[glfw] add animated annotations to glfw app for debugging

platform/glfw/glfw_view.cpp

@@ -288,6 +288,7 @@ void GLFWView::onKey(GLFWwindow *window, int key, int /*scancode*/, int action,
         case GLFW_KEY_8: view->addRandomShapeAnnotations(10); break;
         case GLFW_KEY_9: view->addRandomShapeAnnotations(100); break;
         case GLFW_KEY_0: view->addRandomShapeAnnotations(1000); break;
+        case GLFW_KEY_M: view->addAnimatedAnnotation(); break;
         }
     }
 }
@@ -379,12 +380,36 @@ void GLFWView::addRandomShapeAnnotations(int count) {
     }
 }
 
+void GLFWView::addAnimatedAnnotation() {
+    const double started = glfwGetTime();
+    animatedAnnotationIDs.push_back(map->addAnnotation(mbgl::SymbolAnnotation { { 0, 0 } , "default_marker" }));
+    animatedAnnotationAddedTimes.push_back(started);
+}
+
+void GLFWView::updateAnimatedAnnotations() {
+    const double time = glfwGetTime();
+    for (size_t i = 0; i < animatedAnnotationIDs.size(); i++) {
+        auto dt = time - animatedAnnotationAddedTimes[i];
+
+        const double period = 10;
+        const double x = dt / period * 360 - 180;
+        const double y = std::sin(dt/ period * M_PI * 2.0) * 80;
+        map->updateAnnotation(animatedAnnotationIDs[i], mbgl::SymbolAnnotation { {x, y }, "default_marker" });
+    }
+}
+
 void GLFWView::clearAnnotations() {
     for (const auto& id : annotationIDs) {
         map->removeAnnotation(id);
     }
 
     annotationIDs.clear();
+
+    for (const auto& id : animatedAnnotationIDs) {
+        map->removeAnnotation(id);
+    }
+
+    animatedAnnotationIDs.clear();
 }
 
 void GLFWView::popAnnotation() {
@@ -506,6 +531,8 @@ void GLFWView::run() {
             if (animateRouteCallback)
                 animateRouteCallback(map);
 
+            updateAnimatedAnnotations();
+
             activate();
 
             rendererFrontend->render();

platform/glfw/glfw_view.hpp

@@ -78,13 +78,18 @@ class GLFWView : public mbgl::RendererBackend, public mbgl::MapObserver {
     void addRandomLineAnnotations(int count);
     void addRandomShapeAnnotations(int count);
     void addRandomCustomPointAnnotations(int count);
+    void addAnimatedAnnotation();
+    void updateAnimatedAnnotations();
 
     void clearAnnotations();
     void popAnnotation();
 
     mbgl::AnnotationIDs annotationIDs;
     std::vector<std::string> spriteIDs;
 
+    mbgl::AnnotationIDs animatedAnnotationIDs;
+    std::vector<double> animatedAnnotationAddedTimes;
+
 private:
     void toggle3DExtrusions(bool visible);