gsdx: add some helper to debug openGL renderer

plugins/GSdx/GSShaderOGL.cpp

@@ -104,7 +104,10 @@ void GSShaderOGL::PS(GLuint s, GLuint sub_count)
 	{
 		m_ps_sub_count = sub_count;
 
+#ifndef _DEBUG
+		// In debug always sets the program. It allow to replace the program in apitrace easily.
 		GLState::ps = s;
+#endif
 		GLState::dirty_prog = true;
 		GLState::dirty_subroutine_ps = true;
 		GLState::dirty_ressources = true;

plugins/GSdx/res/glsl_source.h

@@ -458,6 +458,8 @@ static const char* tfx_glsl =
 	"#define FMT_16 2\n"
 	"#define FMT_PAL 4 /* flag bit */\n"
 	"\n"
+	"#define APITRACE_DEBUG 0\n"
+	"\n"
 	"// Not sure we have same issue on opengl. Doesn't work anyway on ATI card\n"
 	"// And I say this as an ATI user.\n"
 	"#define ATI_SUCKS 0\n"
@@ -1477,6 +1479,18 @@ static const char* tfx_glsl =
 	"#endif\n"
 	"\n"
 	"    vec4 c = ps_color();\n"
+	"#if (APITRACE_DEBUG & 1) == 1\n"
+	"	c.r = 1.0f;\n"
+	"#endif\n"
+	"#if (APITRACE_DEBUG & 2) == 2\n"
+	"	c.g = 1.0f;\n"
+	"#endif\n"
+	"#if (APITRACE_DEBUG & 4) == 4\n"
+	"	c.b = 1.0f;\n"
+	"#endif\n"
+	"#if (APITRACE_DEBUG & 8) == 8\n"
+	"	c.a = 0.5f;\n"
+	"#endif\n"
 	"\n"
 	"    float alpha = c.a * 2.0;\n"
 	"\n"

plugins/GSdx/res/tfx.glsl

@@ -7,6 +7,8 @@
 #define FMT_16 2
 #define FMT_PAL 4 /* flag bit */
 
+#define APITRACE_DEBUG 0
+
 // Not sure we have same issue on opengl. Doesn't work anyway on ATI card
 // And I say this as an ATI user.
 #define ATI_SUCKS 0
@@ -1026,6 +1028,18 @@ void ps_main()
 #endif
 
     vec4 c = ps_color();
+#if (APITRACE_DEBUG & 1) == 1
+	c.r = 1.0f;
+#endif
+#if (APITRACE_DEBUG & 2) == 2
+	c.g = 1.0f;
+#endif
+#if (APITRACE_DEBUG & 4) == 4
+	c.b = 1.0f;
+#endif
+#if (APITRACE_DEBUG & 8) == 8
+	c.a = 0.5f;
+#endif
 
     float alpha = c.a * 2.0;