CLASSIC: Add FXAA support.

src/gl_framebuffer.c

@@ -1001,3 +1001,13 @@ void GL_FramebufferDeleteAll(void)
 		GL_FramebufferEnsureDeleted(i);
 	}
 }
+
+int GL_FramebufferFxaaPreset(void)
+{
+	static const int fxaa_cvar_to_preset[18] = {
+			0, 10, 11, 12, 13, 14, 15, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 39
+	};
+	extern cvar_t vid_framebuffer_fxaa;
+
+	return fxaa_cvar_to_preset[bound(0, vid_framebuffer_fxaa.integer, 17)];
+}

src/gl_framebuffer.h

@@ -63,6 +63,7 @@ qbool GL_FramebufferEndWorldNormals(framebuffer_id id);
 
 int GL_FramebufferMultisamples(framebuffer_id framebuffer);
 void GL_FramebufferDeleteAll(void);
+int GL_FramebufferFxaaPreset(void);
 
 #define USE_FRAMEBUFFER_SCREEN    1
 #define USE_FRAMEBUFFER_3DONLY    2

src/glc_framebuffer.c

@@ -39,18 +39,21 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 
 #define POST_PROCESS_PALETTE    1
 #define POST_PROCESS_3DONLY     2
+#define POST_PROCESS_FXAA       4
 
 static texture_ref non_framebuffer_screen_texture;
 
 qbool GLC_CompilePostProcessProgram(void)
 {
 	extern cvar_t vid_software_palette, vid_framebuffer;
+	int fxaa_preset = GL_FramebufferFxaaPreset();
 	int post_process_flags =
 		(vid_software_palette.integer ? POST_PROCESS_PALETTE : 0) |
-		(vid_framebuffer.integer == USE_FRAMEBUFFER_3DONLY ? POST_PROCESS_3DONLY : 0);
+		(vid_framebuffer.integer == USE_FRAMEBUFFER_3DONLY ? POST_PROCESS_3DONLY : 0) |
+		(fxaa_preset > 0 ? POST_PROCESS_FXAA : 0) | (fxaa_preset << 4); // mix in preset to detect change
 
 	if (R_ProgramRecompileNeeded(r_program_post_process_glc, post_process_flags)) {
-		static char included_definitions[512];
+		static char included_definitions[131072];
 
 		memset(included_definitions, 0, sizeof(included_definitions));
 		if (post_process_flags & POST_PROCESS_PALETTE) {
@@ -59,6 +62,39 @@ qbool GLC_CompilePostProcessProgram(void)
 		if (post_process_flags & POST_PROCESS_3DONLY) {
 			strlcat(included_definitions, "#define EZ_POSTPROCESS_OVERLAY\n", sizeof(included_definitions));
 		}
+		if (post_process_flags & POST_PROCESS_FXAA) {
+			qbool supported = true;
+			if (!SDL_GL_ExtensionSupported("GL_EXT_gpu_shader4"))
+			{
+				Com_Printf("WARNING: Missing GL_EXT_gpu_shader4, FXAA not available.");
+				supported = false;
+			}
+#ifndef __APPLE__
+			if (!SDL_GL_ExtensionSupported("GL_ARB_gpu_shader5"))
+			{
+				Com_Printf("WARNING: Missing GL_ARB_gpu_shader5, FXAA not available.");
+				supported = false;
+			}
+#endif
+			if (supported)
+			{
+				extern const unsigned char fxaa_h_glsl[];
+				char buffer[33];
+				const char *settings =
+						"#extension GL_EXT_gpu_shader4 : enable\n"
+#ifndef __APPLE__
+						"#extension GL_ARB_gpu_shader5 : enable\n"
+#endif
+						"#define EZ_POSTPROCESS_FXAA\n"
+						"#define FXAA_PC 1\n"
+						"#define FXAA_GLSL_120 1\n"
+						"#define FXAA_GREEN_AS_LUMA 1\n";
+				snprintf(buffer, sizeof(buffer), "#define FXAA_QUALITY__PRESET %d\n", fxaa_preset);
+				strlcat(included_definitions, settings, sizeof(included_definitions));
+				strlcat(included_definitions, buffer, sizeof(included_definitions));
+				strlcat(included_definitions, (const char *)fxaa_h_glsl, sizeof(included_definitions));
+			}
+		}
 
 		// Initialise program for drawing image
 		R_ProgramCompileWithInclude(r_program_post_process_glc, included_definitions);

src/glm_framebuffer.c

@@ -43,7 +43,6 @@ Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 #define POST_PROCESS_FXAA            8
 
 extern cvar_t vid_software_palette, vid_framebuffer, vid_framebuffer_hdr, vid_framebuffer_hdr_tonemap, vid_framebuffer_multisample;
-extern cvar_t vid_framebuffer_fxaa;
 static texture_ref non_framebuffer_screen_texture;
 
 qbool GLM_CompilePostProcessVAO(void)
@@ -82,19 +81,15 @@ qbool GLM_CompilePostProcessVAO(void)
 	return R_VertexArrayCreated(vao_postprocess);
 }
 
-static const int fxaa_cvar_to_preset[18] = {
-		0, 10, 11, 12, 13, 14, 15, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 39
-};
-
 // If this returns false then the framebuffer will be blitted instead
 qbool GLM_CompilePostProcessProgram(void)
 {
-	int fxaa_preset = fxaa_cvar_to_preset[bound(0, vid_framebuffer_fxaa.integer, 17)];
+	int fxaa_preset = GL_FramebufferFxaaPreset();
 	int post_process_flags =
 		(vid_software_palette.integer ? POST_PROCESS_PALETTE : 0) |
 		(vid_framebuffer.integer == USE_FRAMEBUFFER_3DONLY ? POST_PROCESS_3DONLY : 0) |
 		(vid_framebuffer_hdr.integer && vid_framebuffer_hdr_tonemap.integer ? POST_PROCESS_TONEMAP : 0) |
-		(vid_framebuffer_fxaa.integer ? POST_PROCESS_FXAA : 0) | (fxaa_preset << 4); // mix in preset to detect change
+		(fxaa_preset > 0 ? POST_PROCESS_FXAA : 0) | (fxaa_preset << 4); // mix in preset to detect change
 
 	if (R_ProgramRecompileNeeded(r_program_post_process, post_process_flags)) {
 		static char included_definitions[131072];

src/glsl/glc/glc_post_process_screen.fragment.glsl

@@ -13,9 +13,46 @@ uniform float contrast;
 
 varying vec2 TextureCoord;
 
+vec4 sampleBase(void)
+{
+#ifdef EZ_POSTPROCESS_FXAA
+	// This is technically not the correct place to apply FXAA as it should sample
+	// a tonemapped, and gamma adjusted texture. However, the rendering pipeline
+	// prohibits this as this post_process_screen shader performs both tonemapping
+	// gamma, as well as combining HUD and world textures, so placing FXAA after
+	// this shader would apply FXAA to the HUD as well, which is detrimental.
+	// As it happens, applying FXAA to the world before tonemapping and gamma still
+	// looks ok, so it's still valuable without shuffling around shaders.
+	// Should world tonemap and gamma be broken out to a separate shader at some point
+	// that shader would ideally then also populate luma in the alpha channel, to be
+	// used by the FXAA algorithm instead of relying on green channel.
+	return FxaaPixelShader(
+		TextureCoord,                       // FxaaFloat2 pos,
+		FxaaFloat4(0.0f, 0.0f, 0.0f, 0.0f), // FxaaFloat4 fxaaConsolePosPos,
+		base,                               // FxaaTex tex,
+		base,                               // FxaaTex fxaaConsole360TexExpBiasNegOne,
+		base,                               // FxaaTex fxaaConsole360TexExpBiasNegTwo,
+		vec2(1.0/1280.0, 1.0/720.0),    // FxaaFloat2 fxaaQualityRcpFrame,
+		FxaaFloat4(0.0f, 0.0f, 0.0f, 0.0f), // FxaaFloat4 fxaaConsoleRcpFrameOpt,
+		FxaaFloat4(0.0f, 0.0f, 0.0f, 0.0f), // FxaaFloat4 fxaaConsoleRcpFrameOpt2,
+		FxaaFloat4(0.0f, 0.0f, 0.0f, 0.0f), // FxaaFloat4 fxaaConsole360RcpFrameOpt2,
+		0.75f,                              // FxaaFloat fxaaQualitySubpix (default),
+		0.166f,                             // FxaaFloat fxaaQualityEdgeThreshold (default),
+		0.0f,                               // FxaaFloat fxaaQualityEdgeThresholdMin (default if green as luma),
+		0.0f,                               // FxaaFloat fxaaConsoleEdgeSharpness,
+		0.0f,                               // FxaaFloat fxaaConsoleEdgeThreshold,
+		0.0f,                               // FxaaFloat fxaaConsoleEdgeThresholdMin,
+		FxaaFloat4(0.0f, 0.0f, 0.0f, 0.0f)  // FxaaFloat4 fxaaConsole360ConstDir,
+	);
+#else
+	return texture2D(base, TextureCoord);
+#endif
+}
+
+
 void main()
 {
-	vec4 frag_colour = texture2D(base, TextureCoord);
+	vec4 frag_colour = sampleBase();
 
 #ifdef EZ_POSTPROCESS_OVERLAY
 	vec4 add = texture2D(overlay, TextureCoord);