Viewport, Platform: Refactored platform interface. Removed need to use imgui_internal.h in backends. Split viewport into public facing ImGuiViewport and internal structure. Exposing enough data to provide custom tweaked renderers. Renamed handlers, fixed lots of inconsistencies. (#1542, #1042)

examples/vulkan_example/main.cpp

@@ -478,7 +478,11 @@ int main(int, char**)
         ImGui::Render();
         memcpy(&wd->ClearValue.color.float32[0], &clear_color, 4 * sizeof(float));
 		FrameRender(wd);
-		ImGui::RenderAdditionalViewports();
+
+        // Update and Render additional Platform Windows
+        ImGui::UpdatePlatformWindows();
+        ImGui::RenderPlatformWindows();
+
         FramePresent(wd);
     }