renderer: rework tone mapper and SSAO enablement

Author: illwieckz

src/engine/renderer/glsl_source/cameraEffects_fp.glsl

@@ -36,6 +36,8 @@ IN(smooth) vec2		var_TexCoords;
 
 DECLARE_OUTPUT(vec4)
 
+// Tone mapping is not available when high-precision float framebuffer isn't enabled or supported.
+#if defined(r_highPrecisionRendering) && defined(HAVE_ARB_texture_float)
 /* x: contrast
 y: highlightsCompressionSpeed
 z: shoulderClip
@@ -49,6 +51,7 @@ vec3 TonemapLottes( vec3 color ) {
   return pow( color, vec3( u_TonemapParms[0] ) )
          / ( pow( color, vec3( u_TonemapParms[0] * u_TonemapParms[1] ) ) * u_TonemapParms[2] + u_TonemapParms[3] );
 }
+#endif
 
 void main()
 {
@@ -58,9 +61,10 @@ void main()
 	vec4 color = texture2D(u_CurrentMap, st);
 	color *= u_GlobalLightFactor;
 
-	if( u_Tonemap ) {
-		color.rgb = TonemapLottes( color.rgb * u_TonemapExposure );
-	}
+#if defined(r_highPrecisionRendering) && defined(HAVE_ARB_texture_float)
+	color.rgb = TonemapLottes( color.rgb * u_TonemapExposure );
+#endif
+
 	color.rgb = clamp( color.rgb, vec3( 0.0f ), vec3( 1.0f ) );
 
 #if defined(r_colorGrading)

src/engine/renderer/tr_backend.cpp

@@ -151,7 +151,6 @@ void GL_BindNullProgram()
 
 void GL_SelectTexture( int unit )
 {
-
 	if ( glState.currenttmu == unit )
 	{
 		return;
@@ -3192,7 +3191,8 @@ void RB_RenderSSAO()
 {
 	GLimp_LogComment( "--- RB_RenderSSAO ---\n" );
 
-	if ( !glConfig2.textureGatherAvailable ) {
+	if ( !glConfig2.ssao )
+	{
 		return;
 	}
 
@@ -3205,7 +3205,7 @@ void RB_RenderSSAO()
 	GL_State( GLS_DEPTHTEST_DISABLE | GLS_SRCBLEND_DST_COLOR | GLS_DSTBLEND_ZERO );
 	GL_Cull( cullType_t::CT_TWO_SIDED );
 
-	if ( r_ssao->integer < 0 ) {
+	if ( glConfig2.ssao && r_ssao.Get() == Util::ordinal( ssaoMode::SHOW ) ) {
 		// clear the screen to show only SSAO
 		GL_ClearColor( 1.0, 1.0, 1.0, 1.0 );
 		glClear( GL_COLOR_BUFFER_BIT );
@@ -3355,13 +3355,13 @@ void RB_CameraPostFX()
 
 	gl_cameraEffectsShader->SetUniform_InverseGamma( 1.0 / r_gamma->value );
 
-	const bool tonemap = r_tonemap.Get() && r_highPrecisionRendering.Get() && glConfig2.textureFloatAvailable;
+	const bool tonemap = r_toneMapping.Get() && r_highPrecisionRendering.Get() && glConfig2.textureFloatAvailable;
 	if ( tonemap ) {
-		vec4_t tonemapParms { r_tonemapContrast.Get(), r_tonemapHighlightsCompressionSpeed.Get() };
-		ComputeTonemapParams( tonemapParms[0], tonemapParms[1], r_tonemapHDRMax.Get(),
-			r_tonemapDarkAreaPointHDR.Get(), r_tonemapDarkAreaPointLDR.Get(), tonemapParms[2], tonemapParms[3] );
+		vec4_t tonemapParms { r_toneMappingContrast.Get(), r_toneMappingHighlightsCompressionSpeed.Get() };
+		ComputeTonemapParams( tonemapParms[0], tonemapParms[1], r_toneMappingHDRMax.Get(),
+			r_toneMappingDarkAreaPointHDR.Get(), r_toneMappingDarkAreaPointLDR.Get(), tonemapParms[2], tonemapParms[3] );
 		gl_cameraEffectsShader->SetUniform_TonemapParms( tonemapParms );
-		gl_cameraEffectsShader->SetUniform_TonemapExposure( r_tonemapExposure.Get() );
+		gl_cameraEffectsShader->SetUniform_TonemapExposure( r_toneMappingExposure.Get() );
 	}
 	gl_cameraEffectsShader->SetUniform_Tonemap( tonemap );
 
@@ -4726,9 +4726,7 @@ static void RB_RenderView( bool depthPass )
 		RB_RenderDrawSurfaces( shaderSort_t::SS_ENVIRONMENT_FOG, shaderSort_t::SS_OPAQUE, DRAWSURFACES_ALL );
 	}
 
-	if ( r_ssao->integer ) {
-		RB_RenderSSAO();
-	}
+	RB_RenderSSAO();
 
 	if ( r_speeds->integer == Util::ordinal(renderSpeeds_t::RSPEEDS_SHADING_TIMES) )
 	{

src/engine/renderer/tr_init.cpp

@@ -209,20 +209,24 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 
 	cvar_t      *r_gamma;
 
-	Cvar::Cvar<bool> r_tonemap( "r_tonemap", "Use  HDR->LDR tonemapping", Cvar::NONE, true );
-	Cvar::Cvar<float> r_tonemapExposure( "r_tonemapExposure", "Tonemap exposure", Cvar::NONE, 1.0f );
-	Cvar::Range<Cvar::Cvar<float>> r_tonemapContrast( "r_tonemapContrast", "Makes dark areas light up faster",
+	Cvar::Cvar<bool> r_toneMapping(
+		"r_toneMapping", "Use  HDR->LDR tonemapping", Cvar::NONE, true );
+	Cvar::Cvar<float> r_toneMappingExposure(
+		"r_toneMappingExposure", "Tonemap exposure", Cvar::NONE, 1.0f );
+	Cvar::Range<Cvar::Cvar<float>> r_toneMappingContrast(
+		"r_toneMappingContrast", "Makes dark areas light up faster",
 		Cvar::NONE, 1.6f, 1.0f, 10.0f );
-	Cvar::Range<Cvar::Cvar<float>> r_tonemapHighlightsCompressionSpeed( "r_tonemapHighlightsCompressionSpeed",
-		"Highlights saturation",
+	Cvar::Range<Cvar::Cvar<float>> r_toneMappingHighlightsCompressionSpeed(
+		"r_toneMappingHighlightsCompressionSpeed", "Highlights saturation",
 		Cvar::NONE, 0.977f, 0.0f, 10.0f );
-	Cvar::Range<Cvar::Cvar<float>> r_tonemapHDRMax( "r_tonemapHDRMax", "HDR white point",
+	Cvar::Range<Cvar::Cvar<float>> r_toneMappingHDRMax(
+		"r_toneMappingHDRMax", "HDR white point",
 		Cvar::NONE, 8.0f, 1.0f, 128.0f );
-	Cvar::Range<Cvar::Cvar<float>> r_tonemapDarkAreaPointHDR( "r_tonemapDarkAreaPointHDR",
-		"Cut-off for dark area light-up",
+	Cvar::Range<Cvar::Cvar<float>> r_toneMappingDarkAreaPointHDR(
+		"r_toneMappingDarkAreaPointHDR", "Cut-off for dark area light-up",
 		Cvar::NONE, 0.18f, 0.0f, 1.0f );
-	Cvar::Range<Cvar::Cvar<float>> r_tonemapDarkAreaPointLDR( "r_tonemapDarkAreaPointLDR",
-		"Convert to this brightness at dark area cut-off",
+	Cvar::Range<Cvar::Cvar<float>> r_toneMappingDarkAreaPointLDR(
+		"r_toneMappingDarkAreaPointLDR", "Convert to this brightness at dark area cut-off",
 		Cvar::NONE, 0.268f, 0.0f, 1.0f );
 
 	cvar_t      *r_lockpvs;
@@ -316,7 +320,13 @@ Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 	Cvar::Cvar<float> r_bloomBlur( "r_bloomBlur", "Bloom strength", Cvar::NONE, 1.0 );
 	Cvar::Cvar<int> r_bloomPasses( "r_bloomPasses", "Amount of bloom passes in each direction", Cvar::NONE, 2 );
 	cvar_t      *r_FXAA;
-	cvar_t      *r_ssao;
+	Cvar::Range<Cvar::Cvar<int>> r_ssao( "r_ssao",
+		"Screen space ambient occlusion: "
+		"-1: show, 0: disabled, 1: enabled",
+		Cvar::NONE,
+		Util::ordinal( ssaoMode::DISABLED ),
+		Util::ordinal( ssaoMode::SHOW ),
+		Util::ordinal( ssaoMode::ENABLED ) );
 
 	cvar_t      *r_evsmPostProcess;
 
@@ -1246,7 +1256,7 @@ ScreenshotCmd screenshotPNGRegistration("screenshotPNG", ssFormat_t::SSF_PNG, "p
 
 		Cvar::Latch( r_bloom );
 		r_FXAA = Cvar_Get( "r_FXAA", "0", CVAR_LATCH | CVAR_ARCHIVE );
-		r_ssao = Cvar_Get( "r_ssao", "0", CVAR_LATCH | CVAR_ARCHIVE );
+		Cvar::Latch( r_ssao );
 
 		// temporary variables that can change at any time
 		r_showImages = Cvar_Get( "r_showImages", "0", CVAR_TEMP );

src/engine/renderer/tr_local.h

@@ -321,6 +321,12 @@ enum class shaderProfilerRenderSubGroupsMode {
 	FS_ALL
 };
 
+enum class ssaoMode {
+	SHOW = -1,
+	DISABLED,
+	ENABLED,
+};
+
 	enum class renderSpeeds_t
 	{
 	  RSPEEDS_GENERAL = 1,
@@ -2964,13 +2970,13 @@ enum class shaderProfilerRenderSubGroupsMode {
 	extern cvar_t *r_mode; // video mode
 	extern cvar_t *r_gamma;
 
-	extern Cvar::Cvar<bool> r_tonemap;
-	extern Cvar::Cvar<float> r_tonemapExposure;
-	extern Cvar::Range<Cvar::Cvar<float>> r_tonemapContrast;
-	extern Cvar::Range<Cvar::Cvar<float>> r_tonemapHighlightsCompressionSpeed;
-	extern Cvar::Range<Cvar::Cvar<float>> r_tonemapHDRMax;
-	extern Cvar::Range<Cvar::Cvar<float>> r_tonemapDarkAreaPointHDR;
-	extern Cvar::Range<Cvar::Cvar<float>> r_tonemapDarkAreaPointLDR;
+	extern Cvar::Cvar<bool> r_toneMapping;
+	extern Cvar::Cvar<float> r_toneMappingExposure;
+	extern Cvar::Range<Cvar::Cvar<float>> r_toneMappingContrast;
+	extern Cvar::Range<Cvar::Cvar<float>> r_toneMappingHighlightsCompressionSpeed;
+	extern Cvar::Range<Cvar::Cvar<float>> r_toneMappingHDRMax;
+	extern Cvar::Range<Cvar::Cvar<float>> r_toneMappingDarkAreaPointHDR;
+	extern Cvar::Range<Cvar::Cvar<float>> r_toneMappingDarkAreaPointLDR;
 
 	extern cvar_t *r_nobind; // turns off binding to appropriate textures
 	extern cvar_t *r_singleShader; // make most world faces use default shader
@@ -3109,7 +3115,7 @@ enum class shaderProfilerRenderSubGroupsMode {
 	extern Cvar::Cvar<float> r_bloomBlur;
 	extern Cvar::Cvar<int> r_bloomPasses;
 	extern cvar_t *r_FXAA;
-	extern cvar_t *r_ssao;
+	extern Cvar::Range<Cvar::Cvar<int>> r_ssao;
 
 	extern cvar_t *r_evsmPostProcess;
 

src/engine/renderer/tr_public.h

@@ -152,6 +152,7 @@ struct glconfig2_t
 	bool reflectionMappingAvailable;
 	bool reflectionMapping;
 	bool bloom;
+	bool ssao;
 	bool motionBlur;
 };
 

src/engine/renderer/tr_shade.cpp

@@ -73,7 +73,7 @@ static void EnableAvailableFeatures()
 
 		if ( glConfig2.realtimeLightLayers > glConfig2.max3DTextureSize ) {
 			glConfig2.realtimeLightLayers = glConfig2.max3DTextureSize;
-			Log::Notice( "r_realtimeLightLayers exceeds maximum 3D texture size, using %i instead", glConfig2.max3DTextureSize );
+			Log::Notice( "r_realtimeLightLayers exceeds maximum 3D texture size, using %i instead.", glConfig2.max3DTextureSize );
 		}
 
 		Log::Notice( "Using %i dynamic light layers, %i dynamic lights available per tile", glConfig2.realtimeLightLayers,
@@ -98,7 +98,7 @@ static void EnableAvailableFeatures()
 	{
 		if ( !glConfig2.textureFloatAvailable )
 		{
-			Log::Warn( "Shadow mapping disabled because ARB_texture_float is not available" );
+			Log::Warn( "Shadow mapping disabled because ARB_texture_float is not available." );
 			glConfig2.shadowMapping = false;
 		}
 	}
@@ -136,14 +136,29 @@ static void EnableAvailableFeatures()
 		}
 	}
 
-
 	// Disable features that require deluxe mapping to be enabled.
 	glConfig2.normalMapping = glConfig2.deluxeMapping && glConfig2.normalMapping;
 	glConfig2.specularMapping = glConfig2.deluxeMapping && glConfig2.specularMapping;
 	glConfig2.physicalMapping = glConfig2.deluxeMapping && glConfig2.physicalMapping;
 
 	glConfig2.bloom = r_bloom.Get();
 
+	glConfig2.ssao = r_ssao.Get() != Util::ordinal( ssaoMode::DISABLED );
+
+	static const std::pair<bool*, std::string> ssaoRequiredExtensions[] = {
+		{ &glConfig2.textureGatherAvailable, "ARB_texture_gather" },
+		{ &glConfig2.gpuShader4Available, "EXT_gpu_shader4" },
+	};
+
+	for ( auto& e: ssaoRequiredExtensions )
+	{
+		if ( !*e.first )
+		{
+			Log::Warn( "SSAO disabled because %s is not available.", e.second );
+			glConfig2.ssao = false;
+		}
+	}
+
 	/* Motion blur is enabled by cg_motionblur which is a client cvar so we have to build it in all cases,
 	unless unsupported by the hardware which is the only condition when the engine knows it is not used. */
 	glConfig2.motionBlur = true;
@@ -369,16 +384,9 @@ static void GLSL_InitGPUShadersOrError()
 		gl_shaderManager.LoadShader( gl_motionblurShader );
 	}
 
-	if ( r_ssao->integer )
+	if ( glConfig2.ssao )
 	{
-		if ( glConfig2.textureGatherAvailable )
-		{
-			gl_shaderManager.LoadShader( gl_ssaoShader );
-		}
-		else
-		{
-			Log::Warn("SSAO not used because GL_ARB_texture_gather is not available.");
-		}
+		gl_shaderManager.LoadShader( gl_ssaoShader );
 	}
 
 	if ( r_FXAA->integer != 0 )