feat: add particle static CPU fast path

src/mbgl/renderer/renderer.cpp

@@ -24,6 +24,7 @@ Renderer::~Renderer() {
 }
 
 void Renderer::markContextLost() {
+    impl->clearPreparedRenderTree();
     impl->orchestrator.markContextLost();
 }
 
@@ -39,12 +40,21 @@ void Renderer::render(const std::shared_ptr<UpdateParameters>& updateParameters)
     const bool styleChanged = impl->styleLoaded && !updateParameters->styleLoaded;
     impl->styleLoaded = updateParameters->styleLoaded;
     if (!impl->dynamicTextureAtlas || styleChanged) {
+        if (styleChanged) impl->clearPreparedRenderTree();
         auto& context = impl->backend.getContext();
         impl->dynamicTextureAtlas = std::make_unique<gfx::DynamicTextureAtlas>(context);
     }
+    if (impl->tryRenderParticleFastFrame(updateParameters)) return;
+    // A full createRenderTree may replace RenderLayer/RenderSource instances.
+    // Drop the old prepared tree first so its reference-based render items can
+    // never outlive the orchestrator objects they describe.
+    impl->clearPreparedRenderTree();
     if (auto renderTree = impl->orchestrator.createRenderTree(updateParameters, impl->dynamicTextureAtlas)) {
         renderTree->prepare();
-        impl->render(*renderTree, updateParameters);
+        impl->render(*renderTree, updateParameters, false);
+        impl->commitPreparedRenderTree(std::move(renderTree), updateParameters);
+    } else {
+        impl->clearPreparedRenderTree();
     }
 }
 
@@ -162,11 +172,13 @@ bool Renderer::getTileCacheEnabled() const {
 
 void Renderer::reduceMemoryUse() {
     gfx::BackendScope guard{impl->backend};
+    impl->clearPreparedRenderTree();
     impl->reduceMemoryUse();
     impl->orchestrator.reduceMemoryUse();
 }
 
 void Renderer::clearData() {
+    impl->clearPreparedRenderTree();
     impl->orchestrator.clearData();
 }