implement backfill border

5 files changed, 57 insertions, 42 deletions

diff --git a/src/mbgl/renderer/render_source.hpp b/src/mbgl/renderer/render_source.hpp
index 8c84af4f1e..9f9742b5a7 100644
--- a/src/mbgl/renderer/render_source.hpp
+++ b/src/mbgl/renderer/render_source.hpp
@@ -84,7 +84,7 @@ protected:
 
     bool enabled = false;
 
-    void onTileChanged(Tile&) final;
+    virtual void onTileChanged(Tile&);
     void onTileError(Tile&, std::exception_ptr) final;
 };
 
diff --git a/src/mbgl/renderer/sources/render_raster_dem_source.cpp b/src/mbgl/renderer/sources/render_raster_dem_source.cpp
index 5679aa23df..2678e112ba 100644
--- a/src/mbgl/renderer/sources/render_raster_dem_source.cpp
+++ b/src/mbgl/renderer/sources/render_raster_dem_source.cpp
@@ -2,6 +2,8 @@
 #include <mbgl/renderer/render_tile.hpp>
 #include <mbgl/tile/raster_dem_tile.hpp>
 #include <mbgl/algorithm/update_tile_masks.hpp>
+#include <mbgl/geometry/dem_pyramid.hpp>
+#include <mbgl/renderer/buckets/hillshade_bucket.hpp>
 
 namespace mbgl {
 
@@ -55,51 +57,54 @@ void RenderRasterDEMSource::update(Immutable<style::Source::Impl> baseImpl_,
                        [&] (const OverscaledTileID& tileID) {
                            return std::make_unique<RasterDEMTile>(tileID, parameters, *tileset);
                        });
+}
+
+static void fillBorder(const RasterDEMTile& tile, const RasterDEMTile& borderTile){
+    int dx = borderTile.id.canonical.x - tile.id.canonical.x;
+    const int8_t dy = borderTile.id.canonical.y - tile.id.canonical.y;
+    const uint32_t dim = pow(2, tile.id.canonical.z);
+    if (dx == 0 && dy == 0) return;
+    if (std::abs(dy) > 1) return;
+    // neighbor is in another world wrap
+    if (std::abs(dx) > 1) {
+        if (std::abs(int(dx + dim)) == 1) {
+            dx += dim;
+        } else if (std::abs(int(dx - dim)) == 1) {
+            dx -= dim;
+        }
+    }
+    HillshadeBucket* borderBucket = borderTile.getBucket();
+    HillshadeBucket* tileBucket = tile.getBucket();
+    DEMPyramid* tileDEM = tileBucket->getDEMPyramid();
+    DEMPyramid* borderDEM = borderBucket->getDEMPyramid();
+
+    if (tileDEM->isLoaded() && borderDEM->isLoaded()){
+        tileDEM->backfillBorder(*borderDEM, dx, dy);
+    }
+    tileBucket->prepared = false;
+    borderBucket->prepared = false;
+}
+
+void RenderRasterDEMSource::onTileChanged(Tile& tile){
+    const RasterDEMTile& demtile = static_cast<RasterDEMTile&>(tile);
     auto rendertiles = getRenderTiles();
-    std::sort(rendertiles.begin(), rendertiles.end(),
-              [](const RenderTile& a, const RenderTile& b) { return a.id < b.id; });
-
-    for (auto& rt : rendertiles) {
-        RasterDEMTile& demtile = static_cast<RasterDEMTile&>(rt.get().tile);
-        if (!demtile.isBackfilled()) {
-            bool lastBackfill = true;
-            for (auto& pair : demtile.neighboringTiles) {
-                // the current neighboring tile has not been backfilled yet
-                if (!pair.second) {
-                    const auto renderableNeighbor = std::find_if(rendertiles.begin(), rendertiles.end(), [&pair] (const RenderTile& rt){
-                        return rt.id.canonical == pair.first.canonical;
-                    });
-
-                    if (renderableNeighbor != rendertiles.end()) {
-                        const RasterDEMTile& borderTile = static_cast<RasterDEMTile&>(renderableNeighbor->get().tile);
-                        int dx = borderTile.id.canonical.x - demtile.id.canonical.x;
-                        const int8_t dy = borderTile.id.canonical.y - demtile.id.canonical.y;
-                        const uint32_t dim = pow(2, demtile.id.canonical.z);
-                        if (dx == 0 && dy == 0) continue;
-                        if (std::abs(dy) > 1) continue;
-                        // neighbor is in another world wrap
-                        if (std::abs(dx) > 1) {
-                            if (std::abs(int(dx + dim)) == 1) {
-                                dx += dim;
-                            } else if (std::abs(int(dx - dim)) == 1) {
-                                dx -= dim;
-                            }
-                        }
-
-//                        HillshadeBucket* borderBucket = borderTile.getBucket(hillshadeLayer->baseImpl)
-//                        if (!borderTile.dem || !tile.dem) return;
-//                        tile.dem.backfillBorder(borderTile.dem, dx, dy);
-//                        if (tile.neighboringTiles && tile.neighboringTiles[borderId])
-//                            tile.neighboringTiles[borderId].backfilled = true;
-
-                        pair.second = true;
-                    } else {
-                        lastBackfill = false;
-                    }
+
+    if (tile.isLoaded() && demtile.isBackfilled()) {
+        for (auto& pair: demtile.neighboringTiles) {
+            if (!pair.second) {
+                const auto renderableNeighbor = std::find_if(rendertiles.begin(), rendertiles.end(), [&pair] (const RenderTile& rt){
+                    return rt.id.canonical == pair.first.canonical;
+                });
+
+                if (renderableNeighbor != rendertiles.end()) {
+                    const RasterDEMTile& borderTile = static_cast<RasterDEMTile&>(renderableNeighbor->get().tile);
+                    fillBorder(demtile, borderTile);
+                    fillBorder(borderTile, demtile);
                 }
             }
         }
     }
+    RenderSource::onTileChanged(tile);
 }
 
 void RenderRasterDEMSource::startRender(PaintParameters& parameters) {
diff --git a/src/mbgl/renderer/sources/render_raster_dem_source.hpp b/src/mbgl/renderer/sources/render_raster_dem_source.hpp
index ef2348fdd9..8d90e081a3 100644
--- a/src/mbgl/renderer/sources/render_raster_dem_source.hpp
+++ b/src/mbgl/renderer/sources/render_raster_dem_source.hpp
@@ -41,6 +41,9 @@ private:
 
     TilePyramid tilePyramid;
     optional<std::vector<std::string>> tileURLTemplates;
+
+protected:
+    void onTileChanged(Tile&);
 };
 
 template <>
diff --git a/src/mbgl/tile/raster_dem_tile.cpp b/src/mbgl/tile/raster_dem_tile.cpp
index f8335bef3d..6e6b77aaff 100644
--- a/src/mbgl/tile/raster_dem_tile.cpp
+++ b/src/mbgl/tile/raster_dem_tile.cpp
@@ -20,7 +20,7 @@ RasterDEMTile::RasterDEMTile(const OverscaledTileID& id_,
       mailbox(std::make_shared<Mailbox>(*Scheduler::GetCurrent())),
       worker(parameters.workerScheduler,
              ActorRef<RasterDEMTile>(*this, mailbox)) {
-          
+
      const CanonicalTileID canonical = id_.canonical;
      const u_int32_t dim = pow(2, canonical.z);
      const u_int32_t px = (canonical.x - 1 + dim) % dim;
@@ -92,10 +92,16 @@ void RasterDEMTile::upload(gl::Context& context) {
     }
 }
 
+
 Bucket* RasterDEMTile::getBucket(const style::Layer::Impl&) const {
     return bucket.get();
 }
 
+HillshadeBucket* RasterDEMTile::getBucket() const {
+    return bucket.get();
+}
+
+
 void RasterDEMTile::setMask(TileMask&& mask) {
     if (bucket) {
         bucket->setMask(std::move(mask));
diff --git a/src/mbgl/tile/raster_dem_tile.hpp b/src/mbgl/tile/raster_dem_tile.hpp
index e8ac7ce893..178f0da596 100644
--- a/src/mbgl/tile/raster_dem_tile.hpp
+++ b/src/mbgl/tile/raster_dem_tile.hpp
@@ -32,6 +32,7 @@ public:
 
     void upload(gl::Context&) override;
     Bucket* getBucket(const style::Layer::Impl&) const override;
+    HillshadeBucket* getBucket() const;
     
     std::unordered_map<OverscaledTileID, bool> neighboringTiles;