From 63da6e70c0d4f2bbd05186cd14e781c6def9d208 Mon Sep 17 00:00:00 2001
From: Rachael Alexanderson <eruanna@drdteam.org>
Date: Sun, 25 Jun 2017 19:33:07 -0400
Subject: [PATCH] - added a vid_saturation control - works in postprocessing,
 only.

---
 src/gl/renderer/gl_postprocess.cpp    | 3 +++
 src/gl/shaders/gl_presentshader.cpp   | 1 +
 src/gl/shaders/gl_presentshader.h     | 1 +
 src/gl/stereo3d/gl_interleaved3d.cpp  | 2 ++
 src/gl/system/gl_menu.cpp             | 8 ++++++++
 wadsrc/static/shaders/glsl/present.fp | 4 +++-
 6 files changed, 18 insertions(+), 1 deletion(-)

diff --git a/src/gl/renderer/gl_postprocess.cpp b/src/gl/renderer/gl_postprocess.cpp
index acc0a08b4..92dd0bc80 100644
--- a/src/gl/renderer/gl_postprocess.cpp
+++ b/src/gl/renderer/gl_postprocess.cpp
@@ -149,6 +149,7 @@ CVAR(Float, gl_menu_blur, -1.0f, CVAR_ARCHIVE)
 
 EXTERN_CVAR(Float, vid_brightness)
 EXTERN_CVAR(Float, vid_contrast)
+EXTERN_CVAR(Float, vid_saturation)
 
 
 void FGLRenderer::RenderScreenQuad()
@@ -858,12 +859,14 @@ void FGLRenderer::DrawPresentTexture(const GL_IRECT &box, bool applyGamma)
 		mPresentShader->InvGamma.Set(1.0f);
 		mPresentShader->Contrast.Set(1.0f);
 		mPresentShader->Brightness.Set(0.0f);
+		mPresentShader->Saturation.Set(1.0f);
 	}
 	else
 	{
 		mPresentShader->InvGamma.Set(1.0f / clamp<float>(Gamma, 0.1f, 4.f));
 		mPresentShader->Contrast.Set(clamp<float>(vid_contrast, 0.1f, 3.f));
 		mPresentShader->Brightness.Set(clamp<float>(vid_brightness, -0.8f, 0.8f));
+		mPresentShader->Saturation.Set(clamp<float>(vid_saturation, -3.0f, 3.f));
 	}
 	mPresentShader->Scale.Set(mScreenViewport.width / (float)mBuffers->GetWidth(), mScreenViewport.height / (float)mBuffers->GetHeight());
 	RenderScreenQuad();
diff --git a/src/gl/shaders/gl_presentshader.cpp b/src/gl/shaders/gl_presentshader.cpp
index 5fe040db9..8fdf623d9 100644
--- a/src/gl/shaders/gl_presentshader.cpp
+++ b/src/gl/shaders/gl_presentshader.cpp
@@ -46,6 +46,7 @@ void FPresentShaderBase::Init(const char * vtx_shader_name, const char * program
 	InvGamma.Init(mShader, "InvGamma");
 	Contrast.Init(mShader, "Contrast");
 	Brightness.Init(mShader, "Brightness");
+	Saturation.Init(mShader, "Saturation");
 	Scale.Init(mShader, "UVScale");
 }
 
diff --git a/src/gl/shaders/gl_presentshader.h b/src/gl/shaders/gl_presentshader.h
index dcf42cdf8..acb3f50eb 100644
--- a/src/gl/shaders/gl_presentshader.h
+++ b/src/gl/shaders/gl_presentshader.h
@@ -12,6 +12,7 @@ public:
 	FBufferedUniform1f InvGamma;
 	FBufferedUniform1f Contrast;
 	FBufferedUniform1f Brightness;
+	FBufferedUniform1f Saturation;
 	FBufferedUniform2f Scale;
 
 protected:
diff --git a/src/gl/stereo3d/gl_interleaved3d.cpp b/src/gl/stereo3d/gl_interleaved3d.cpp
index 40aed85a9..686802e6a 100644
--- a/src/gl/stereo3d/gl_interleaved3d.cpp
+++ b/src/gl/stereo3d/gl_interleaved3d.cpp
@@ -41,6 +41,7 @@
 #include "gl/system/gl_framebuffer.h"
 #include "gl/shaders/gl_present3dRowshader.h"
 
+EXTERN_CVAR(Float, vid_saturation)
 EXTERN_CVAR(Float, vid_brightness)
 EXTERN_CVAR(Float, vid_contrast)
 EXTERN_CVAR(Bool, fullscreen)
@@ -106,6 +107,7 @@ static void prepareInterleavedPresent(FPresentStereoShaderBase& shader)
 		shader.InvGamma.Set(1.0f / clamp<float>(Gamma, 0.1f, 4.f));
 		shader.Contrast.Set(clamp<float>(vid_contrast, 0.1f, 3.f));
 		shader.Brightness.Set(clamp<float>(vid_brightness, -0.8f, 0.8f));
+		shader.Saturation.Set(clamp<float>(vid_saturation, -3.0f, 3.0f));
 	}
 	shader.Scale.Set(
 		GLRenderer->mScreenViewport.width / (float)GLRenderer->mBuffers->GetWidth(),
diff --git a/src/gl/system/gl_menu.cpp b/src/gl/system/gl_menu.cpp
index 8dffbc4f2..5813613b4 100644
--- a/src/gl/system/gl_menu.cpp
+++ b/src/gl/system/gl_menu.cpp
@@ -73,6 +73,14 @@ CUSTOM_CVAR (Float, vid_contrast, 1.f, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
 	}
 }
 
+CUSTOM_CVAR (Float, vid_saturation, 1.f, CVAR_ARCHIVE|CVAR_GLOBALCONFIG)
+{
+	if (screen != NULL)
+	{
+		screen->SetGamma(Gamma); //SetContrast (self);
+	}
+}
+
 
 // Do some tinkering with the menus so that certain options only appear
 // when they are actually valid.
diff --git a/wadsrc/static/shaders/glsl/present.fp b/wadsrc/static/shaders/glsl/present.fp
index 31c1217cb..3683d6bd1 100644
--- a/wadsrc/static/shaders/glsl/present.fp
+++ b/wadsrc/static/shaders/glsl/present.fp
@@ -6,10 +6,12 @@ uniform sampler2D InputTexture;
 uniform float InvGamma;
 uniform float Contrast;
 uniform float Brightness;
+uniform float Saturation;
 
 vec4 ApplyGamma(vec4 c)
 {
-	vec3 val = c.rgb * Contrast - (Contrast - 1.0) * 0.5;
+	vec3 valgray = (0.3 * c.r + 0.59 * c.g + 0.11 * c.b) * (1 - Saturation) + c.rgb * Saturation;
+	vec3 val = valgray * Contrast - (Contrast - 1.0) * 0.5;
 	val += Brightness * 0.5;
 	val = pow(max(val, vec3(0.0)), vec3(InvGamma));
 	return vec4(val, c.a);