[core] Override default prefetch delta if source has it's own setting

9 files changed, 94 insertions, 81 deletions

diff --git a/src/mbgl/annotation/render_annotation_source.cpp b/src/mbgl/annotation/render_annotation_source.cpp
index e3acfcb3c0..85665961d3 100644
--- a/src/mbgl/annotation/render_annotation_source.cpp
+++ b/src/mbgl/annotation/render_annotation_source.cpp
@@ -28,19 +28,19 @@ void RenderAnnotationSource::update(Immutable<style::Source::Impl> baseImpl_,
 
     enabled = needsRendering;
 
-    tilePyramid.update(layers,
-                       needsRendering,
-                       needsRelayout,
-                       parameters,
-                       SourceType::Annotations,
-                       util::tileSize,
-                       // Zoom level 16 is typically sufficient for annotations.
-                       // See https://github.com/mapbox/mapbox-gl-native/issues/10197
-                       { 0, 16 },
-                       optional<LatLngBounds> {},
-                       [&] (const OverscaledTileID& tileID) {
-                           return std::make_unique<AnnotationTile>(tileID, parameters);
-                       });
+    tilePyramid.update(
+        layers,
+        needsRendering,
+        needsRelayout,
+        parameters,
+        SourceType::Annotations,
+        util::tileSize,
+        // Zoom level 16 is typically sufficient for annotations.
+        // See https://github.com/mapbox/mapbox-gl-native/issues/10197
+        {0, 16},
+        optional<LatLngBounds>{},
+        [&](const OverscaledTileID& tileID) { return std::make_unique<AnnotationTile>(tileID, parameters); },
+        baseImpl->getPrefetchZoomDelta());
 }
 
 std::unordered_map<std::string, std::vector<Feature>>
diff --git a/src/mbgl/renderer/sources/render_custom_geometry_source.cpp b/src/mbgl/renderer/sources/render_custom_geometry_source.cpp
index 6b81658370..ea6f5c3102 100644
--- a/src/mbgl/renderer/sources/render_custom_geometry_source.cpp
+++ b/src/mbgl/renderer/sources/render_custom_geometry_source.cpp
@@ -33,17 +33,20 @@ void RenderCustomGeometrySource::update(Immutable<style::Source::Impl> baseImpl_
         return;
     }
 
-    tilePyramid.update(layers,
-                       needsRendering,
-                       needsRelayout,
-                       parameters,
-                       SourceType::CustomVector,
-                       util::tileSize,
-                       impl().getZoomRange(),
-                       {},
-                       [&] (const OverscaledTileID& tileID) {
-                           return std::make_unique<CustomGeometryTile>(tileID, impl().id, parameters, impl().getTileOptions(), *tileLoader);
-                       });
+    tilePyramid.update(
+        layers,
+        needsRendering,
+        needsRelayout,
+        parameters,
+        SourceType::CustomVector,
+        util::tileSize,
+        impl().getZoomRange(),
+        {},
+        [&](const OverscaledTileID& tileID) {
+            return std::make_unique<CustomGeometryTile>(
+                tileID, impl().id, parameters, impl().getTileOptions(), *tileLoader);
+        },
+        baseImpl->getPrefetchZoomDelta());
 }
 
 } // namespace mbgl
diff --git a/src/mbgl/renderer/sources/render_geojson_source.cpp b/src/mbgl/renderer/sources/render_geojson_source.cpp
index 94d171cf18..45a91e3fa0 100644
--- a/src/mbgl/renderer/sources/render_geojson_source.cpp
+++ b/src/mbgl/renderer/sources/render_geojson_source.cpp
@@ -103,17 +103,19 @@ void RenderGeoJSONSource::update(Immutable<style::Source::Impl> baseImpl_,
 
     if (!data_) return;
 
-    tilePyramid.update(layers,
-                       needsRendering,
-                       needsRelayout,
-                       parameters,
-                       SourceType::GeoJSON,
-                       util::tileSize,
-                       impl().getZoomRange(),
-                       optional<LatLngBounds>{},
-                       [&, data_](const OverscaledTileID& tileID) {
-                           return std::make_unique<GeoJSONTile>(tileID, impl().id, parameters, data_);
-                       });
+    tilePyramid.update(
+        layers,
+        needsRendering,
+        needsRelayout,
+        parameters,
+        SourceType::GeoJSON,
+        util::tileSize,
+        impl().getZoomRange(),
+        optional<LatLngBounds>{},
+        [&, data_](const OverscaledTileID& tileID) {
+            return std::make_unique<GeoJSONTile>(tileID, impl().id, parameters, data_);
+        },
+        baseImpl->getPrefetchZoomDelta());
 }
 
 mapbox::util::variant<Value, FeatureCollection>
diff --git a/src/mbgl/renderer/sources/render_raster_dem_source.cpp b/src/mbgl/renderer/sources/render_raster_dem_source.cpp
index fb6e343670..953484f6c6 100644
--- a/src/mbgl/renderer/sources/render_raster_dem_source.cpp
+++ b/src/mbgl/renderer/sources/render_raster_dem_source.cpp
@@ -27,17 +27,17 @@ void RenderRasterDEMSource::updateInternal(const Tileset& tileset,
                                            const bool needsRendering,
                                            const bool needsRelayout,
                                            const TileParameters& parameters) {
-    tilePyramid.update(layers,
-                       needsRendering,
-                       needsRelayout,
-                       parameters,
-                       SourceType::RasterDEM,
-                       impl().getTileSize(),
-                       tileset.zoomRange,
-                       tileset.bounds,
-                       [&] (const OverscaledTileID& tileID) {
-                           return std::make_unique<RasterDEMTile>(tileID, parameters, tileset);
-                       });
+    tilePyramid.update(
+        layers,
+        needsRendering,
+        needsRelayout,
+        parameters,
+        SourceType::RasterDEM,
+        impl().getTileSize(),
+        tileset.zoomRange,
+        tileset.bounds,
+        [&](const OverscaledTileID& tileID) { return std::make_unique<RasterDEMTile>(tileID, parameters, tileset); },
+        baseImpl->getPrefetchZoomDelta());
     algorithm::updateTileMasks(tilePyramid.getRenderedTiles());
 }
 
diff --git a/src/mbgl/renderer/sources/render_raster_source.cpp b/src/mbgl/renderer/sources/render_raster_source.cpp
index 408f8a4e11..7ef7b26459 100644
--- a/src/mbgl/renderer/sources/render_raster_source.cpp
+++ b/src/mbgl/renderer/sources/render_raster_source.cpp
@@ -25,17 +25,17 @@ void RenderRasterSource::updateInternal(const Tileset& tileset,
                                         const bool needsRendering,
                                         const bool needsRelayout,
                                         const TileParameters& parameters) {
-    tilePyramid.update(layers,
-                       needsRendering,
-                       needsRelayout,
-                       parameters,
-                       SourceType::Raster,
-                       impl().getTileSize(),
-                       tileset.zoomRange,
-                       tileset.bounds,
-                       [&] (const OverscaledTileID& tileID) {
-                           return std::make_unique<RasterTile>(tileID, parameters, tileset);
-                       });
+    tilePyramid.update(
+        layers,
+        needsRendering,
+        needsRelayout,
+        parameters,
+        SourceType::Raster,
+        impl().getTileSize(),
+        tileset.zoomRange,
+        tileset.bounds,
+        [&](const OverscaledTileID& tileID) { return std::make_unique<RasterTile>(tileID, parameters, tileset); },
+        baseImpl->getPrefetchZoomDelta());
     algorithm::updateTileMasks(tilePyramid.getRenderedTiles());
 }
 
diff --git a/src/mbgl/renderer/sources/render_vector_source.cpp b/src/mbgl/renderer/sources/render_vector_source.cpp
index 6e4fdede10..324599d45d 100644
--- a/src/mbgl/renderer/sources/render_vector_source.cpp
+++ b/src/mbgl/renderer/sources/render_vector_source.cpp
@@ -21,17 +21,19 @@ void RenderVectorSource::updateInternal(const Tileset& tileset,
                                         const bool needsRendering,
                                         const bool needsRelayout,
                                         const TileParameters& parameters) {
-    tilePyramid.update(layers,
-                       needsRendering,
-                       needsRelayout,
-                       parameters,
-                       SourceType::Vector,
-                       util::tileSize,
-                       tileset.zoomRange,
-                       tileset.bounds,
-                       [&] (const OverscaledTileID& tileID) {
-                           return std::make_unique<VectorTile>(tileID, baseImpl->id, parameters, tileset);
-                       });
+    tilePyramid.update(
+        layers,
+        needsRendering,
+        needsRelayout,
+        parameters,
+        SourceType::Vector,
+        util::tileSize,
+        tileset.zoomRange,
+        tileset.bounds,
+        [&](const OverscaledTileID& tileID) {
+            return std::make_unique<VectorTile>(tileID, baseImpl->id, parameters, tileset);
+        },
+        baseImpl->getPrefetchZoomDelta());
 }
 
 } // namespace mbgl
diff --git a/src/mbgl/renderer/tile_pyramid.cpp b/src/mbgl/renderer/tile_pyramid.cpp
index 586d3b5a8a..38d984bec4 100644
--- a/src/mbgl/renderer/tile_pyramid.cpp
+++ b/src/mbgl/renderer/tile_pyramid.cpp
@@ -57,7 +57,8 @@ void TilePyramid::update(const std::vector<Immutable<style::LayerProperties>>& l
                          const uint16_t tileSize,
                          const Range<uint8_t> zoomRange,
                          optional<LatLngBounds> bounds,
-                         std::function<std::unique_ptr<Tile> (const OverscaledTileID&)> createTile) {
+                         std::function<std::unique_ptr<Tile>(const OverscaledTileID&)> createTile,
+                         optional<uint8_t> sourcePrefetchZoomDelta) {
     // If we need a relayout, abandon any cached tiles; they're now stale.
     if (needsRelayout) {
         cache.clear();
@@ -105,8 +106,10 @@ void TilePyramid::update(const std::vector<Immutable<style::LayerProperties>>& l
         if (parameters.mode == MapMode::Continuous && type != style::SourceType::GeoJSON && type != style::SourceType::Annotations) {
             // Request lower zoom level tiles (if configured to do so) in an attempt
             // to show something on the screen faster at the cost of a little of bandwidth.
-            if (parameters.prefetchZoomDelta) {
-                panZoom = std::max<int32_t>(tileZoom - parameters.prefetchZoomDelta, zoomRange.min);
+            const uint8_t prefetchZoomDelta =
+                sourcePrefetchZoomDelta ? *sourcePrefetchZoomDelta : parameters.prefetchZoomDelta;
+            if (prefetchZoomDelta) {
+                panZoom = std::max<int32_t>(tileZoom - prefetchZoomDelta, zoomRange.min);
             }
 
             if (panZoom < idealZoom) {
diff --git a/src/mbgl/renderer/tile_pyramid.hpp b/src/mbgl/renderer/tile_pyramid.hpp
index 3b5cab5d6c..5f2bfd1ea9 100644
--- a/src/mbgl/renderer/tile_pyramid.hpp
+++ b/src/mbgl/renderer/tile_pyramid.hpp
@@ -41,7 +41,8 @@ public:
                 uint16_t tileSize,
                 Range<uint8_t> zoomRange,
                 optional<LatLngBounds> bounds,
-                std::function<std::unique_ptr<Tile> (const OverscaledTileID&)> createTile);
+                std::function<std::unique_ptr<Tile>(const OverscaledTileID&)> createTile,
+                optional<uint8_t> sourcePrefetchZoomDelta);
 
     const std::map<UnwrappedTileID, std::reference_wrapper<Tile>>& getRenderedTiles() const { return renderedTiles; }
     Tile* getTile(const OverscaledTileID&);
diff --git a/test/style/source.test.cpp b/test/style/source.test.cpp
index 0286aaaec3..dbc67681e9 100644
--- a/test/style/source.test.cpp
+++ b/test/style/source.test.cpp
@@ -765,15 +765,17 @@ public:
                         const bool needsRendering,
                         const bool needsRelayout,
                         const TileParameters& parameters) override {
-        tilePyramid.update(layers,
-                           needsRendering,
-                           needsRelayout,
-                           parameters,
-                           SourceType::Vector,
-                           util::tileSize,
-                           tileset.zoomRange,
-                           tileset.bounds,
-                           [&](const OverscaledTileID& tileID) { return std::make_unique<FakeTile>(*this, tileID); });
+        tilePyramid.update(
+            layers,
+            needsRendering,
+            needsRelayout,
+            parameters,
+            SourceType::Vector,
+            util::tileSize,
+            tileset.zoomRange,
+            tileset.bounds,
+            [&](const OverscaledTileID& tileID) { return std::make_unique<FakeTile>(*this, tileID); },
+            baseImpl->getPrefetchZoomDelta());
     }
 
     const optional<Tileset>& getTileset() const override {