Because a message we queue from the foreground may cause the background to complete, exit, and tear down the AsyncTask, we have to block queue processing until we've finished our call to AsyncTask::send().
Broadening the scope of a mutex is scary, but I audited the code of our four implementations of AsyncTask and I don't see any way this could cause a deadlock.
Don't mark items that are outside the collision grid range as placed.
Requires new ignore because GL JS issue #5654 allows insertion of symbols outside the CollisionIndex range, and those symbols can cascade in to affect items within the viewport.
- 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.
- Switches from tile to viewport coordinates
- Represents line labels with circle geometries
- Projects line labels at collision detection time to improve accuracy
- Adapts tile-based symbol queries to viewport coordinates
- Adds early exiting "hitTest" query for fast collision detection
- GridIndex now determines cell count separately for x and y axes based on grid dimensions.
This class is responsible for tracking which symbols are "the same" between tiles at different zoom levels, so that symbol opacities (fade animations) can be copied smoothly between tiles.
