re organisation

apps/LoopThroughWithOpenGLCompositing/gl/pipeline/TemporalHistoryBuffers.h

@@ -0,0 +1,51 @@
+#pragma once
+
+#include "GLExtensions.h"
+#include "ShaderTypes.h"
+
+#include <windows.h>
+
+#include <gl/gl.h>
+#include <map>
+#include <string>
+#include <vector>
+
+struct RuntimeRenderState;
+
+class TemporalHistoryBuffers
+{
+public:
+	struct Slot
+	{
+		GLuint texture = 0;
+		GLuint framebuffer = 0;
+	};
+
+	struct Ring
+	{
+		std::vector<Slot> slots;
+		std::size_t nextWriteIndex = 0;
+		std::size_t filledCount = 0;
+		unsigned effectiveLength = 0;
+		TemporalHistorySource historySource = TemporalHistorySource::None;
+	};
+
+	bool ValidateTextureUnitBudget(const std::vector<RuntimeRenderState>& layerStates, unsigned historyCap, std::string& error) const;
+	bool EnsureResources(const std::vector<RuntimeRenderState>& layerStates, unsigned historyCap, unsigned frameWidth, unsigned frameHeight, std::string& error);
+	bool CreateRing(Ring& ring, unsigned effectiveLength, TemporalHistorySource historySource, unsigned frameWidth, unsigned frameHeight, std::string& error);
+	void DestroyRing(Ring& ring);
+	void DestroyResources();
+	void ResetState();
+	void PushFramebuffer(GLuint sourceFramebuffer, Ring& ring, unsigned frameWidth, unsigned frameHeight);
+	void PushSourceFramebuffer(GLuint sourceFramebuffer, unsigned frameWidth, unsigned frameHeight);
+	void PushPreLayerFramebuffer(const std::string& layerId, GLuint sourceFramebuffer, unsigned frameWidth, unsigned frameHeight);
+	void BindSamplers(const RuntimeRenderState& state, GLuint currentSourceTexture, unsigned historyCap);
+	GLuint ResolveTexture(const Ring& ring, GLuint fallbackTexture, std::size_t framesAgo) const;
+	unsigned SourceAvailableCount() const;
+	unsigned AvailableCountForLayer(const std::string& layerId) const;
+
+private:
+	Ring sourceHistoryRing;
+	std::map<std::string, Ring> preLayerHistoryByLayerId;
+	bool mNeedsReset = true;
+};