[core] Switch from background to foreground placement

 - Background placement code now just generates static symbol buffers
 - Don't render GeometryTiles until their symbols are loaded. This is necessary for the CrossTileSymbolIndex to successfully prevent flicker.
 - SymbolInstances are transferred to SymbolBucket for use on foreground during collision detection
 - Symbols are sorted on foreground by sorting their index buffer but leaving vertex buffers intact (only works within one segment)
 - Vertical glyphs are generated at same time as horizontal glyphs. `reprojectLineLabels` chooses which one to use at render time and hides the other.
 - Icons are now always represented with a single collision box, even if they're placed along a line (this means their rotation alignment may be wrong, but the approach of representing them with multiple collision boxes wasn't very accurate either).
 - Generate vertices for new debug collision boxes and collision circles
 - Only add symbols within tile boundaries (reduces work, avoids double-draw)
 - Update symbol_projection.cpp to support line label projection calls from CollisionIndex.

1 files changed, 7 insertions, 4 deletions

diff --git a/src/mbgl/tile/geometry_tile_worker.hpp b/src/mbgl/tile/geometry_tile_worker.hpp
index 1425daa7a1..cc86248cec 100644
--- a/src/mbgl/tile/geometry_tile_worker.hpp
+++ b/src/mbgl/tile/geometry_tile_worker.hpp
@@ -4,7 +4,6 @@
 #include <mbgl/tile/tile_id.hpp>
 #include <mbgl/style/image_impl.hpp>
 #include <mbgl/text/glyph.hpp>
-#include <mbgl/text/placement_config.hpp>
 #include <mbgl/actor/actor_ref.hpp>
 #include <mbgl/util/optional.hpp>
 #include <mbgl/util/immutable.hpp>
@@ -28,14 +27,16 @@ public:
     GeometryTileWorker(ActorRef<GeometryTileWorker> self,
                        ActorRef<GeometryTile> parent,
                        OverscaledTileID,
+                       const std::string&,
                        const std::atomic<bool>&,
                        const MapMode,
-                       const float pixelRatio);
+                       const float pixelRatio,
+                       const bool showCollisionBoxes_);
     ~GeometryTileWorker();
 
     void setLayers(std::vector<Immutable<style::Layer::Impl>>, uint64_t correlationID);
     void setData(std::unique_ptr<const GeometryTileData>, uint64_t correlationID);
-    void setPlacementConfig(PlacementConfig, uint64_t correlationID);
+    void setShowCollisionBoxes(bool showCollisionBoxes_, uint64_t correlationID_);
     
     void onGlyphsAvailable(GlyphMap glyphs);
     void onImagesAvailable(ImageMap images, uint64_t imageCorrelationID);
@@ -57,6 +58,7 @@ private:
     ActorRef<GeometryTile> parent;
 
     const OverscaledTileID id;
+    const std::string sourceID;
     const std::atomic<bool>& obsolete;
     const MapMode mode;
     const float pixelRatio;
@@ -75,7 +77,6 @@ private:
     // Outer optional indicates whether we've received it or not.
     optional<std::vector<Immutable<style::Layer::Impl>>> layers;
     optional<std::unique_ptr<const GeometryTileData>> data;
-    optional<PlacementConfig> placementConfig;
 
     bool symbolLayoutsNeedPreparation = false;
     std::vector<std::unique_ptr<SymbolLayout>> symbolLayouts;
@@ -83,6 +84,8 @@ private:
     ImageDependencies pendingImageDependencies;
     GlyphMap glyphMap;
     ImageMap imageMap;
+    
+    bool showCollisionBoxes;
 };
 
 } // namespace mbgl