PostProcessing: Use Dubois algorithm for anaglyph shader.

1 files changed, 25 insertions, 5 deletions

diff --git a/Source/Core/VideoBackends/OGL/PostProcessing.cpp b/Source/Core/VideoBackends/OGL/PostProcessing.cpp
index 74fd93147b..cbcd1b0e9c 100644
--- a/Source/Core/VideoBackends/OGL/PostProcessing.cpp
+++ b/Source/Core/VideoBackends/OGL/PostProcessing.cpp
@@ -36,6 +36,28 @@ static char s_vertex_shader[] =
 	"	uv0 = rawpos * src_rect.zw + src_rect.xy;\n"
 	"}\n";
 
+// Anaglyph Red-Cyan shader based on Dubois algorithm
+// Constants taken from the paper:
+// "Conversion of a Stereo Pair to Anaglyph with
+// the Least-Squares Projection Method"
+// Eric Dubois, March 2009
+static char s_anaglyph_shader[] =
+	"void main() {\n"
+	"	vec3 l = SampleLayer(0).rgb;\n"
+	"	vec3 r = SampleLayer(1).rgb;\n"
+	"	vec3 lr = vec3(0.437,0.449,0.164);\n"
+	"	vec3 lg = vec3(-0.062,-0.062,-0.024);\n"
+	"	vec3 lb = vec3(-0.048,-0.050,-0.017);\n"
+	"	vec3 rr = vec3(-0.011,-0.032,-0.007);\n"
+	"	vec3 rg = vec3(0.377,0.761,0.009);\n"
+	"	vec3 rb = vec3(-0.026,-0.093,1.234);\n"
+	"	vec3 c0 = vec3(dot(l, lr), dot(l, lg), dot(l, lb));\n"
+	"	vec3 c1 = vec3(dot(r, rr), dot(r, rg), dot(r, rb));\n"
+	"	SetOutput(vec4(c0 + c1, SampleLayer(0).a));\n"
+	"}\n";
+
+static const char s_default_shader[] = "void main() { SetOutput(Sample()); }\n";
+
 OpenGLPostProcessing::OpenGLPostProcessing()
 	: m_initialized(false)
 	, m_anaglyph(false)
@@ -172,15 +194,13 @@ void OpenGLPostProcessing::ApplyShader()
 
 	// load shader code
 	std::string code = "";
-	std::string default_shader = "void main() { SetOutput(Sample()); }\n";
-
 	if (g_ActiveConfig.iStereoMode == STEREO_ANAGLYPH)
-		code = "void main() { SetOutput(float4(pow(0.7 * SampleLayer(0).g + 0.3 * SampleLayer(0).b, 1.5), SampleLayer(1).gba)); }\n";
+		code = s_anaglyph_shader;
 	else if (g_ActiveConfig.sPostProcessingShader != "")
 		code = m_config.LoadShader();
 
 	if (code == "")
-		code = default_shader;
+		code = s_default_shader;
 
 	code = LoadShaderOptions(code);
 
@@ -194,7 +214,7 @@ void OpenGLPostProcessing::ApplyShader()
 	{
 		ERROR_LOG(VIDEO, "Failed to compile post-processing shader %s", m_config.GetShader().c_str());
 
-		code = LoadShaderOptions(default_shader);
+		code = LoadShaderOptions(s_default_shader);
 		ProgramShaderCache::CompileShader(m_shader, vertex_shader, code.c_str());
 	}