Implement viewChanged() in multiple examples for proper window resize handling, fix triangle example resizing on macOS

examples/computeshader/computeshader.cpp

@@ -654,6 +654,12 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		camera.setPerspective(60.0f, (float)width * 0.5f / (float)height, 1.0f, 256.0f);
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/conditionalrender/conditionalrender.cpp

@@ -330,6 +330,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Visibility")) {

examples/debugmarker/debugmarker.cpp

@@ -777,6 +777,10 @@ public:
 			updateUniformBuffers();
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
 
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
@@ -796,4 +800,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/deferred/deferred.cpp

@@ -809,6 +809,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBufferOffscreen();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/deferredmultisampling/deferredmultisampling.cpp

@@ -647,6 +647,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBufferOffscreen();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/deferredshadows/deferredshadows.cpp

@@ -808,6 +808,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBufferOffscreen();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/descriptorindexing/descriptorindexing.cpp

@@ -409,6 +409,11 @@ public:
 			updateUniformBuffersCamera();
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffersCamera();
+	}
+
 };
 
 VULKAN_EXAMPLE_MAIN()

examples/displacement/displacement.cpp

@@ -385,6 +385,12 @@ public:
 			updateUniformBuffers();
 		}
 	}
+
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {
@@ -408,4 +414,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/distancefieldfonts/distancefieldfonts.cpp

@@ -643,6 +643,7 @@ public:
 
 	virtual void viewChanged()
 	{
+		camera.setPerspective(splitScreen ? 30.0f : 45.0f, (float)width / (float)(height * ((splitScreen) ? 0.5f : 1.0f)), 1.0f, 256.0f);
 		updateUniformBuffers();
 	}
 
@@ -663,4 +664,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/gltfloading/gltfloading.cpp

@@ -729,6 +729,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/gltfscenerendering/gltfscenerendering.cpp

@@ -631,6 +631,11 @@ void VulkanExample::render()
 	}
 }
 
+void VulkanExample::viewChanged()
+{
+	updateUniformBuffers();
+}
+
 void VulkanExample::OnUpdateUIOverlay(vks::UIOverlay* overlay)
 {
 	if (overlay->header("Visibility")) {
@@ -659,4 +664,4 @@ void VulkanExample::OnUpdateUIOverlay(vks::UIOverlay* overlay)
 	}
 }
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/gltfscenerendering/gltfscenerendering.h

@@ -162,5 +162,6 @@ public:
 	void updateUniformBuffers();
 	void prepare();
 	virtual void render();
+	virtual void viewChanged();
 	virtual void OnUpdateUIOverlay(vks::UIOverlay* overlay);
 };

examples/gltfskinning/gltfskinning.cpp

@@ -995,6 +995,11 @@ void VulkanExample::render()
 	}
 }
 
+void VulkanExample::viewChanged()
+{
+	updateUniformBuffers();
+}
+
 void VulkanExample::OnUpdateUIOverlay(vks::UIOverlay *overlay)
 {
 	if (overlay->header("Settings"))
@@ -1006,4 +1011,4 @@ void VulkanExample::OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	}
 }
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/gltfskinning/gltfskinning.h

@@ -232,5 +232,6 @@ class VulkanExample : public VulkanExampleBase
 	void         updateUniformBuffers();
 	void         prepare();
 	virtual void render();
+	virtual void viewChanged();
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay);
 };

examples/hdr/hdr.cpp

@@ -870,6 +870,11 @@ public:
 			updateUniformBuffers();
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/indirectdraw/indirectdraw.cpp

@@ -499,6 +499,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffer(true);
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (!vulkanDevice->features.multiDrawIndirect) {
@@ -512,4 +517,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/inlineuniformblocks/inlineuniformblocks.cpp

@@ -357,6 +357,11 @@ public:
 			updateUniformBuffers();
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	/*
 		[POI] Update descriptor sets at runtime
 	*/
@@ -401,4 +406,4 @@ public:
 
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/inputattachments/inputattachments.cpp

@@ -606,6 +606,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/instancing/instancing.cpp

@@ -482,6 +482,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffer(true);
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Statistics")) {
@@ -490,4 +495,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/multisampling/multisampling.cpp

@@ -541,6 +541,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	// Returns the maximum sample count usable by the platform
 	VkSampleCountFlagBits getMaxUsableSampleCount()
 	{

examples/multithreading/multithreading.cpp

@@ -527,6 +527,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateMatrices();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Statistics")) {
@@ -539,4 +544,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/multiview/multiview.cpp

@@ -738,6 +738,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/oit/oit.cpp

@@ -507,7 +507,7 @@ private:
 		vkUpdateDescriptorSets(device, static_cast<uint32_t>(writeDescriptorSets.size()), writeDescriptorSets.data(), 0, NULL);
 	}
 
-	void buildCommandBuffers()
+	void buildCommandBuffers() override
 	{
 		if (resized)
 			return;
@@ -656,4 +656,4 @@ private:
 	VkDeviceSize objectUniformBufferSize;
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/particlefire/particlefire.cpp

@@ -589,6 +589,11 @@ public:
 			updateUniformBuffers();
 		}
 	}
+
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/pbrtexture/pbrtexture.cpp

@@ -1340,6 +1340,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/pipelines/pipelines.cpp

@@ -334,6 +334,12 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		camera.setPerspective(60.0f, (float)(width / 3.0f) / (float)height, 0.1f, 256.0f);
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (!deviceFeatures.fillModeNonSolid) {
@@ -344,4 +350,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/pushdescriptors/pushdescriptors.cpp

@@ -337,6 +337,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/specializationconstants/specializationconstants.cpp

@@ -320,10 +320,10 @@ public:
 		}
 	}
 
-	virtual void windowResized()
+	virtual void viewChanged()
 	{
 		updateUniformBuffers();
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/sphericalenvmapping/sphericalenvmapping.cpp

@@ -277,6 +277,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {
@@ -288,4 +293,4 @@ public:
 
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/ssao/ssao.cpp

@@ -944,6 +944,12 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBufferMatrices();
+		updateUniformBufferSSAOParams();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/subpasses/subpasses.cpp

@@ -903,6 +903,12 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBufferDeferredMatrices();
+		updateUniformBufferDeferredLights();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Subpasses")) {

examples/terraintessellation/terraintessellation.cpp

@@ -828,6 +828,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {
@@ -853,4 +858,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/tessellation/tessellation.cpp

@@ -326,6 +326,12 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		camera.setPerspective(45.0f, (float)(width * ((splitScreen) ? 0.5f : 1.0f)) / (float)height, 0.1f, 256.0f);
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/textoverlay/textoverlay.cpp

@@ -514,6 +514,8 @@ public:
 			case alignCenter:
 				x -= textWidth / 2.0f;
 				break;
+			case alignLeft:
+				break;
 		}
 
 		// Generate a uv mapped quad per char in the new text
@@ -885,6 +887,10 @@ public:
 		if (!prepared)
 			return;
 		draw();
+		if (camera.updated)
+		{
+			updateUniformBuffers();
+		}
 		if (frameCounter == 0)
 		{
 			vkDeviceWaitIdle(device);
@@ -892,13 +898,6 @@ public:
 		}
 	}
 
-	virtual void viewChanged()
-	{
-		vkDeviceWaitIdle(device);
-		updateUniformBuffers();
-		updateTextOverlay();
-	}
-
 	virtual void windowResized()
 	{
 		// SRS - Recreate text overlay resources in case number of swapchain images has changed on resize
@@ -906,6 +905,12 @@ public:
 		prepareTextOverlay();
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+		updateTextOverlay();
+	}
+
 #if !defined(__ANDROID__)
 	virtual void keyPressed(uint32_t keyCode)
 	{

examples/texture3d/texture3d.cpp

@@ -773,6 +773,11 @@ public:
 			updateUniformBuffers(camera.updated);
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers(true);
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {

examples/texturearray/texturearray.cpp

@@ -550,6 +550,10 @@ public:
 			updateUniformBuffersCamera();
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffersCamera();
+	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/texturecubemaparray/texturecubemaparray.cpp

@@ -529,6 +529,11 @@ public:
 		}
 	}
 
+	virtual void viewChanged()
+	{
+		updateUniformBuffers();
+	}
+
 	virtual void OnUpdateUIOverlay(vks::UIOverlay *overlay)
 	{
 		if (overlay->header("Settings")) {
@@ -548,4 +553,4 @@ public:
 	}
 };
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/texturesparseresidency/texturesparseresidency.cpp

@@ -708,6 +708,11 @@ void VulkanExample::render()
 	}
 }
 
+void VulkanExample::viewChanged()
+{
+	updateUniformBuffers();
+}
+
 // Fills a buffer with random colors
 void VulkanExample::randomPattern(uint8_t* buffer, uint32_t width, uint32_t height)
 {

examples/texturesparseresidency/texturesparseresidency.h

@@ -116,6 +116,7 @@ public:
 	void updateUniformBuffers();
 	void prepare();
 	virtual void render();
+	virtual void viewChanged();
 	void uploadContent(VirtualTexturePage page, VkImage image);
 	void fillRandomPages();
 	void fillMipTail();

examples/triangle/triangle.cpp

@@ -109,7 +109,7 @@ public:
 
 	// Fences
 	// Used to check the completion of queue operations (e.g. command buffer execution)
-	std::vector<VkFence> waitFences;
+	std::vector<VkFence> queueCompleteFences;
 
 	VulkanExample() : VulkanExampleBase(ENABLE_VALIDATION)
 	{
@@ -148,7 +148,7 @@ public:
 		vkDestroySemaphore(device, presentCompleteSemaphore, nullptr);
 		vkDestroySemaphore(device, renderCompleteSemaphore, nullptr);
 
-		for (auto& fence : waitFences)
+		for (auto& fence : queueCompleteFences)
 		{
 			vkDestroyFence(device, fence, nullptr);
 		}
@@ -196,8 +196,8 @@ public:
 		fenceCreateInfo.sType = VK_STRUCTURE_TYPE_FENCE_CREATE_INFO;
 		// Create in signaled state so we don't wait on first render of each command buffer
 		fenceCreateInfo.flags = VK_FENCE_CREATE_SIGNALED_BIT;
-		waitFences.resize(drawCmdBuffers.size());
-		for (auto& fence : waitFences)
+		queueCompleteFences.resize(drawCmdBuffers.size());
+		for (auto& fence : queueCompleteFences)
 		{
 			VK_CHECK_RESULT(vkCreateFence(device, &fenceCreateInfo, nullptr, &fence));
 		}
@@ -337,6 +337,16 @@ public:
 
 	void draw()
 	{
+#if defined(VK_USE_PLATFORM_MACOS_MVK)
+		// SRS - on macOS use swapchain helper function with common semaphores/fences for proper resize handling
+		// Get next image in the swap chain (back/front buffer)
+		prepareFrame();
+
+		// Use a fence to wait until the command buffer has finished execution before using it again
+		VK_CHECK_RESULT(vkWaitForFences(device, 1, &waitFences[currentBuffer], VK_TRUE, UINT64_MAX));
+		VK_CHECK_RESULT(vkResetFences(device, 1, &waitFences[currentBuffer]));
+#else
+		// SRS - on other platforms use original bare code with local semaphores/fences for illustrative purposes
 		// Get next image in the swap chain (back/front buffer)
 		VkResult acquire = swapChain.acquireNextImage(presentCompleteSemaphore, &currentBuffer);
 		if (!((acquire == VK_SUCCESS) || (acquire == VK_SUBOPTIMAL_KHR))) {
@@ -344,8 +354,9 @@ public:
 		}
 
 		// Use a fence to wait until the command buffer has finished execution before using it again
-		VK_CHECK_RESULT(vkWaitForFences(device, 1, &waitFences[currentBuffer], VK_TRUE, UINT64_MAX));
-		VK_CHECK_RESULT(vkResetFences(device, 1, &waitFences[currentBuffer]));
+		VK_CHECK_RESULT(vkWaitForFences(device, 1, &queueCompleteFences[currentBuffer], VK_TRUE, UINT64_MAX));
+		VK_CHECK_RESULT(vkResetFences(device, 1, &queueCompleteFences[currentBuffer]));
+#endif
 
 		// Pipeline stage at which the queue submission will wait (via pWaitSemaphores)
 		VkPipelineStageFlags waitStageMask = VK_PIPELINE_STAGE_COLOR_ATTACHMENT_OUTPUT_BIT;
@@ -353,16 +364,29 @@ public:
 		VkSubmitInfo submitInfo = {};
 		submitInfo.sType = VK_STRUCTURE_TYPE_SUBMIT_INFO;
 		submitInfo.pWaitDstStageMask = &waitStageMask;               // Pointer to the list of pipeline stages that the semaphore waits will occur at
-		submitInfo.pWaitSemaphores = &presentCompleteSemaphore;      // Semaphore(s) to wait upon before the submitted command buffer starts executing
 		submitInfo.waitSemaphoreCount = 1;                           // One wait semaphore
-		submitInfo.pSignalSemaphores = &renderCompleteSemaphore;     // Semaphore(s) to be signaled when command buffers have completed
 		submitInfo.signalSemaphoreCount = 1;                         // One signal semaphore
 		submitInfo.pCommandBuffers = &drawCmdBuffers[currentBuffer]; // Command buffers(s) to execute in this batch (submission)
 		submitInfo.commandBufferCount = 1;                           // One command buffer
 
+#if defined(VK_USE_PLATFORM_MACOS_MVK)
+		// SRS - on macOS use swapchain helper function with common semaphores/fences for proper resize handling
+		submitInfo.pWaitSemaphores = &semaphores.presentComplete;    // Semaphore(s) to wait upon before the submitted command buffer starts executing
+		submitInfo.pSignalSemaphores = &semaphores.renderComplete;   // Semaphore(s) to be signaled when command buffers have completed
+
 		// Submit to the graphics queue passing a wait fence
 		VK_CHECK_RESULT(vkQueueSubmit(queue, 1, &submitInfo, waitFences[currentBuffer]));
 
+		// Present the current buffer to the swap chain
+		submitFrame();
+#else
+		// SRS - on other platforms use original bare code with local semaphores/fences for illustrative purposes
+		submitInfo.pWaitSemaphores = &presentCompleteSemaphore;      // Semaphore(s) to wait upon before the submitted command buffer starts executing
+		submitInfo.pSignalSemaphores = &renderCompleteSemaphore;     // Semaphore(s) to be signaled when command buffers have completed
+
+		// Submit to the graphics queue passing a wait fence
+		VK_CHECK_RESULT(vkQueueSubmit(queue, 1, &submitInfo, queueCompleteFences[currentBuffer]));
+
 		// Present the current buffer to the swap chain
 		// Pass the semaphore signaled by the command buffer submission from the submit info as the wait semaphore for swap chain presentation
 		// This ensures that the image is not presented to the windowing system until all commands have been submitted
@@ -370,7 +394,7 @@ public:
 		if (!((present == VK_SUCCESS) || (present == VK_SUBOPTIMAL_KHR))) {
 			VK_CHECK_RESULT(present);
 		}
-
+#endif
 	}
 
 	// Prepare vertex and index buffers for an indexed triangle
@@ -1235,7 +1259,7 @@ int main(const int argc, const char *argv[])
 		vulkanExample->setupWindow(nullptr);
 		vulkanExample->prepare();
 		vulkanExample->renderLoop();
-		delete(vulkanExample);
+		//delete(vulkanExample);		// SRS - vulkanExample deleted by AppDelegate termination event handler
 	}
 	return 0;
 }

examples/vertexattributes/vertexattributes.cpp

@@ -580,6 +580,11 @@ void VulkanExample::render()
 	}
 }
 
+void VulkanExample::viewChanged()
+{
+	updateUniformBuffers();
+}
+
 void VulkanExample::OnUpdateUIOverlay(vks::UIOverlay* overlay)
 {
 	if (overlay->header("Vertex buffer attributes")) {
@@ -596,4 +601,4 @@ void VulkanExample::OnUpdateUIOverlay(vks::UIOverlay* overlay)
 	}
 }
 
-VULKAN_EXAMPLE_MAIN()
+VULKAN_EXAMPLE_MAIN()

examples/vertexattributes/vertexattributes.h

@@ -139,5 +139,6 @@ public:
 	void loadSceneNode(const tinygltf::Node& inputNode, const tinygltf::Model& input, Node* parent);
 	void drawSceneNode(VkCommandBuffer commandBuffer, Node node);
 	virtual void render();
+	virtual void viewChanged();
 	virtual void OnUpdateUIOverlay(vks::UIOverlay* overlay);
 };