From d22fb24e28319cbfbba6a7654bd5eb689d849d58 Mon Sep 17 00:00:00 2001
From: Magnus Norddahl <dpjudas@users.noreply.github.com>
Date: Mon, 11 Jun 2018 20:58:20 +0200
Subject: [PATCH] - Uniform buffers for lens shader

---
 src/gl/renderer/gl_postprocess.cpp           |  9 ++++---
 src/gl/shaders/gl_lensshader.cpp             |  9 +++----
 src/gl/shaders/gl_lensshader.h               | 28 +++++++++++++++++---
 wadsrc/static/shaders/glsl/lensdistortion.fp |  4 ---
 4 files changed, 33 insertions(+), 17 deletions(-)

diff --git a/src/gl/renderer/gl_postprocess.cpp b/src/gl/renderer/gl_postprocess.cpp
index ce7e1ac61..a57b80b59 100644
--- a/src/gl/renderer/gl_postprocess.cpp
+++ b/src/gl/renderer/gl_postprocess.cpp
@@ -582,10 +582,11 @@ void FGLRenderer::LensDistortScene()
 	mBuffers->BindCurrentTexture(0, GL_LINEAR);
 	mLensShader->Bind();
 	mLensShader->InputTexture.Set(0);
-	mLensShader->AspectRatio.Set(aspect);
-	mLensShader->Scale.Set(scale);
-	mLensShader->LensDistortionCoefficient.Set(k);
-	mLensShader->CubicDistortionValue.Set(kcube);
+	mLensShader->Uniforms->AspectRatio = aspect;
+	mLensShader->Uniforms->Scale = scale;
+	mLensShader->Uniforms->LensDistortionCoefficient = k;
+	mLensShader->Uniforms->CubicDistortionValue = kcube;
+	mLensShader->Uniforms.Set();
 	RenderScreenQuad();
 	mBuffers->NextTexture();
 
diff --git a/src/gl/shaders/gl_lensshader.cpp b/src/gl/shaders/gl_lensshader.cpp
index 96ec217a3..13945e8eb 100644
--- a/src/gl/shaders/gl_lensshader.cpp
+++ b/src/gl/shaders/gl_lensshader.cpp
@@ -33,16 +33,15 @@ void FLensShader::Bind()
 {
 	if (!mShader)
 	{
+		FString prolog = Uniforms.CreateDeclaration("Uniforms", UniformBlock::Desc());
+
 		mShader.Compile(FShaderProgram::Vertex, "shaders/glsl/screenquad.vp", "", 330);
-		mShader.Compile(FShaderProgram::Fragment, "shaders/glsl/lensdistortion.fp", "", 330);
+		mShader.Compile(FShaderProgram::Fragment, "shaders/glsl/lensdistortion.fp", prolog, 330);
 		mShader.SetFragDataLocation(0, "FragColor");
 		mShader.Link("shaders/glsl/lensdistortion");
 		mShader.SetAttribLocation(0, "PositionInProjection");
 		InputTexture.Init(mShader, "InputTexture");
-		AspectRatio.Init(mShader, "Aspect");
-		Scale.Init(mShader, "Scale");
-		LensDistortionCoefficient.Init(mShader, "k");
-		CubicDistortionValue.Init(mShader, "kcube");
+		Uniforms.Init(mShader);
 	}
 	mShader.Bind();
 }
diff --git a/src/gl/shaders/gl_lensshader.h b/src/gl/shaders/gl_lensshader.h
index 7e9ef6392..ace6054cb 100644
--- a/src/gl/shaders/gl_lensshader.h
+++ b/src/gl/shaders/gl_lensshader.h
@@ -9,10 +9,30 @@ public:
 	void Bind();
 
 	FBufferedUniformSampler InputTexture;
-	FBufferedUniform1f AspectRatio;
-	FBufferedUniform1f Scale;
-	FBufferedUniform4f LensDistortionCoefficient;
-	FBufferedUniform4f CubicDistortionValue;
+
+	struct UniformBlock
+	{
+		float AspectRatio;
+		float Scale;
+		float Padding0, Padding1;
+		FVector4 LensDistortionCoefficient;
+		FVector4 CubicDistortionValue;
+
+		static std::vector<UniformFieldDesc> Desc()
+		{
+			return
+			{
+				{ "Aspect", UniformType::Float, offsetof(UniformBlock, AspectRatio) },
+				{ "Scale", UniformType::Float, offsetof(UniformBlock, Scale) },
+				{ "Padding0", UniformType::Float, offsetof(UniformBlock, Padding0) },
+				{ "Padding1", UniformType::Float, offsetof(UniformBlock, Padding1) },
+				{ "k", UniformType::Vec4, offsetof(UniformBlock, LensDistortionCoefficient) },
+				{ "kcube", UniformType::Vec4, offsetof(UniformBlock, CubicDistortionValue) }
+			};
+		}
+	};
+
+	ShaderUniforms<UniformBlock> Uniforms;
 
 private:
 	FShaderProgram mShader;
diff --git a/wadsrc/static/shaders/glsl/lensdistortion.fp b/wadsrc/static/shaders/glsl/lensdistortion.fp
index 7facf5a80..d3cc5c7ca 100644
--- a/wadsrc/static/shaders/glsl/lensdistortion.fp
+++ b/wadsrc/static/shaders/glsl/lensdistortion.fp
@@ -33,10 +33,6 @@ in vec2 TexCoord;
 out vec4 FragColor;
 
 uniform sampler2D InputTexture;
-uniform float Aspect; // image width/height
-uniform float Scale;  // 1/max(f)
-uniform vec4 k;       // lens distortion coefficient 
-uniform vec4 kcube;   // cubic distortion value
 
 void main()
 {