raze/source/common/rendering/hwrenderer/postprocessing/hw_postprocess.h

#pragma once

#include "hwrenderer/data/shaderuniforms.h"
#include <memory>
#include <map>

struct PostProcessShader;

typedef FRenderStyle PPBlendMode;
typedef IntRect PPViewport;

class PPTexture;
class PPShader;

enum class PPFilterMode { Nearest, Linear };
enum class PPWrapMode { Clamp, Repeat };
enum class PPTextureType { CurrentPipelineTexture, NextPipelineTexture, PPTexture, SceneColor, SceneFog, SceneNormal, SceneDepth, SwapChain, ShadowMap };

class PPTextureInput
{
public:
	PPFilterMode Filter = PPFilterMode::Nearest;
	PPWrapMode Wrap = PPWrapMode::Clamp;
	PPTextureType Type = PPTextureType::CurrentPipelineTexture;
	PPTexture *Texture = nullptr;
};

class PPOutput
{
public:
	PPTextureType Type = PPTextureType::NextPipelineTexture;
	PPTexture *Texture = nullptr;
};

class PPUniforms
{
public:
	PPUniforms()
	{
	}

	PPUniforms(const PPUniforms &src)
	{
		Data = src.Data;
	}

	~PPUniforms()
	{
		Clear();
	}

	PPUniforms &operator=(const PPUniforms &src)
	{
		Data = src.Data;
		return *this;
	}

	void Clear()
	{
		Data.Clear();
	}

	template<typename T>
	void Set(const T &v)
	{
		if (Data.Size() != (int)sizeof(T))
		{
			Data.Resize(sizeof(T));
			memcpy(Data.Data(), &v, Data.Size());
		}
	}

	TArray<uint8_t> Data;
};

class PPRenderState
{
public:
	virtual ~PPRenderState() = default;

	virtual void PushGroup(const FString &name) = 0;
	virtual void PopGroup() = 0;

	virtual void Draw() = 0;

	void Clear()
	{
		Shader = nullptr;
		Textures = TArray<PPTextureInput>();
		Uniforms = PPUniforms();
		Viewport = PPViewport();
		BlendMode = PPBlendMode();
		Output = PPOutput();
		ShadowMapBuffers = false;
	}

	void SetInputTexture(int index, PPTexture *texture, PPFilterMode filter = PPFilterMode::Nearest, PPWrapMode wrap = PPWrapMode::Clamp)
	{
		if ((int)Textures.Size() < index + 1)
			Textures.Resize(index + 1);
		auto &tex = Textures[index];
		tex.Filter = filter;
		tex.Wrap = wrap;
		tex.Type = PPTextureType::PPTexture;
		tex.Texture = texture;
	}

	void SetInputCurrent(int index, PPFilterMode filter = PPFilterMode::Nearest, PPWrapMode wrap = PPWrapMode::Clamp)
	{
		SetInputSpecialType(index, PPTextureType::CurrentPipelineTexture, filter, wrap);
	}

	void SetInputSceneColor(int index, PPFilterMode filter = PPFilterMode::Nearest, PPWrapMode wrap = PPWrapMode::Clamp)
	{
		SetInputSpecialType(index, PPTextureType::SceneColor, filter, wrap);
	}

	void SetInputSceneFog(int index, PPFilterMode filter = PPFilterMode::Nearest, PPWrapMode wrap = PPWrapMode::Clamp)
	{
		SetInputSpecialType(index, PPTextureType::SceneFog, filter, wrap);
	}

	void SetInputSceneNormal(int index, PPFilterMode filter = PPFilterMode::Nearest, PPWrapMode wrap = PPWrapMode::Clamp)
	{
		SetInputSpecialType(index, PPTextureType::SceneNormal, filter, wrap);
	}

	void SetInputSceneDepth(int index, PPFilterMode filter = PPFilterMode::Nearest, PPWrapMode wrap = PPWrapMode::Clamp)
	{
		SetInputSpecialType(index, PPTextureType::SceneDepth, filter, wrap);
	}

	void SetInputSpecialType(int index, PPTextureType type, PPFilterMode filter = PPFilterMode::Nearest, PPWrapMode wrap = PPWrapMode::Clamp)
	{
		if ((int)Textures.Size() < index + 1)
			Textures.Resize(index + 1);
		auto &tex = Textures[index];
		tex.Filter = filter;
		tex.Wrap = wrap;
		tex.Type = type;
		tex.Texture = nullptr;
	}

	void SetShadowMapBuffers(bool enable)
	{
		ShadowMapBuffers = enable;
	}

	void SetOutputTexture(PPTexture *texture)
	{
		Output.Type = PPTextureType::PPTexture;
		Output.Texture = texture;
	}

	void SetOutputCurrent()
	{
		Output.Type = PPTextureType::CurrentPipelineTexture;
		Output.Texture = nullptr;
	}

	void SetOutputNext()
	{
		Output.Type = PPTextureType::NextPipelineTexture;
		Output.Texture = nullptr;
	}

	void SetOutputSceneColor()
	{
		Output.Type = PPTextureType::SceneColor;
		Output.Texture = nullptr;
	}

	void SetOutputSwapChain()
	{
		Output.Type = PPTextureType::SwapChain;
		Output.Texture = nullptr;
	}

	void SetOutputShadowMap()
	{
		Output.Type = PPTextureType::ShadowMap;
		Output.Texture = nullptr;
	}

	void SetNoBlend()
	{
		BlendMode.BlendOp = STYLEOP_Add;
		BlendMode.SrcAlpha = STYLEALPHA_One;
		BlendMode.DestAlpha = STYLEALPHA_Zero;
		BlendMode.Flags = 0;
	}

	void SetAdditiveBlend()
	{
		BlendMode.BlendOp = STYLEOP_Add;
		BlendMode.SrcAlpha = STYLEALPHA_One;
		BlendMode.DestAlpha = STYLEALPHA_One;
		BlendMode.Flags = 0;
	}

	void SetAlphaBlend()
	{
		BlendMode.BlendOp = STYLEOP_Add;
		BlendMode.SrcAlpha = STYLEALPHA_Src;
		BlendMode.DestAlpha = STYLEALPHA_InvSrc;
		BlendMode.Flags = 0;
	}

	PPShader *Shader;
	TArray<PPTextureInput> Textures;
	PPUniforms Uniforms;
	PPViewport Viewport;
	PPBlendMode BlendMode;
	PPOutput Output;
	bool ShadowMapBuffers = false;
};

enum class PixelFormat
{
	Rgba8,
	Rgba16f,
	R32f,
	Rg16f,
	Rgba16_snorm
};

class PPResource
{
public:
	PPResource()
	{
		Next = First;
		First = this;
		if (Next) Next->Prev = this;
	}

	PPResource(const PPResource &)
	{
		Next = First;
		First = this;
		if (Next) Next->Prev = this;
	}

	virtual ~PPResource()
	{
		if (Next) Next->Prev = Prev;
		if (Prev) Prev->Next = Next;
		else First = Next;
	}

	PPResource &operator=(const PPResource &other)
	{
		return *this;
	}

	static void ResetAll()
	{
		for (PPResource *cur = First; cur; cur = cur->Next)
			cur->ResetBackend();
	}

	virtual void ResetBackend() = 0;

private:
	static PPResource *First;
	PPResource *Prev = nullptr;
	PPResource *Next = nullptr;
};

class PPTextureBackend
{
public:
	virtual ~PPTextureBackend() = default;
};

class PPTexture : public PPResource
{
public:
	PPTexture() = default;
	PPTexture(int width, int height, PixelFormat format, std::shared_ptr<void> data = {}) : Width(width), Height(height), Format(format), Data(data) { }

	void ResetBackend() override { Backend.reset(); }

	int Width;
	int Height;
	PixelFormat Format;
	std::shared_ptr<void> Data;

	std::unique_ptr<PPTextureBackend> Backend;
};

class PPShaderBackend
{
public:
	virtual ~PPShaderBackend() = default;
};

class PPShader : public PPResource
{
public:
	PPShader() = default;
	PPShader(const FString &fragment, const FString &defines, const std::vector<UniformFieldDesc> &uniforms, int version = 330) : FragmentShader(fragment), Defines(defines), Uniforms(uniforms), Version(version) { }

	void ResetBackend() override { Backend.reset(); }

	FString VertexShader = "engine/shaders/pp/screenquad.vp";
	FString FragmentShader;
	FString Defines;
	std::vector<UniformFieldDesc> Uniforms;
	int Version = 330;

	std::unique_ptr<PPShaderBackend> Backend;
};

/////////////////////////////////////////////////////////////////////////////

struct ExtractUniforms
{
	FVector2 Scale;
	FVector2 Offset;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "Scale", UniformType::Vec2, offsetof(ExtractUniforms, Scale) },
			{ "Offset", UniformType::Vec2, offsetof(ExtractUniforms, Offset) }
		};
	}
};

struct BlurUniforms
{
	float SampleWeights[8];

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "SampleWeights0", UniformType::Float, offsetof(BlurUniforms, SampleWeights[0]) },
			{ "SampleWeights1", UniformType::Float, offsetof(BlurUniforms, SampleWeights[1]) },
			{ "SampleWeights2", UniformType::Float, offsetof(BlurUniforms, SampleWeights[2]) },
			{ "SampleWeights3", UniformType::Float, offsetof(BlurUniforms, SampleWeights[3]) },
			{ "SampleWeights4", UniformType::Float, offsetof(BlurUniforms, SampleWeights[4]) },
			{ "SampleWeights5", UniformType::Float, offsetof(BlurUniforms, SampleWeights[5]) },
			{ "SampleWeights6", UniformType::Float, offsetof(BlurUniforms, SampleWeights[6]) },
			{ "SampleWeights7", UniformType::Float, offsetof(BlurUniforms, SampleWeights[7]) },
		};
	}
};

enum { NumBloomLevels = 4 };

class PPBlurLevel
{
public:
	PPViewport Viewport;
	PPTexture VTexture;
	PPTexture HTexture;
};

class PPBloom
{
public:
	void RenderBloom(PPRenderState *renderstate, int sceneWidth, int sceneHeight, int fixedcm);
	void RenderBlur(PPRenderState *renderstate, int sceneWidth, int sceneHeight, float gameinfobluramount);

private:
	void BlurStep(PPRenderState *renderstate, const BlurUniforms &blurUniforms, PPTexture &input, PPTexture &output, PPViewport viewport, bool vertical);
	void UpdateTextures(int width, int height);

	static float ComputeBlurGaussian(float n, float theta);
	static void ComputeBlurSamples(int sampleCount, float blurAmount, float *sampleWeights);

	PPBlurLevel levels[NumBloomLevels];
	int lastWidth = 0;
	int lastHeight = 0;

	PPShader BloomCombine = { "engine/shaders/pp/bloomcombine.fp", "", {} };
	PPShader BloomExtract = { "engine/shaders/pp/bloomextract.fp", "", ExtractUniforms::Desc() };
	PPShader BlurVertical = { "engine/shaders/pp/blur.fp", "#define BLUR_VERTICAL\n", BlurUniforms::Desc() };
	PPShader BlurHorizontal = { "engine/shaders/pp/blur.fp", "#define BLUR_HORIZONTAL\n", BlurUniforms::Desc() };
};

/////////////////////////////////////////////////////////////////////////////

struct LensUniforms
{
	float AspectRatio;
	float Scale;
	float Padding0, Padding1;
	FVector4 LensDistortionCoefficient;
	FVector4 CubicDistortionValue;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "Aspect", UniformType::Float, offsetof(LensUniforms, AspectRatio) },
			{ "Scale", UniformType::Float, offsetof(LensUniforms, Scale) },
			{ "Padding0", UniformType::Float, offsetof(LensUniforms, Padding0) },
			{ "Padding1", UniformType::Float, offsetof(LensUniforms, Padding1) },
			{ "k", UniformType::Vec4, offsetof(LensUniforms, LensDistortionCoefficient) },
			{ "kcube", UniformType::Vec4, offsetof(LensUniforms, CubicDistortionValue) }
		};
	}
};

class PPLensDistort
{
public:
	void Render(PPRenderState *renderstate);

private:
	PPShader Lens = { "engine/shaders/pp/lensdistortion.fp", "", LensUniforms::Desc() };
};

/////////////////////////////////////////////////////////////////////////////

struct FXAAUniforms
{
	FVector2 ReciprocalResolution;
	float Padding0, Padding1;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "ReciprocalResolution", UniformType::Vec2, offsetof(FXAAUniforms, ReciprocalResolution) },
			{ "Padding0", UniformType::Float, offsetof(FXAAUniforms, Padding0) },
			{ "Padding1", UniformType::Float, offsetof(FXAAUniforms, Padding1) }
		};
	}
};

class PPFXAA
{
public:
	void Render(PPRenderState *renderstate);

private:
	void CreateShaders();
	int GetMaxVersion();
	FString GetDefines();

	PPShader FXAALuma;
	PPShader FXAA;
	int LastQuality = -1;
};

/////////////////////////////////////////////////////////////////////////////

struct ExposureExtractUniforms
{
	FVector2 Scale;
	FVector2 Offset;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "Scale", UniformType::Vec2, offsetof(ExposureExtractUniforms, Scale) },
			{ "Offset", UniformType::Vec2, offsetof(ExposureExtractUniforms, Offset) }
		};
	}
};

struct ExposureCombineUniforms
{
	float ExposureBase;
	float ExposureMin;
	float ExposureScale;
	float ExposureSpeed;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "ExposureBase", UniformType::Float, offsetof(ExposureCombineUniforms, ExposureBase) },
			{ "ExposureMin", UniformType::Float, offsetof(ExposureCombineUniforms, ExposureMin) },
			{ "ExposureScale", UniformType::Float, offsetof(ExposureCombineUniforms, ExposureScale) },
			{ "ExposureSpeed", UniformType::Float, offsetof(ExposureCombineUniforms, ExposureSpeed) }
		};
	}
};

class PPExposureLevel
{
public:
	PPViewport Viewport;
	PPTexture Texture;
};

class PPCameraExposure
{
public:
	void Render(PPRenderState *renderstate, int sceneWidth, int sceneHeight);

	PPTexture CameraTexture = { 1, 1, PixelFormat::R32f };

private:
	void UpdateTextures(int width, int height);

	std::vector<PPExposureLevel> ExposureLevels;
	bool FirstExposureFrame = true;

	PPShader ExposureExtract = { "engine/shaders/pp/exposureextract.fp", "", ExposureExtractUniforms::Desc() };
	PPShader ExposureAverage = { "engine/shaders/pp/exposureaverage.fp", "", {}, 400 };
	PPShader ExposureCombine = { "engine/shaders/pp/exposurecombine.fp", "", ExposureCombineUniforms::Desc() };
};

/////////////////////////////////////////////////////////////////////////////

struct ColormapUniforms
{
	FVector4 MapStart;
	FVector4 MapRange;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "uFixedColormapStart", UniformType::Vec4, offsetof(ColormapUniforms, MapStart) },
			{ "uFixedColormapRange", UniformType::Vec4, offsetof(ColormapUniforms, MapRange) },
		};
	}
};

/////////////////////////////////////////////////////////////////////////////

class PPTonemap
{
public:
	void Render(PPRenderState *renderstate);
	void ClearTonemapPalette() { PaletteTexture = {}; }

private:
	void UpdateTextures();

	PPTexture PaletteTexture;

	PPShader LinearShader = { "engine/shaders/pp/tonemap.fp", "#define LINEAR\n", {} };
	PPShader ReinhardShader = { "engine/shaders/pp/tonemap.fp", "#define REINHARD\n", {} };
	PPShader HejlDawsonShader = { "engine/shaders/pp/tonemap.fp", "#define HEJLDAWSON\n", {} };
	PPShader Uncharted2Shader = { "engine/shaders/pp/tonemap.fp", "#define UNCHARTED2\n", {} };
	PPShader PaletteShader = { "engine/shaders/pp/tonemap.fp", "#define PALETTE\n", {} };

	enum TonemapMode
	{
		None,
		Uncharted2,
		HejlDawson,
		Reinhard,
		Linear,
		Palette,
		NumTonemapModes
	};
};

/////////////////////////////////////////////////////////////////////////////

struct LinearDepthUniforms
{
	int SampleIndex;
	float LinearizeDepthA;
	float LinearizeDepthB;
	float InverseDepthRangeA;
	float InverseDepthRangeB;
	float Padding0, Padding1, Padding2;
	FVector2 Scale;
	FVector2 Offset;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "SampleIndex", UniformType::Int, offsetof(LinearDepthUniforms, SampleIndex) },
			{ "LinearizeDepthA", UniformType::Float, offsetof(LinearDepthUniforms, LinearizeDepthA) },
			{ "LinearizeDepthB", UniformType::Float, offsetof(LinearDepthUniforms, LinearizeDepthB) },
			{ "InverseDepthRangeA", UniformType::Float, offsetof(LinearDepthUniforms, InverseDepthRangeA) },
			{ "InverseDepthRangeB", UniformType::Float, offsetof(LinearDepthUniforms, InverseDepthRangeB) },
			{ "Padding0", UniformType::Float, offsetof(LinearDepthUniforms, Padding0) },
			{ "Padding1", UniformType::Float, offsetof(LinearDepthUniforms, Padding1) },
			{ "Padding2", UniformType::Float, offsetof(LinearDepthUniforms, Padding2) },
			{ "Scale", UniformType::Vec2, offsetof(LinearDepthUniforms, Scale) },
			{ "Offset", UniformType::Vec2, offsetof(LinearDepthUniforms, Offset) }
		};
	}
};

struct SSAOUniforms
{
	FVector2 UVToViewA;
	FVector2 UVToViewB;
	FVector2 InvFullResolution;
	float NDotVBias;
	float NegInvR2;
	float RadiusToScreen;
	float AOMultiplier;
	float AOStrength;
	int SampleIndex;
	float Padding0, Padding1;
	FVector2 Scale;
	FVector2 Offset;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "UVToViewA", UniformType::Vec2, offsetof(SSAOUniforms, UVToViewA) },
			{ "UVToViewB", UniformType::Vec2, offsetof(SSAOUniforms, UVToViewB) },
			{ "InvFullResolution", UniformType::Vec2, offsetof(SSAOUniforms, InvFullResolution) },
			{ "NDotVBias", UniformType::Float, offsetof(SSAOUniforms, NDotVBias) },
			{ "NegInvR2", UniformType::Float, offsetof(SSAOUniforms, NegInvR2) },
			{ "RadiusToScreen", UniformType::Float, offsetof(SSAOUniforms, RadiusToScreen) },
			{ "AOMultiplier", UniformType::Float, offsetof(SSAOUniforms, AOMultiplier) },
			{ "AOStrength", UniformType::Float, offsetof(SSAOUniforms, AOStrength) },
			{ "SampleIndex", UniformType::Int, offsetof(SSAOUniforms, SampleIndex) },
			{ "Padding0", UniformType::Float, offsetof(SSAOUniforms, Padding0) },
			{ "Padding1", UniformType::Float, offsetof(SSAOUniforms, Padding1) },
			{ "Scale", UniformType::Vec2, offsetof(SSAOUniforms, Scale) },
			{ "Offset", UniformType::Vec2, offsetof(SSAOUniforms, Offset) },
		};
	}
};

struct DepthBlurUniforms
{
	float BlurSharpness;
	float PowExponent;
	float Padding0, Padding1;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "BlurSharpness", UniformType::Float, offsetof(DepthBlurUniforms, BlurSharpness) },
			{ "PowExponent", UniformType::Float, offsetof(DepthBlurUniforms, PowExponent) },
			{ "Padding0", UniformType::Float, offsetof(DepthBlurUniforms, Padding0) },
			{ "Padding1", UniformType::Float, offsetof(DepthBlurUniforms, Padding1) }
		};
	}
};

struct AmbientCombineUniforms
{
	int SampleCount;
	int DebugMode, Padding1, Padding2;
	FVector2 Scale;
	FVector2 Offset;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "SampleCount", UniformType::Int, offsetof(AmbientCombineUniforms, SampleCount) },
			{ "DebugMode", UniformType::Int, offsetof(AmbientCombineUniforms, DebugMode) },
			{ "Padding1", UniformType::Int, offsetof(AmbientCombineUniforms, Padding1) },
			{ "Padding2", UniformType::Int, offsetof(AmbientCombineUniforms, Padding2) },
			{ "Scale", UniformType::Vec2, offsetof(AmbientCombineUniforms, Scale) },
			{ "Offset", UniformType::Vec2, offsetof(AmbientCombineUniforms, Offset) }
		};
	}
};

class PPAmbientOcclusion
{
public:
	PPAmbientOcclusion();
	void Render(PPRenderState *renderstate, float m5, int sceneWidth, int sceneHeight);

private:
	void CreateShaders();
	void UpdateTextures(int width, int height);

	enum Quality
	{
		Off,
		LowQuality,
		MediumQuality,
		HighQuality,
		NumQualityModes
	};

	int AmbientWidth = 0;
	int AmbientHeight = 0;

	int LastQuality = -1;
	int LastWidth = 0;
	int LastHeight = 0;

	PPShader LinearDepth;
	PPShader LinearDepthMS;
	PPShader AmbientOcclude;
	PPShader AmbientOccludeMS;
	PPShader BlurVertical;
	PPShader BlurHorizontal;
	PPShader Combine;
	PPShader CombineMS;

	PPTexture LinearDepthTexture;
	PPTexture Ambient0;
	PPTexture Ambient1;

	enum { NumAmbientRandomTextures = 3 };
	PPTexture AmbientRandomTexture[NumAmbientRandomTextures];
};

struct PresentUniforms
{
	float InvGamma;
	float Contrast;
	float Brightness;
	float Saturation;
	int GrayFormula;
	int WindowPositionParity; // top-of-window might not be top-of-screen
	FVector2 Scale;
	FVector2 Offset;
	float ColorScale;
	int HdrMode;

	static std::vector<UniformFieldDesc> Desc()
	{
		return
		{
			{ "InvGamma", UniformType::Float, offsetof(PresentUniforms, InvGamma) },
			{ "Contrast", UniformType::Float, offsetof(PresentUniforms, Contrast) },
			{ "Brightness", UniformType::Float, offsetof(PresentUniforms, Brightness) },
			{ "Saturation", UniformType::Float, offsetof(PresentUniforms, Saturation) },
			{ "GrayFormula", UniformType::Int, offsetof(PresentUniforms, GrayFormula) },
			{ "WindowPositionParity", UniformType::Int, offsetof(PresentUniforms, WindowPositionParity) },
			{ "UVScale", UniformType::Vec2, offsetof(PresentUniforms, Scale) },
			{ "UVOffset", UniformType::Vec2, offsetof(PresentUniforms, Offset) },
			{ "ColorScale", UniformType::Float, offsetof(PresentUniforms, ColorScale) },
			{ "HdrMode", UniformType::Int, offsetof(PresentUniforms, HdrMode) }
		};
	}
};

class PPPresent
{
public:
	PPPresent();

	PPTexture Dither;

	PPShader Present = { "engine/shaders/pp/present.fp", "", PresentUniforms::Desc() };
	PPShader Checker3D = { "engine/shaders/pp/present_checker3d.fp", "", PresentUniforms::Desc() };
	PPShader Column3D = { "engine/shaders/pp/present_column3d.fp", "", PresentUniforms::Desc() };
	PPShader Row3D = { "engine/shaders/pp/present_row3d.fp", "", PresentUniforms::Desc() };
};

/////////////////////////////////////////////////////////////////////////////

class Postprocess
{
public:
	PPBloom bloom;
	PPLensDistort lens;
	PPFXAA fxaa;
	PPCameraExposure exposure;
	PPTonemap tonemap;
	PPAmbientOcclusion ssao;
	PPPresent present;


	void Pass1(PPRenderState *state, int fixedcm, int sceneWidth, int sceneHeight);
	void Pass2(PPRenderState* state, int fixedcm, int sceneWidth, int sceneHeight);
};

extern Postprocess hw_postprocess;