[core] Calculate GeoJSON tile geometries in a background thread

Call `mapbox::geojsonvt::GeoJSONVT::getTile()` in a background
thread, so that the rendering thread is not blocked.

1 files changed, 3 insertions, 4 deletions

diff --git a/src/mbgl/renderer/sources/render_geojson_source.cpp b/src/mbgl/renderer/sources/render_geojson_source.cpp
index 4ed9dd9334..94d171cf18 100644
--- a/src/mbgl/renderer/sources/render_geojson_source.cpp
+++ b/src/mbgl/renderer/sources/render_geojson_source.cpp
@@ -95,8 +95,7 @@ void RenderGeoJSONSource::update(Immutable<style::Source::Impl> baseImpl_,
             const uint8_t maxZ = impl().getZoomRange().max;
             for (const auto& pair : tilePyramid.getTiles()) {
                 if (pair.first.canonical.z <= maxZ) {
-                    static_cast<GeoJSONTile*>(pair.second.get())
-                        ->updateData(data_->getTile(pair.first.canonical), needsRelayout);
+                    static_cast<GeoJSONTile*>(pair.second.get())->updateData(data_, needsRelayout);
                 }
             }
         }
@@ -112,8 +111,8 @@ void RenderGeoJSONSource::update(Immutable<style::Source::Impl> baseImpl_,
                        util::tileSize,
                        impl().getZoomRange(),
                        optional<LatLngBounds>{},
-                       [&, data_] (const OverscaledTileID& tileID) {
-                           return std::make_unique<GeoJSONTile>(tileID, impl().id, parameters, data_->getTile(tileID.canonical));
+                       [&, data_](const OverscaledTileID& tileID) {
+                           return std::make_unique<GeoJSONTile>(tileID, impl().id, parameters, data_);
                        });
 }