[core] make symbols fade out faster while zooming out

Zooming outcan make symbols overlap quickly. The area previously covered
by the viewport is covered by a lot of colliding labels while the
surrounding area has no labels. This difference produces an unwanted
effect.

This reduces that effect by:
- reducing the fade duration while zooming out
- doing placement more frequently while zooming out

1 files changed, 2 insertions, 2 deletions

diff --git a/src/mbgl/renderer/render_orchestrator.cpp b/src/mbgl/renderer/render_orchestrator.cpp
index 5b6b27c185..f9956dbc2a 100644
--- a/src/mbgl/renderer/render_orchestrator.cpp
+++ b/src/mbgl/renderer/render_orchestrator.cpp
@@ -361,7 +361,7 @@ std::unique_ptr<RenderTree> RenderOrchestrator::createRenderTree(const UpdatePar
         }
 
         bool symbolBucketsChanged = false;
-        const bool placementChanged = !placement->stillRecent(updateParameters.timePoint);
+        const bool placementChanged = !placement->stillRecent(updateParameters.timePoint, updateParameters.transformState.getZoom());
         std::set<std::string> usedSymbolLayers;
         if (placementChanged) {
             placement = std::make_unique<Placement>(
@@ -381,7 +381,7 @@ std::unique_ptr<RenderTree> RenderOrchestrator::createRenderTree(const UpdatePar
         }
 
         if (placementChanged) {
-            placement->commit(updateParameters.timePoint);
+            placement->commit(updateParameters.timePoint, updateParameters.transformState.getZoom());
             crossTileSymbolIndex.pruneUnusedLayers(usedSymbolLayers);
             for (const auto& entry : renderSources) {
                 entry.second->updateFadingTiles();