glsl: add an HLE shader for Urban Chaos

Pro:
* Replace 140 draw calls into a single one
* No complex texture conversion/lookup
* smaller solution than a generic solution

plugins/GSdx/GSDeviceOGL.cpp

@@ -779,6 +779,7 @@ GLuint GSDeviceOGL::CompilePS(PSSelector sel)
 		+ 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_URBAN_CHAOS_HACK %d\n", sel.urban_chaos_hack)
 		+ format("#define PS_AEM %d\n", sel.aem)
 		+ format("#define PS_TFX %d\n", sel.tfx)
 		+ format("#define PS_TCC %d\n", sel.tcc)

plugins/GSdx/GSDeviceOGL.h

@@ -289,8 +289,9 @@ class GSDeviceOGL final : public GSDevice
 
 				// Hack
 				uint32 tcoffsethack:1;
+				uint32 urban_chaos_hack:1;
 
-				uint32 _free2:16;
+				uint32 _free2:15;
 			};
 
 			uint64 key;

plugins/GSdx/GSRendererOGL.cpp

@@ -773,6 +773,10 @@ void GSRendererOGL::DrawPrims(GSTexture* rt, GSTexture* ds, GSTextureCache::Sour
 			// Pop
 			GL_INS("Red channel");
 			ps_sel.channel = 1;
+		} else if (0 && (tex->m_texture->GetType() == GSTexture::DepthStencil) /*&& !(rt->m_32_bits_fmt)*/) {
+			// FIXME add a 16 bit check
+			GL_INS("Urban Chaos Crazyness");
+			ps_sel.urban_chaos_hack = 1;
 		} else {
 			GL_INS("channel not supported");
 			m_channel_shuffle = false;

plugins/GSdx/res/glsl/tfx_fs.glsl

@@ -225,7 +225,21 @@ vec4 sample_depth(vec2 st)
     ivec2 uv = ivec2(uv_f);
 
     vec4 t;
-#if PS_DEPTH_FMT == 1
+#if PS_URBAN_CHAOS_HACK == 1
+    // Convert a GL_FLOAT32 to a special color format expected by the game
+    int depth = int(fetch_c(uv).r * exp2(32.0f));
+
+    // Convert lsb based on the palette
+    t = texelFetch(PaletteSampler, ivec2((depth & 0xFF), 0), 0);
+
+    // Msb is easier
+    float green = float((depth >> 8) & 0xFF) * 36.0f;
+    green = min(green, 255.0f);
+
+    t.g += green;
+
+
+#elif PS_DEPTH_FMT == 1
     // Based on ps_main11 of convert
 
     // Convert a GL_FLOAT32 depth texture into a RGBA color texture
@@ -252,6 +266,7 @@ vec4 sample_depth(vec2 st)
 
 #endif
 
+
     // warning t ranges from 0 to 255
 #if (PS_AEM_FMT == FMT_24)
     t.a = ( (PS_AEM == 0) || any(bvec3(t.rgb))  ) ? 255.0f * TA.x : 0.0f;

plugins/GSdx/res/glsl_source.h

@@ -1069,7 +1069,21 @@ static const char* const tfx_fs_all_glsl =
 	"    ivec2 uv = ivec2(uv_f);\n"
 	"\n"
 	"    vec4 t;\n"
-	"#if PS_DEPTH_FMT == 1\n"
+	"#if PS_URBAN_CHAOS_HACK == 1\n"
+	"    // Convert a GL_FLOAT32 to a special color format expected by the game\n"
+	"    int depth = int(fetch_c(uv).r * exp2(32.0f));\n"
+	"\n"
+	"    // Convert lsb based on the palette\n"
+	"    t = texelFetch(PaletteSampler, ivec2((depth & 0xFF), 0), 0);\n"
+	"\n"
+	"    // Msb is easier\n"
+	"    float green = float((depth >> 8) & 0xFF) * 36.0f;\n"
+	"    green = min(green, 255.0f);\n"
+	"\n"
+	"    t.g += green;\n"
+	"\n"
+	"\n"
+	"#elif PS_DEPTH_FMT == 1\n"
 	"    // Based on ps_main11 of convert\n"
 	"\n"
 	"    // Convert a GL_FLOAT32 depth texture into a RGBA color texture\n"
@@ -1096,6 +1110,7 @@ static const char* const tfx_fs_all_glsl =
 	"\n"
 	"#endif\n"
 	"\n"
+	"\n"
 	"    // warning t ranges from 0 to 255\n"
 	"#if (PS_AEM_FMT == FMT_24)\n"
 	"    t.a = ( (PS_AEM == 0) || any(bvec3(t.rgb))  ) ? 255.0f * TA.x : 0.0f;\n"