gsdx ogl: extend shader to lookup a single channel

plugins/GSdx/GSDeviceOGL.cpp

@@ -778,6 +778,7 @@ GLuint GSDeviceOGL::CompilePS(PSSelector sel)
 		+ format("#define PS_TEX_FMT %d\n", sel.tex_fmt)
 		+ format("#define PS_DFMT %d\n", sel.dfmt)
 		+ format("#define PS_DEPTH_FMT %d\n", sel.depth_fmt)
+		+ format("#define PS_CHANNEL_FETCH %d\n", sel.channel)
 		+ format("#define PS_AEM %d\n", sel.aem)
 		+ format("#define PS_TFX %d\n", sel.tfx)
 		+ format("#define PS_TCC %d\n", sel.tcc)
@@ -920,42 +921,48 @@ void GSDeviceOGL::SelfShaderTest()
 	PRINT_TEST("Fst/Tc/IIp");
 
 	// Test: tfx/tcc
-	for (int tfx = 0; tfx < 5; tfx++) {
+	for (int channel = 0; channel < 5; channel++) {
-		for (int tcc = 0; tcc < 2; tcc++) {
+		for (int tfx = 0; tfx < 5; tfx++) {
-			PSSelector sel;
+			for (int tcc = 0; tcc < 2; tcc++) {
-			sel.atst = 1;
+				PSSelector sel;
-			sel.fst = 1;
+				sel.atst = 1;
+				sel.fst = 1;
 
-			sel.tfx = tfx;
+				sel.channel = channel;
-			sel.tcc = tcc;
+				sel.tfx     = tfx;
-			std::string file = format("Shader_Tfx_%d__Tcc_%d.glsl.asm", tfx, tcc);
+				sel.tcc     = tcc;
-			RUN_TEST;
+				std::string file = format("Shader_Tfx_%d__Tcc_%d__Channel_%d.glsl.asm", tfx, tcc, channel);
+				RUN_TEST;
+			}
 		}
 	}
-	PRINT_TEST("Tfx/Tcc");
+	PRINT_TEST("Tfx/Tcc/Channel");
 
 	// Test: Texture Sampling
-	for (int fmt = 0; fmt < 16; fmt++) {
+	for (int depth = 0; depth < 4; depth++) {
-		if ((fmt & 3) == 3) continue;
+		for (int fmt = 0; fmt < 16; fmt++) {
+			if ((fmt & 3) == 3) continue;
 
-		for (int ltf = 0; ltf < 2; ltf++) {
+			for (int ltf = 0; ltf < 2; ltf++) {
-			for (int aem = 0; aem < 2; aem++) {
+				for (int aem = 0; aem < 2; aem++) {
-				for (int wms = 1; wms < 4; wms++) {
+					for (int wms = 1; wms < 4; wms++) {
-					for (int wmt = 1; wmt < 4; wmt++) {
+						for (int wmt = 1; wmt < 4; wmt++) {
-						PSSelector sel;
+							PSSelector sel;
-						sel.atst = 1;
+							sel.atst = 1;
-						sel.tfx  = 1;
+							sel.tfx  = 1;
-						sel.tcc  = 1;
+							sel.tcc  = 1;
-						sel.fst = 1;
+							sel.fst = 1;
 
-						sel.ltf     = ltf;
+							sel.depth_fmt = depth;
-						sel.aem     = aem;
+							sel.ltf       = ltf;
-						sel.tex_fmt = fmt;
+							sel.aem       = aem;
-						sel.wms     = wms;
+							sel.tex_fmt   = fmt;
-						sel.wmt     = wmt;
+							sel.wms       = wms;
-						std::string file = format("Shader_Ltf_%d__Aem_%d__TFmt_%d__Wms_%d__Wmt_%d.glsl.asm",
+							sel.wmt       = wmt;
-								ltf, aem, fmt, wms, wmt);
+							std::string file = format("Shader_Ltf_%d__Aem_%d__TFmt_%d__Wms_%d__Wmt_%d__DepthFmt_%d.glsl.asm",
-						RUN_TEST;
+									ltf, aem, fmt, wms, wmt, depth);
+							RUN_TEST;
+						}
 					}
 				}
 			}

plugins/GSdx/GSDeviceOGL.h

@@ -284,10 +284,13 @@ class GSDeviceOGL final : public GSDevice
 				uint32 hdr:1;
 				uint32 colclip:1;
 
+				// Others ways to fetch the texture
+				uint32 channel:3;
+
 				// Hack
 				uint32 tcoffsethack:1;
 
-				uint32 _free2:19;
+				uint32 _free2:16;
 			};
 
 			uint64 key;

plugins/GSdx/res/glsl/tfx_fs.glsl

@@ -261,6 +261,34 @@ vec4 sample_depth(vec2 st)
 
     return t;
 }
+
+//////////////////////////////////////////////////////////////////////
+// Fetch a Single Channel
+//////////////////////////////////////////////////////////////////////
+vec4 fetch_red()
+{
+    vec4 rt = texelFetch(RtSampler, ivec2(gl_FragCoord.xy), 0);
+    return sample_p(rt.r) * 255.0f;
+}
+
+vec4 fetch_blue()
+{
+    vec4 rt = texelFetch(RtSampler, ivec2(gl_FragCoord.xy), 0);
+    return sample_p(rt.b) * 255.0f;
+}
+
+vec4 fetch_green()
+{
+    vec4 rt = texelFetch(RtSampler, ivec2(gl_FragCoord.xy), 0);
+    return sample_p(rt.g) * 255.0f;
+}
+
+vec4 fetch_alpha()
+{
+    vec4 rt = texelFetch(RtSampler, ivec2(gl_FragCoord.xy), 0);
+    return sample_p(rt.a) * 255.0f;
+}
+
 //////////////////////////////////////////////////////////////////////
 
 vec4 sample_color(vec2 st)
@@ -422,7 +450,15 @@ vec4 ps_color()
     vec2 st = PSin.t_int.xy;
 #endif
 
-#if (PS_DEPTH_FMT > 0)
+#if PS_CHANNEL_FETCH == 1
+    vec4 T = fetch_red();
+#elif PS_CHANNEL_FETCH == 2
+    vec4 T = fetch_green();
+#elif PS_CHANNEL_FETCH == 3
+    vec4 T = fetch_blue();
+#elif PS_CHANNEL_FETCH == 4
+    vec4 T = fetch_alpha();
+#elif PS_DEPTH_FMT > 0
     // Integral coordinate
     vec4 T = sample_depth(PSin.t_int.zw);
 #else

plugins/GSdx/res/glsl_source.h

@@ -1105,6 +1105,34 @@ static const char* const tfx_fs_all_glsl =
 	"\n"
 	"    return t;\n"
 	"}\n"
+	"\n"
+	"//////////////////////////////////////////////////////////////////////\n"
+	"// Fetch a Single Channel\n"
+	"//////////////////////////////////////////////////////////////////////\n"
+	"vec4 fetch_red()\n"
+	"{\n"
+	"    vec4 rt = texelFetch(RtSampler, ivec2(gl_FragCoord.xy), 0);\n"
+	"    return sample_p(rt.r) * 255.0f;\n"
+	"}\n"
+	"\n"
+	"vec4 fetch_blue()\n"
+	"{\n"
+	"    vec4 rt = texelFetch(RtSampler, ivec2(gl_FragCoord.xy), 0);\n"
+	"    return sample_p(rt.b) * 255.0f;\n"
+	"}\n"
+	"\n"
+	"vec4 fetch_green()\n"
+	"{\n"
+	"    vec4 rt = texelFetch(RtSampler, ivec2(gl_FragCoord.xy), 0);\n"
+	"    return sample_p(rt.g) * 255.0f;\n"
+	"}\n"
+	"\n"
+	"vec4 fetch_alpha()\n"
+	"{\n"
+	"    vec4 rt = texelFetch(RtSampler, ivec2(gl_FragCoord.xy), 0);\n"
+	"    return sample_p(rt.a) * 255.0f;\n"
+	"}\n"
+	"\n"
 	"//////////////////////////////////////////////////////////////////////\n"
 	"\n"
 	"vec4 sample_color(vec2 st)\n"
@@ -1266,7 +1294,15 @@ static const char* const tfx_fs_all_glsl =
 	"    vec2 st = PSin.t_int.xy;\n"
 	"#endif\n"
 	"\n"
-	"#if (PS_DEPTH_FMT > 0)\n"
+	"#if PS_CHANNEL_FETCH == 1\n"
+	"    vec4 T = fetch_red();\n"
+	"#elif PS_CHANNEL_FETCH == 2\n"
+	"    vec4 T = fetch_green();\n"
+	"#elif PS_CHANNEL_FETCH == 3\n"
+	"    vec4 T = fetch_blue();\n"
+	"#elif PS_CHANNEL_FETCH == 4\n"
+	"    vec4 T = fetch_alpha();\n"
+	"#elif PS_DEPTH_FMT > 0\n"
 	"    // Integral coordinate\n"
 	"    vec4 T = sample_depth(PSin.t_int.zw);\n"
 	"#else\n"