PNG writer

apps/LoopThroughWithOpenGLCompositing/gl/OpenGLComposite.h

@@ -18,6 +18,7 @@
 
 #include <functional>
 #include <atomic>
+#include <filesystem>
 #include <map>
 #include <memory>
 #include <string>
@@ -54,6 +55,7 @@ public:
 	bool ResetLayerParameters(const std::string& layerId, std::string& error);
 	bool SaveStackPreset(const std::string& presetName, std::string& error);
 	bool LoadStackPreset(const std::string& presetName, std::string& error);
+	bool RequestScreenshot(std::string& error);
 	unsigned short GetControlServerPort() const;
 	unsigned short GetOscPort() const;
 	std::string GetControlUrl() const;
@@ -87,11 +89,14 @@ private:
 	std::unique_ptr<RuntimeServices>		mRuntimeServices;
 	std::vector<RuntimeRenderState>			mCachedLayerRenderStates;
 	std::atomic<bool>						mUseCommittedLayerStates;
+	std::atomic<bool>						mScreenshotRequested;
 
 	bool InitOpenGLState();
 	void renderEffect();
 	bool ProcessRuntimePollResults();
 	void RequestShaderBuild();
+	void ProcessScreenshotRequest();
+	std::filesystem::path BuildScreenshotPath() const;
 	void broadcastRuntimeState();
 	void resetTemporalHistoryState();
 };