetTileDataAction{ { 2, { 2, 1, 1 } }, NotFound },    //
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, Found },       //
-                  RetainTileDataAction{ { 0, { 0, 0, 0 } }, Resource::Necessity::Optional }, //
-                  RenderTileAction{ { 0, 1, 0 }, *tile_0_0_0_0 },       //
+                  GetTileDataAction{ { 1, 1, { 1, 0, 0 } }, NotFound },       // ideal tile 1/2/0 (wrapped to 1)
+                  CreateTileDataAction{ { 1, 1, { 1, 0, 0 } } },
+                  RetainTileDataAction{ { 1, 1, { 1, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 2, 1, { 2, 0, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 1, { 2, 0, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 1, { 2, 1, 0 } }, NotFound },    //
+                  GetTileDataAction{ { 2, 1, { 2, 1, 1 } }, NotFound },    //
+                  GetTileDataAction{ { 0, 1, { 0, 0, 0 } }, NotFound },    // { 0, 0, 0 } exists, but not the version wrapped to -1
               }),
               log);
 }
@@ -1048,19 +1046,19 @@ TEST(UpdateRenderables, RepeatedRenderWithMissingOptionals) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, NotFound },    // ideal tile, not found
-                  CreateTileDataAction{ { 6, { 6, 0, 0 } } },           //
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // children
-                  GetTileDataAction{ { 7, { 7, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, NotFound },    // ascent
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, NotFound },    // ideal tile, not found
+                  CreateTileDataAction{ { 6, 0, { 6, 0, 0 } } },           //
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // children
+                  GetTileDataAction{ { 7, 0, { 7, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, NotFound },    // ascent
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ...
               }),
               log);
 
@@ -1069,41 +1067,41 @@ TEST(UpdateRenderables, RepeatedRenderWithMissingOptionals) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // children
-                  GetTileDataAction{ { 7, { 7, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, NotFound },    // ascent
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // children
+                  GetTileDataAction{ { 7, 0, { 7, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, NotFound },    // ascent
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ...
               }),
               log);
 
     // Mark next level has having tried optional.
     log.clear();
-    source.dataTiles[{ 6, { 6, 0, 0 } }]->triedOptional = true;
+    source.dataTiles[{ 6, 0, { 6, 0, 0 } }]->triedOptional = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // children
-                  GetTileDataAction{ { 7, { 7, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, NotFound },    // ascent
-                  CreateTileDataAction{ { 5, { 5, 0, 0 } } },           //
-                  RetainTileDataAction{ { 5, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // children
+                  GetTileDataAction{ { 7, 0, { 7, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, NotFound },    // ascent
+                  CreateTileDataAction{ { 5, 0, { 5, 0, 0 } } },           //
+                  RetainTileDataAction{ { 5, 0, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ...
               }),
               log);
 
@@ -1112,116 +1110,116 @@ TEST(UpdateRenderables, RepeatedRenderWithMissingOptionals) {
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // children
-                  GetTileDataAction{ { 7, { 7, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, Found },       // ascent
-                  RetainTileDataAction{ { 5, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // children
+                  GetTileDataAction{ { 7, 0, { 7, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, Found },       // ascent
+                  RetainTileDataAction{ { 5, 0, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ...
               }),
               log);
 
     // Mark next level has having tried optional.
     log.clear();
-    source.dataTiles[{ 5, { 5, 0, 0 } }]->triedOptional = true;
+    source.dataTiles[{ 5, 0, { 5, 0, 0 } }]->triedOptional = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // children
-                  GetTileDataAction{ { 7, { 7, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, Found },       // ascent
-                  RetainTileDataAction{ { 5, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, NotFound },    // ...
-                  CreateTileDataAction{ { 4, { 4, 0, 0 } } },           //
-                  RetainTileDataAction{ { 4, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // children
+                  GetTileDataAction{ { 7, 0, { 7, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, Found },       // ascent
+                  RetainTileDataAction{ { 5, 0, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, NotFound },    // ...
+                  CreateTileDataAction{ { 4, 0, { 4, 0, 0 } } },           //
+                  RetainTileDataAction{ { 4, 0, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ...
               }),
               log);
 
     // Mark next level has having tried optional.
     log.clear();
-    source.dataTiles[{ 4, { 4, 0, 0 } }]->triedOptional = true;
+    source.dataTiles[{ 4, 0, { 4, 0, 0 } }]->triedOptional = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // children
-                  GetTileDataAction{ { 7, { 7, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, Found },       // ascent
-                  RetainTileDataAction{ { 5, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, Found },       // ...
-                  RetainTileDataAction{ { 4, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound },    // ...
-                  CreateTileDataAction{ { 3, { 3, 0, 0 } } },           //
-                  RetainTileDataAction{ { 3, { 3, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // children
+                  GetTileDataAction{ { 7, 0, { 7, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, Found },       // ascent
+                  RetainTileDataAction{ { 5, 0, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, Found },       // ...
+                  RetainTileDataAction{ { 4, 0, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound },    // ...
+                  CreateTileDataAction{ { 3, 0, { 3, 0, 0 } } },           //
+                  RetainTileDataAction{ { 3, 0, { 3, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ...
               }),
               log);
 
     // Mark next level has having tried optional.
     log.clear();
-    source.dataTiles[{ 3, { 3, 0, 0 } }]->triedOptional = true;
+    source.dataTiles[{ 3, 0, { 3, 0, 0 } }]->triedOptional = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // children
-                  GetTileDataAction{ { 7, { 7, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, Found },       // ascent
-                  RetainTileDataAction{ { 5, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, Found },       // ...
-                  RetainTileDataAction{ { 4, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, Found },       // ...
-                  RetainTileDataAction{ { 3, { 3, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound },    // ...
-                  CreateTileDataAction{ { 2, { 2, 0, 0 } } },           //
-                  RetainTileDataAction{ { 2, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // children
+                  GetTileDataAction{ { 7, 0, { 7, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, Found },       // ascent
+                  RetainTileDataAction{ { 5, 0, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, Found },       // ...
+                  RetainTileDataAction{ { 4, 0, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, Found },       // ...
+                  RetainTileDataAction{ { 3, 0, { 3, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound },    // ...
+                  CreateTileDataAction{ { 2, 0, { 2, 0, 0 } } },           //
+                  RetainTileDataAction{ { 2, 0, { 2, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound },    // ...
               }),
               log);
 
     // Mark as found
     log.clear();
-    auto tile_3_3_0_0 = source.dataTiles[{ 3, { 3, 0, 0 } }].get();
+    auto tile_3_3_0_0 = source.dataTiles[{ 3, 0, { 3, 0, 0 } }].get();
     tile_3_3_0_0->renderable = true;
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, Found },       // ideal tile, not ready
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 7, 0, 0 } }, NotFound },    // children
-                  GetTileDataAction{ { 7, { 7, 0, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 0 } }, NotFound },    // ...
-                  GetTileDataAction{ { 7, { 7, 1, 1 } }, NotFound },    // ...
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, Found },       // ascent
-                  RetainTileDataAction{ { 5, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, Found },       // ...
-                  RetainTileDataAction{ { 4, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, Found },       // ...
-                  RetainTileDataAction{ { 3, { 3, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, Found },       // ideal tile, not ready
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 7, 0, 0 } }, NotFound },    // children
+                  GetTileDataAction{ { 7, 0, { 7, 0, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 0 } }, NotFound },    // ...
+                  GetTileDataAction{ { 7, 0, { 7, 1, 1 } }, NotFound },    // ...
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, Found },       // ascent
+                  RetainTileDataAction{ { 5, 0, { 5, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, Found },       // ...
+                  RetainTileDataAction{ { 4, 0, { 4, 0, 0 } }, Resource::Necessity::Optional }, //
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, Found },       // ...
+                  RetainTileDataAction{ { 3, 0, { 3, 0, 0 } }, Resource::Necessity::Optional }, //
                   RenderTileAction{ { 3, 0, 0 }, *tile_3_3_0_0 },       //
               }),
               log);
@@ -1238,24 +1236,24 @@ TEST(UpdateRenderables, LoadRequiredIfIdealTileCantBeFound) {
     source.zoomRange.max = 6;
     source.idealTiles.emplace(UnwrappedTileID{ 6, 0, 0 });
 
-    auto tile_6_6_0_0 = source.createTileData(OverscaledTileID{ 6, { 6, 0, 0 } });
+    auto tile_6_6_0_0 = source.createTileData(OverscaledTileID{ 6, 0, { 6, 0, 0 } });
     tile_6_6_0_0->triedOptional = true;
     tile_6_6_0_0->loaded = true;
 
     algorithm::updateRenderables(getTileData, createTileData, retainTileData, renderTile,
                                  source.idealTiles, source.zoomRange, 6);
     EXPECT_EQ(ActionLog({
-                  GetTileDataAction{ { 6, { 6, 0, 0 } }, Found }, // ideal tile, not found
-                  RetainTileDataAction{ { 6, { 6, 0, 0 } }, Resource::Necessity::Required }, //
-                  GetTileDataAction{ { 7, { 6, 0, 0 } }, NotFound }, // overzoomed child
-                  GetTileDataAction{ { 5, { 5, 0, 0 } }, NotFound }, // ascent
-                  CreateTileDataAction{ { 5, { 5, 0, 0 } } },
-                  RetainTileDataAction{ { 5, { 5, 0, 0 } }, Resource::Necessity::Required },
-                  GetTileDataAction{ { 4, { 4, 0, 0 } }, NotFound }, // ...
-                  GetTileDataAction{ { 3, { 3, 0, 0 } }, NotFound }, // ...
-                  GetTileDataAction{ { 2, { 2, 0, 0 } }, NotFound }, // ...
-                  GetTileDataAction{ { 1, { 1, 0, 0 } }, NotFound }, // ...
-                  GetTileDataAction{ { 0, { 0, 0, 0 } }, NotFound }, // ...
+                  GetTileDataAction{ { 6, 0, { 6, 0, 0 } }, Found }, // ideal tile, not found
+                  RetainTileDataAction{ { 6, 0, { 6, 0, 0 } }, Resource::Necessity::Required }, //
+                  GetTileDataAction{ { 7, 0, { 6, 0, 0 } }, NotFound }, // overzoomed child
+                  GetTileDataAction{ { 5, 0, { 5, 0, 0 } }, NotFound }, // ascent
+                  CreateTileDataAction{ { 5, 0, { 5, 0, 0 } } },
+                  RetainTileDataAction{ { 5, 0, { 5, 0, 0 } }, Resource::Necessity::Required },
+                  GetTileDataAction{ { 4, 0, { 4, 0, 0 } }, NotFound }, // ...
+                  GetTileDataAction{ { 3, 0, { 3, 0, 0 } }, NotFound }, // ...
+                  GetTileDataAction{ { 2, 0, { 2, 0, 0 } }, NotFound }, // ...
+                  GetTileDataAction{ { 1, 0, { 1, 0, 0 } }, NotFound }, // ...
+                  GetTileDataAction{ { 0, 0, { 0, 0, 0 } }, NotFound }, // ...
               }),
               log);
 }
diff --git a/test/tile/tile_id.test.cpp b/test/tile/tile_id.test.cpp
index 1ef19fea0e..2f328b78d7 100644
--- a/test/tile/tile_id.test.cpp
+++ b/test/tile/tile_id.test.cpp
@@ -127,17 +127,17 @@ TEST(TileID, Canonical) {
 TEST(TileID, Overscaled) {
     EXPECT_TRUE(OverscaledTileID(4, 2, 3) == OverscaledTileID(4, 2, 3));
     EXPECT_FALSE(OverscaledTileID(4, 2, 3) != OverscaledTileID(4, 2, 3));
-    EXPECT_TRUE(OverscaledTileID(4, { 4, 2, 3 }) == OverscaledTileID(4, 2, 3));
-    EXPECT_FALSE(OverscaledTileID(4, { 4, 2, 3 }) != OverscaledTileID(4, 2, 3));
-    EXPECT_TRUE(OverscaledTileID(4, 2, 3) == OverscaledTileID(4, { 4, 2, 3 }));
-    EXPECT_FALSE(OverscaledTileID(4, 2, 3) != OverscaledTileID(4, { 4, 2, 3 }));
-
-    EXPECT_TRUE(OverscaledTileID(4, 2, 3) != OverscaledTileID(5, { 4, 2, 3 }));
-    EXPECT_FALSE(OverscaledTileID(4, 2, 3) == OverscaledTileID(5, { 4, 2, 3 }));
-    EXPECT_TRUE(OverscaledTileID(4, 2, 3) != OverscaledTileID(6, { 4, 2, 3 }));
-    EXPECT_FALSE(OverscaledTileID(4, 2, 3) == OverscaledTileID(6, { 4, 2, 3 }));
-    EXPECT_TRUE(OverscaledTileID(4, 2, 3) != OverscaledTileID(7, { 4, 2, 3 }));
-    EXPECT_FALSE(OverscaledTileID(4, 2, 3) == OverscaledTileID(7, { 4, 2, 3 }));
+    EXPECT_TRUE(OverscaledTileID(4, 0, { 4, 2, 3 }) == OverscaledTileID(4, 2, 3));
+    EXPECT_FALSE(OverscaledTileID(4, 0, { 4, 2, 3 }) != OverscaledTileID(4, 2, 3));
+    EXPECT_TRUE(OverscaledTileID(4, 2, 3) == OverscaledTileID(4, 0, { 4, 2, 3 }));
+    EXPECT_FALSE(OverscaledTileID(4, 2, 3) != OverscaledTileID(4, 0, { 4, 2, 3 }));
+
+    EXPECT_TRUE(OverscaledTileID(4, 2, 3) != OverscaledTileID(5, 0, { 4, 2, 3 }));
+    EXPECT_FALSE(OverscaledTileID(4, 2, 3) == OverscaledTileID(5, 0, { 4, 2, 3 }));
+    EXPECT_TRUE(OverscaledTileID(4, 2, 3) != OverscaledTileID(6, 0, { 4, 2, 3 }));
+    EXPECT_FALSE(OverscaledTileID(4, 2, 3) == OverscaledTileID(6, 0, { 4, 2, 3 }));
+    EXPECT_TRUE(OverscaledTileID(4, 2, 3) != OverscaledTileID(7, 0, { 4, 2, 3 }));
+    EXPECT_FALSE(OverscaledTileID(4, 2, 3) == OverscaledTileID(7, 0, { 4, 2, 3 }));
 
     EXPECT_TRUE(OverscaledTileID(4, 2, 3) != OverscaledTileID(4, 2, 4));
     EXPECT_FALSE(OverscaledTileID(4, 2, 3) == OverscaledTileID(4, 2, 4));
@@ -146,70 +146,70 @@ TEST(TileID, Overscaled) {
     EXPECT_TRUE(OverscaledTileID(4, 2, 3) != OverscaledTileID(5, 2, 3));
     EXPECT_FALSE(OverscaledTileID(4, 2, 3) == OverscaledTileID(5, 2, 3));
 
-    EXPECT_TRUE(OverscaledTileID(7, { 4, 2, 3 }) == OverscaledTileID(7, { 4, 2, 3 }));
-    EXPECT_FALSE(OverscaledTileID(7, { 4, 2, 3 }) != OverscaledTileID(7, { 4, 2, 3 }));
+    EXPECT_TRUE(OverscaledTileID(7, 0, { 4, 2, 3 }) == OverscaledTileID(7, 0, { 4, 2, 3 }));
+    EXPECT_FALSE(OverscaledTileID(7, 0, { 4, 2, 3 }) != OverscaledTileID(7, 0, { 4, 2, 3 }));
 
     EXPECT_FALSE(OverscaledTileID(4, 2, 3) < OverscaledTileID(4, 2, 3));
-    EXPECT_TRUE(OverscaledTileID(4, 2, 3) < OverscaledTileID(5, { 4, 2, 3 }));
-    EXPECT_FALSE(OverscaledTileID(5, { 4, 2, 3 }) < OverscaledTileID(4, 2, 3));
-    EXPECT_TRUE(OverscaledTileID(4, 2, 3) < OverscaledTileID(6, { 4, 2, 3 }));
-    EXPECT_FALSE(OverscaledTileID(6, { 4, 2, 3 }) < OverscaledTileID(4, 2, 3));
-    EXPECT_TRUE(OverscaledTileID(4, 2, 3) < OverscaledTileID(7, { 4, 2, 3 }));
-    EXPECT_FALSE(OverscaledTileID(7, { 4, 2, 3 }) < OverscaledTileID(4, 2, 3));
-
-    EXPECT_EQ(8u, OverscaledTileID(7, { 4, 2, 3 }).overscaleFactor());
-    EXPECT_EQ(4u, OverscaledTileID(6, { 4, 2, 3 }).overscaleFactor());
-    EXPECT_EQ(2u, OverscaledTileID(5, { 4, 2, 3 }).overscaleFactor());
-    EXPECT_EQ(1u, OverscaledTileID(4, { 4, 2, 3 }).overscaleFactor());
-    EXPECT_EQ(2147483648u, OverscaledTileID(31, { 0, 0, 0 }).overscaleFactor());
-
-    EXPECT_EQ(OverscaledTileID(0, { 0, 0, 0 }), OverscaledTileID(4, 2, 3).scaledTo(0));
-    EXPECT_EQ(OverscaledTileID(1, { 1, 0, 0 }), OverscaledTileID(4, 2, 3).scaledTo(1));
-    EXPECT_EQ(OverscaledTileID(2, { 2, 0, 0 }), OverscaledTileID(4, 2, 3).scaledTo(2));
-    EXPECT_EQ(OverscaledTileID(3, { 3, 1, 1 }), OverscaledTileID(4, 2, 3).scaledTo(3));
-    EXPECT_EQ(OverscaledTileID(4, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(4));
-    EXPECT_EQ(OverscaledTileID(5, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(5));
-    EXPECT_EQ(OverscaledTileID(6, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(6));
-    EXPECT_EQ(OverscaledTileID(7, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(7));
-    EXPECT_EQ(OverscaledTileID(8, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(8));
-    EXPECT_EQ(OverscaledTileID(32, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(32));
-
-    EXPECT_EQ(UnwrappedTileID(0, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).unwrapTo(0));
-    EXPECT_EQ(UnwrappedTileID(-1, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).unwrapTo(-1));
-    EXPECT_EQ(UnwrappedTileID(1, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).unwrapTo(1));
-    EXPECT_EQ(UnwrappedTileID(0, { 4, 2, 3 }), OverscaledTileID(5, { 4, 2, 3 }).unwrapTo(0));
-    EXPECT_EQ(UnwrappedTileID(-1, { 4, 2, 3 }), OverscaledTileID(5, { 4, 2, 3 }).unwrapTo(-1));
-    EXPECT_EQ(UnwrappedTileID(1, { 4, 2, 3 }), OverscaledTileID(5, { 4, 2, 3 }).unwrapTo(1));
+    EXPECT_TRUE(OverscaledTileID(4, 2, 3) < OverscaledTileID(5, 0, { 4, 2, 3 }));
+    EXPECT_FALSE(OverscaledTileID(5, 0, { 4, 2, 3 }) < OverscaledTileID(4, 2, 3));
+    EXPECT_TRUE(OverscaledTileID(4, 2, 3) < OverscaledTileID(6, 0, { 4, 2, 3 }));
+    EXPECT_FALSE(OverscaledTileID(6, 0, { 4, 2, 3 }) < OverscaledTileID(4, 2, 3));
+    EXPECT_TRUE(OverscaledTileID(4, 2, 3) < OverscaledTileID(7,0,  { 4, 2, 3 }));
+    EXPECT_FALSE(OverscaledTileID(7, 0, { 4, 2, 3 }) < OverscaledTileID(4, 2, 3));
+
+    EXPECT_EQ(8u, OverscaledTileID(7, 0, { 4, 2, 3 }).overscaleFactor());
+    EXPECT_EQ(4u, OverscaledTileID(6, 0, { 4, 2, 3 }).overscaleFactor());
+    EXPECT_EQ(2u, OverscaledTileID(5, 0, { 4, 2, 3 }).overscaleFactor());
+    EXPECT_EQ(1u, OverscaledTileID(4, 0, { 4, 2, 3 }).overscaleFactor());
+    EXPECT_EQ(2147483648u, OverscaledTileID(31, 0, { 0, 0, 0 }).overscaleFactor());
+
+    EXPECT_EQ(OverscaledTileID(0, 0, { 0, 0, 0 }), OverscaledTileID(4, 2, 3).scaledTo(0));
+    EXPECT_EQ(OverscaledTileID(1, 0, { 1, 0, 0 }), OverscaledTileID(4, 2, 3).scaledTo(1));
+    EXPECT_EQ(OverscaledTileID(2, 0, { 2, 0, 0 }), OverscaledTileID(4, 2, 3).scaledTo(2));
+    EXPECT_EQ(OverscaledTileID(3, 0, { 3, 1, 1 }), OverscaledTileID(4, 2, 3).scaledTo(3));
+    EXPECT_EQ(OverscaledTileID(4, 0, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(4));
+    EXPECT_EQ(OverscaledTileID(5, 0, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(5));
+    EXPECT_EQ(OverscaledTileID(6, 0, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(6));
+    EXPECT_EQ(OverscaledTileID(7, 0, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(7));
+    EXPECT_EQ(OverscaledTileID(8, 0, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(8));
+    EXPECT_EQ(OverscaledTileID(32, 0, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).scaledTo(32));
+
+    EXPECT_EQ(UnwrappedTileID(0, { 4, 2, 3 }), OverscaledTileID(4, 2, 3).toUnwrapped());
+    EXPECT_EQ(UnwrappedTileID(-1, { 4, 2, 3 }), OverscaledTileID(4, -1, { 4, 2, 3 }).toUnwrapped());
+    EXPECT_EQ(UnwrappedTileID(1, { 4, 2, 3 }), OverscaledTileID(4, 1, { 4, 2, 3 }).toUnwrapped());
+    EXPECT_EQ(UnwrappedTileID(0, { 4, 2, 3 }), OverscaledTileID(5, 0, { 4, 2, 3 }).toUnwrapped());
+    EXPECT_EQ(UnwrappedTileID(-1, { 4, 2, 3 }), OverscaledTileID(5, -1, { 4, 2, 3 }).toUnwrapped());
+    EXPECT_EQ(UnwrappedTileID(1, { 4, 2, 3 }), OverscaledTileID(5, 1, { 4, 2, 3 }).toUnwrapped());
 
     EXPECT_FALSE(OverscaledTileID(2, 0, 0).isChildOf(OverscaledTileID(3, 1, 1)));
     EXPECT_FALSE(OverscaledTileID(3, 1, 1).isChildOf(OverscaledTileID(3, 1, 1)));
     EXPECT_TRUE(OverscaledTileID(4, 2, 3).isChildOf(OverscaledTileID(3, 1, 1)));
-    EXPECT_TRUE(OverscaledTileID(5, { 4, 2, 3 }).isChildOf(OverscaledTileID(3, 1, 1)));
-    EXPECT_TRUE(OverscaledTileID(6, { 4, 2, 3 }).isChildOf(OverscaledTileID(3, 1, 1)));
-    EXPECT_TRUE(OverscaledTileID(7, { 4, 2, 3 }).isChildOf(OverscaledTileID(3, 1, 1)));
-
-    EXPECT_FALSE(OverscaledTileID(2, 0, 0).isChildOf(OverscaledTileID(5, { 4, 2, 3 })));
-    EXPECT_FALSE(OverscaledTileID(3, 1, 1).isChildOf(OverscaledTileID(5, { 4, 2, 3 })));
-    EXPECT_FALSE(OverscaledTileID(4, 2, 3).isChildOf(OverscaledTileID(5, { 4, 2, 3 })));
-    EXPECT_FALSE(OverscaledTileID(5, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, { 4, 2, 3 })));
-    EXPECT_TRUE(OverscaledTileID(6, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, { 4, 2, 3 })));
-    EXPECT_TRUE(OverscaledTileID(7, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, { 4, 2, 3 })));
-
-    EXPECT_FALSE(OverscaledTileID(2, 0, 0).isChildOf(OverscaledTileID(6, { 4, 2, 3 })));
-    EXPECT_FALSE(OverscaledTileID(3, 1, 1).isChildOf(OverscaledTileID(6, { 4, 2, 3 })));
-    EXPECT_FALSE(OverscaledTileID(4, 2, 3).isChildOf(OverscaledTileID(6, { 4, 2, 3 })));
-    EXPECT_FALSE(OverscaledTileID(5, { 4, 2, 3 }).isChildOf(OverscaledTileID(6, { 4, 2, 3 })));
-    EXPECT_FALSE(OverscaledTileID(6, { 4, 2, 3 }).isChildOf(OverscaledTileID(6, { 4, 2, 3 })));
-    EXPECT_TRUE(OverscaledTileID(7, { 4, 2, 3 }).isChildOf(OverscaledTileID(6, { 4, 2, 3 })));
-
-    EXPECT_FALSE(OverscaledTileID(2, 0, 0).isChildOf(OverscaledTileID(5, { 4, 0, 0 })));
-    EXPECT_FALSE(OverscaledTileID(3, 1, 1).isChildOf(OverscaledTileID(5, { 4, 0, 0 })));
-    EXPECT_FALSE(OverscaledTileID(4, 2, 3).isChildOf(OverscaledTileID(5, { 4, 0, 0 })));
-    EXPECT_FALSE(OverscaledTileID(5, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, { 4, 0, 0 })));
-    EXPECT_FALSE(OverscaledTileID(6, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, { 4, 0, 0 })));
-    EXPECT_FALSE(OverscaledTileID(7, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, { 4, 0, 0 })));
-
-    EXPECT_FALSE(OverscaledTileID(4, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, { 3, 1, 1 })));
+    EXPECT_TRUE(OverscaledTileID(5, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(3, 1, 1)));
+    EXPECT_TRUE(OverscaledTileID(6, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(3, 1, 1)));
+    EXPECT_TRUE(OverscaledTileID(7, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(3, 1, 1)));
+
+    EXPECT_FALSE(OverscaledTileID(2, 0, 0).isChildOf(OverscaledTileID(5, 0, { 4, 2, 3 })));
+    EXPECT_FALSE(OverscaledTileID(3, 1, 1).isChildOf(OverscaledTileID(5, 0, { 4, 2, 3 })));
+    EXPECT_FALSE(OverscaledTileID(4, 2, 3).isChildOf(OverscaledTileID(5, 0, { 4, 2, 3 })));
+    EXPECT_FALSE(OverscaledTileID(5, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, 0, { 4, 2, 3 })));
+    EXPECT_TRUE(OverscaledTileID(6, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, 0, { 4, 2, 3 })));
+    EXPECT_TRUE(OverscaledTileID(7, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, 0, { 4, 2, 3 })));
+
+    EXPECT_FALSE(OverscaledTileID(2, 0, 0).isChildOf(OverscaledTileID(6, 0, { 4, 2, 3 })));
+    EXPECT_FALSE(OverscaledTileID(3, 1, 1).isChildOf(OverscaledTileID(6, 0, { 4, 2, 3 })));
+    EXPECT_FALSE(OverscaledTileID(4, 2, 3).isChildOf(OverscaledTileID(6, 0, { 4, 2, 3 })));
+    EXPECT_FALSE(OverscaledTileID(5, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(6, 0, { 4, 2, 3 })));
+    EXPECT_FALSE(OverscaledTileID(6, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(6, 0, { 4, 2, 3 })));
+    EXPECT_TRUE(OverscaledTileID(7, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(6, 0, { 4, 2, 3 })));
+
+    EXPECT_FALSE(OverscaledTileID(2, 0, 0).isChildOf(OverscaledTileID(5, 0, { 4, 0, 0 })));
+    EXPECT_FALSE(OverscaledTileID(3, 1, 1).isChildOf(OverscaledTileID(5, 0, { 4, 0, 0 })));
+    EXPECT_FALSE(OverscaledTileID(4, 2, 3).isChildOf(OverscaledTileID(5, 0, { 4, 0, 0 })));
+    EXPECT_FALSE(OverscaledTileID(5, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, 0, { 4, 0, 0 })));
+    EXPECT_FALSE(OverscaledTileID(6, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, 0, { 4, 0, 0 })));
+    EXPECT_FALSE(OverscaledTileID(7, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, 0, { 4, 0, 0 })));
+
+    EXPECT_FALSE(OverscaledTileID(4, 0, { 4, 2, 3 }).isChildOf(OverscaledTileID(5, 0, { 3, 1, 1 })));
 }
 
 TEST(TileID, Unwrapped) {
@@ -273,10 +273,10 @@ TEST(TileID, Unwrapped) {
     EXPECT_FALSE(UnwrappedTileID(0, 1, 0) < UnwrappedTileID(1, 0, 0));
     EXPECT_FALSE(UnwrappedTileID(5, 3, 6) < UnwrappedTileID(5, 3, 6));
 
-    EXPECT_EQ(OverscaledTileID(4, { 4, 2, 3 }), UnwrappedTileID(4, 2, 3).overscaleTo(4));
-    EXPECT_EQ(OverscaledTileID(5, { 4, 2, 3 }), UnwrappedTileID(4, 2, 3).overscaleTo(5));
-    EXPECT_EQ(OverscaledTileID(6, { 4, 2, 3 }), UnwrappedTileID(4, 2, 3).overscaleTo(6));
-    EXPECT_EQ(OverscaledTileID(32, { 4, 2, 3 }), UnwrappedTileID(4, 2, 3).overscaleTo(32));
+    EXPECT_EQ(OverscaledTileID(4, 0, { 4, 2, 3 }), UnwrappedTileID(4, 2, 3).overscaleTo(4));
+    EXPECT_EQ(OverscaledTileID(5, 0, { 4, 2, 3 }), UnwrappedTileID(4, 2, 3).overscaleTo(5));
+    EXPECT_EQ(OverscaledTileID(6, 0, { 4, 2, 3 }), UnwrappedTileID(4, 2, 3).overscaleTo(6));
+    EXPECT_EQ(OverscaledTileID(32, 0, { 4, 2, 3 }), UnwrappedTileID(4, 2, 3).overscaleTo(32));
 
     EXPECT_EQ(UnwrappedTileID(-1, { 1, 0, 0 }), UnwrappedTileID(1, -2, 0));
     EXPECT_EQ(UnwrappedTileID(-1, { 1, 0, 1 }), UnwrappedTileID(1, -2, 1));