add onStyleImageMissing to allow dynamically loaded or generated images (#14253)

Also make `Style#updateImage(...)` much faster when the image doesn't change size. This can be useful for asynchronously generating images.

3 files changed, 19 insertions, 3 deletions

diff --git a/platform/darwin/src/MGLRendererFrontend.h b/platform/darwin/src/MGLRendererFrontend.h
index 2df67ca4e4..c0e03351c6 100644
--- a/platform/darwin/src/MGLRendererFrontend.h
+++ b/platform/darwin/src/MGLRendererFrontend.h
@@ -49,7 +49,12 @@ public:
         
         mbgl::BackendScope guard { mbglBackend, mbgl::BackendScope::ScopeType::Implicit };
         
-        renderer->render(*updateParameters);
+        // onStyleImageMissing might be called during a render. The user implemented method
+        // could trigger a call to MGLRenderFrontend#update which overwrites `updateParameters`.
+        // Copy the shared pointer here so that the parameters aren't destroyed while `render(...)` is
+        // still using them.
+        auto updateParameters_ = updateParameters;
+        renderer->render(*updateParameters_);
     }
     
     mbgl::Renderer* getRenderer() {
diff --git a/platform/default/src/mbgl/gl/headless_frontend.cpp b/platform/default/src/mbgl/gl/headless_frontend.cpp
index f3dae2dbc9..c311e2df41 100644
--- a/platform/default/src/mbgl/gl/headless_frontend.cpp
+++ b/platform/default/src/mbgl/gl/headless_frontend.cpp
@@ -20,7 +20,13 @@ HeadlessFrontend::HeadlessFrontend(Size size_, float pixelRatio_, Scheduler& sch
     asyncInvalidate([this] {
         if (renderer && updateParameters) {
             mbgl::BackendScope guard { backend };
-            renderer->render(*updateParameters);
+
+            // onStyleImageMissing might be called during a render. The user implemented method
+            // could trigger a call to MGLRenderFrontend#update which overwrites `updateParameters`.
+            // Copy the shared pointer here so that the parameters aren't destroyed while `render(...)` is
+            // still using them.
+            auto updateParameters_ = updateParameters;
+            renderer->render(*updateParameters_);
         }
     }),
     renderer(std::make_unique<Renderer>(backend, pixelRatio, scheduler, mode, programCacheDir, localFontFamily)) {
diff --git a/platform/glfw/glfw_renderer_frontend.cpp b/platform/glfw/glfw_renderer_frontend.cpp
index 73205f1c56..9c5320cc78 100644
--- a/platform/glfw/glfw_renderer_frontend.cpp
+++ b/platform/glfw/glfw_renderer_frontend.cpp
@@ -32,7 +32,12 @@ void GLFWRendererFrontend::render() {
     
     mbgl::BackendScope guard { glfwView, mbgl::BackendScope::ScopeType::Implicit };
 
-    renderer->render(*updateParameters);
+    // onStyleImageMissing might be called during a render. The user implemented method
+    // could trigger a call to MGLRenderFrontend#update which overwrites `updateParameters`.
+    // Copy the shared pointer here so that the parameters aren't destroyed while `render(...)` is
+    // still using them.
+    auto updateParameters_ = updateParameters;
+    renderer->render(*updateParameters_);
 }
 
 mbgl::Renderer* GLFWRendererFrontend::getRenderer() {