Eevee: SSR: Change clamp to a real clamp and add Max Roughness.

Clamp will now works as in Cycles.

Max roughness limit ssr to a certain roughness level: for noise / performance tweaking.

6 files changed, 63 insertions, 36 deletions

diff --git a/source/blender/draw/engines/eevee/eevee_effects.c b/source/blender/draw/engines/eevee/eevee_effects.c
index 6d1dadf06b5..7592e5c08d9 100644
--- a/source/blender/draw/engines/eevee/eevee_effects.c
+++ b/source/blender/draw/engines/eevee/eevee_effects.c
@@ -583,6 +583,11 @@ void EEVEE_effects_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata)
 		effects->ssr_thickness = BKE_collection_engine_property_value_get_float(props, "ssr_thickness");
 		effects->ssr_border_fac = BKE_collection_engine_property_value_get_float(props, "ssr_border_fade");
 		effects->ssr_firefly_fac = BKE_collection_engine_property_value_get_float(props, "ssr_firefly_fac");
+		effects->ssr_max_roughness = BKE_collection_engine_property_value_get_float(props, "ssr_max_roughness");
+
+		if (effects->ssr_firefly_fac < 1e-8f) {
+			effects->ssr_firefly_fac = FLT_MAX;
+		}
 
 		/* Important, can lead to breakage otherwise. */
 		CLAMP(effects->ssr_ray_count, 1, 4);
@@ -752,6 +757,7 @@ void EEVEE_effects_cache_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata)
 		DRW_shgroup_uniform_vec4(grp, "ssrParameters", &effects->ssr_quality, 1);
 		DRW_shgroup_uniform_int(grp, "rayCount", &effects->ssr_ray_count, 1);
 		DRW_shgroup_uniform_int(grp, "planar_count", &sldata->probes->num_planar, 1);
+		DRW_shgroup_uniform_float(grp, "maxRoughness", &effects->ssr_max_roughness, 1);
 		DRW_shgroup_uniform_buffer(grp, "planarDepth", &vedata->txl->planar_depth);
 		DRW_shgroup_uniform_block(grp, "planar_block", sldata->planar_ubo);
 		DRW_shgroup_call_add(grp, quad, NULL);
@@ -768,6 +774,7 @@ void EEVEE_effects_cache_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata)
 		DRW_shgroup_uniform_int(grp, "planar_count", &sldata->probes->num_planar, 1);
 		DRW_shgroup_uniform_int(grp, "probe_count", &sldata->probes->num_render_cube, 1);
 		DRW_shgroup_uniform_float(grp, "borderFadeFactor", &effects->ssr_border_fac, 1);
+		DRW_shgroup_uniform_float(grp, "maxRoughness", &effects->ssr_max_roughness, 1);
 		DRW_shgroup_uniform_float(grp, "lodCubeMax", &sldata->probes->lod_cube_max, 1);
 		DRW_shgroup_uniform_float(grp, "lodPlanarMax", &sldata->probes->lod_planar_max, 1);
 		DRW_shgroup_uniform_float(grp, "fireflyFactor", &effects->ssr_firefly_fac, 1);
@@ -1252,8 +1259,7 @@ void EEVEE_draw_effects(EEVEE_Data *vedata)
 				if (stl->g_data->ssr_hit_output[0]) DRW_transform_to_display(stl->g_data->ssr_hit_output[0]);
 				break;
 			case 3:
-				if (stl->g_data->ssr_hit_output[1]) DRW_transform_to_display(stl->g_data->ssr_hit_output[1]);
-				// if (txl->ssr_normal_input) DRW_transform_to_display(txl->ssr_normal_input);
+				if (txl->ssr_normal_input) DRW_transform_to_display(txl->ssr_normal_input);
 				break;
 			case 4:
 				if (txl->ssr_specrough_input) DRW_transform_to_display(txl->ssr_specrough_input);
diff --git a/source/blender/draw/engines/eevee/eevee_engine.c b/source/blender/draw/engines/eevee/eevee_engine.c
index ea72569b4d0..f2af9c53aa8 100644
--- a/source/blender/draw/engines/eevee/eevee_engine.c
+++ b/source/blender/draw/engines/eevee/eevee_engine.c
@@ -238,7 +238,8 @@ static void EEVEE_scene_layer_settings_create(RenderEngine *UNUSED(engine), IDPr
 	BKE_collection_engine_property_add_bool(props, "ssr_enable", false);
 	BKE_collection_engine_property_add_bool(props, "ssr_halfres", true);
 	BKE_collection_engine_property_add_int(props, "ssr_ray_count", 1);
-	BKE_collection_engine_property_add_float(props, "ssr_quality", 0.25);
+	BKE_collection_engine_property_add_float(props, "ssr_quality", 0.25f);
+	BKE_collection_engine_property_add_float(props, "ssr_max_roughness", 0.5f);
 	BKE_collection_engine_property_add_float(props, "ssr_thickness", 0.2f);
 	BKE_collection_engine_property_add_float(props, "ssr_border_fade", 0.075f);
 	BKE_collection_engine_property_add_float(props, "ssr_firefly_fac", 0.0f);
diff --git a/source/blender/draw/engines/eevee/eevee_private.h b/source/blender/draw/engines/eevee/eevee_private.h
index 115e2a25ea4..906f6a0f454 100644
--- a/source/blender/draw/engines/eevee/eevee_private.h
+++ b/source/blender/draw/engines/eevee/eevee_private.h
@@ -327,6 +327,7 @@ typedef struct EEVEE_EffectsInfo {
 	int ssr_ray_count;
 	float ssr_firefly_fac;
 	float ssr_border_fac;
+	float ssr_max_roughness;
 	float ssr_quality;
 	float ssr_thickness;
 	float ssr_pixelsize[2];
diff --git a/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl b/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl
index 673440c3d54..8e5ffb37e2e 100644
--- a/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl
+++ b/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl
@@ -8,6 +8,7 @@ uniform sampler2DArray utilTex;
 #endif /* UTIL_TEX */
 
 uniform int rayCount;
+uniform float maxRoughness;
 
 #define BRDF_BIAS 0.7
 
@@ -122,10 +123,16 @@ void main()
 	if (dot(speccol_roughness.rgb, vec3(1.0)) == 0.0)
 		discard;
 
+
 	float roughness = speccol_roughness.a;
 	float roughnessSquared = max(1e-3, roughness * roughness);
 	float a2 = roughnessSquared * roughnessSquared;
 
+	if (roughness > maxRoughness + 0.2) {
+		hitData0 = hitData1 = hitData2 = hitData3 = vec4(0.0);
+		return;
+	}
+
 	vec3 rand = texelFetch(utilTex, ivec3(halfres_texel % LUT_SIZE, 2), 0).rba;
 
 	vec3 worldPosition = transform_point(ViewMatrixInverse, viewPosition);
@@ -292,17 +299,17 @@ vec4 get_ssr_sample(
 		mask *= screen_border_mask(uvs);
 
 		/* Compute cone footprint Using UV distance because we are using screen space filtering. */
-		cone_footprint = 1.5 * cone_tan * distance(ref_uvs, source_uvs);
+		cone_footprint = cone_tan * distance(ref_uvs, source_uvs);
 	}
 	mask = min(mask, screen_border_mask(ref_uvs));
 	mask *= float(has_hit);
 
 	/* Estimate a cone footprint to sample a corresponding mipmap level. */
-	float mip = BRDF_BIAS * clamp(log2(cone_footprint * max(texture_size.x, texture_size.y)), 0.0, MAX_MIP);
+	float mip = BRDF_BIAS * clamp(log2(cone_footprint * max(texture_size.x, texture_size.y)), 0.0, MAX_MIP) - 1.0;
 
 	/* Slide 54 */
 	float bsdf = bsdf_ggx(N, L, V, roughnessSquared);
-	float weight = bsdf / max(1e-8, hit_co_pdf.w);
+	float weight = step(1e-8, hit_co_pdf.w) * bsdf / max(1e-8, hit_co_pdf.w);
 	weight_acc += weight;
 
 	vec3 sample;
@@ -313,12 +320,13 @@ vec4 get_ssr_sample(
 		sample = textureLod(colorBuffer, ref_uvs, mip).rgb;
 	}
 
+	/* Clamped brightness. */
+	float luma = max(1e-8, brightness(sample));
+	sample *= 1.0 - max(0.0, luma - fireflyFactor) / luma;
+
 	/* Do not add light if ray has failed. */
 	sample *= float(has_hit);
 
-	/* Firefly removal */
-	sample /= 1.0 + fireflyFactor * brightness(sample);
-
 	return vec4(sample, mask) * weight;
 }
 
@@ -397,26 +405,28 @@ void main()
 	invert_neighbor.x = ((fullres_texel.x & 0x1) == 0) ? 1 : -1;
 	invert_neighbor.y = ((fullres_texel.y & 0x1) == 0) ? 1 : -1;
 
-	for (int i = 0; i < NUM_NEIGHBORS; i++) {
-		ivec2 target_texel = halfres_texel + neighbors[i] * invert_neighbor;
+	if (roughness < maxRoughness + 0.2) {
+		for (int i = 0; i < NUM_NEIGHBORS; i++) {
+			ivec2 target_texel = halfres_texel + neighbors[i] * invert_neighbor;
 
-		ssr_accum += get_ssr_sample(hitBuffer0, pd, planar_index, worldPosition, N, V,
-		                            roughnessSquared, cone_tan, source_uvs,
-		                            texture_size, target_texel, weight_acc);
-		if (rayCount > 1) {
-			ssr_accum += get_ssr_sample(hitBuffer1, pd, planar_index, worldPosition, N, V,
-			                            roughnessSquared, cone_tan, source_uvs,
-			                            texture_size, target_texel, weight_acc);
-		}
-		if (rayCount > 2) {
-			ssr_accum += get_ssr_sample(hitBuffer2, pd, planar_index, worldPosition, N, V,
-			                            roughnessSquared, cone_tan, source_uvs,
-			                            texture_size, target_texel, weight_acc);
-		}
-		if (rayCount > 3) {
-			ssr_accum += get_ssr_sample(hitBuffer3, pd, planar_index, worldPosition, N, V,
+			ssr_accum += get_ssr_sample(hitBuffer0, pd, planar_index, worldPosition, N, V,
 			                            roughnessSquared, cone_tan, source_uvs,
 			                            texture_size, target_texel, weight_acc);
+			if (rayCount > 1) {
+				ssr_accum += get_ssr_sample(hitBuffer1, pd, planar_index, worldPosition, N, V,
+				                            roughnessSquared, cone_tan, source_uvs,
+				                            texture_size, target_texel, weight_acc);
+			}
+			if (rayCount > 2) {
+				ssr_accum += get_ssr_sample(hitBuffer2, pd, planar_index, worldPosition, N, V,
+				                            roughnessSquared, cone_tan, source_uvs,
+				                            texture_size, target_texel, weight_acc);
+			}
+			if (rayCount > 3) {
+				ssr_accum += get_ssr_sample(hitBuffer3, pd, planar_index, worldPosition, N, V,
+				                            roughnessSquared, cone_tan, source_uvs,
+				                            texture_size, target_texel, weight_acc);
+			}
 		}
 	}
 
@@ -424,7 +434,7 @@ void main()
 	if (weight_acc > 0.0) {
 		ssr_accum /= weight_acc;
 		/* fade between 0.5 and 1.0 roughness */
-		//ssr_accum.a *= saturate(2.0 - roughness * 2.0);
+		ssr_accum.a *= smoothstep(maxRoughness + 0.2, maxRoughness, roughness); 
 		accumulate_light(ssr_accum.rgb, ssr_accum.a, spec_accum);
 	}
 
diff --git a/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl b/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
index c5d44ba684a..21202a10fb0 100644
--- a/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
+++ b/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
@@ -91,7 +91,7 @@ vec3 eevee_surface_lit(vec3 N, vec3 albedo, vec3 f0, float roughness, float ao,
 	vec4 spec_accum = vec4(0.0);
 
 	/* SSR lobe is applied later in a defered style */
-	if (!ssrToggle || ssr_id != outputSsrId) {
+	if (!(ssrToggle && ssr_id == outputSsrId)) {
 		/* Planar Reflections */
 		for (int i = 0; i < MAX_PLANAR && i < planar_count && spec_accum.a < 0.999; ++i) {
 			PlanarData pd = planars_data[i];
@@ -238,7 +238,7 @@ vec3 eevee_surface_clearcoat_lit(
 		float fade = probe_attenuation_planar(pd, worldPosition, worldNormal, roughness);
 
 		if (fade > 0.0) {
-			if (!ssrToggle || ssr_id != outputSsrId) {
+			if (!(ssrToggle && ssr_id == outputSsrId)) {
 				vec3 spec = probe_evaluate_planar(float(i), pd, worldPosition, N, V, rand.r, roughness, fade);
 				accumulate_light(spec, fade, spec_accum);
 			}
@@ -259,7 +259,7 @@ vec3 eevee_surface_clearcoat_lit(
 		float fade = probe_attenuation_cube(cd, worldPosition);
 
 		if (fade > 0.0) {
-			if (!ssrToggle || ssr_id != outputSsrId) {
+			if (!(ssrToggle && ssr_id == outputSsrId)) {
 				vec3 spec = probe_evaluate_cube(float(i), cd, worldPosition, spec_dir, roughness);
 				accumulate_light(spec, fade, spec_accum);
 			}
@@ -271,7 +271,7 @@ vec3 eevee_surface_clearcoat_lit(
 
 	/* World Specular */
 	if (spec_accum.a < 0.999) {
-		if (!ssrToggle || ssr_id != outputSsrId) {
+		if (!(ssrToggle && ssr_id == outputSsrId)) {
 			vec3 spec = probe_evaluate_world_spec(spec_dir, roughness);
 			accumulate_light(spec, 1.0, spec_accum);
 		}
@@ -454,7 +454,7 @@ vec3 eevee_surface_glossy_lit(vec3 N, vec3 f0, float roughness, float ao, int ss
 	/* Accumulate light from all sources until accumulator is full. Then apply Occlusion and BRDF. */
 	vec4 spec_accum = vec4(0.0);
 
-	if (!ssrToggle || ssr_id != outputSsrId) {
+	if (!(ssrToggle && ssr_id == outputSsrId)) {
 		/* Planar Reflections */
 		for (int i = 0; i < MAX_PLANAR && i < planar_count && spec_accum.a < 0.999; ++i) {
 			PlanarData pd = planars_data[i];
diff --git a/source/blender/makesrna/intern/rna_scene.c b/source/blender/makesrna/intern/rna_scene.c
index 953bc134360..23907db522e 100644
--- a/source/blender/makesrna/intern/rna_scene.c
+++ b/source/blender/makesrna/intern/rna_scene.c
@@ -2629,6 +2629,7 @@ RNA_LAYER_ENGINE_EEVEE_GET_SET_BOOL(ssr_enable)
 RNA_LAYER_ENGINE_EEVEE_GET_SET_BOOL(ssr_halfres)
 RNA_LAYER_ENGINE_EEVEE_GET_SET_INT(ssr_ray_count)
 RNA_LAYER_ENGINE_EEVEE_GET_SET_FLOAT(ssr_quality)
+RNA_LAYER_ENGINE_EEVEE_GET_SET_FLOAT(ssr_max_roughness)
 RNA_LAYER_ENGINE_EEVEE_GET_SET_FLOAT(ssr_thickness)
 RNA_LAYER_ENGINE_EEVEE_GET_SET_FLOAT(ssr_border_fade)
 RNA_LAYER_ENGINE_EEVEE_GET_SET_FLOAT(ssr_firefly_fac)
@@ -6204,7 +6205,15 @@ static void rna_def_scene_layer_engine_settings_eevee(BlenderRNA *brna)
 	prop = RNA_def_property(srna, "ssr_quality", PROP_FLOAT, PROP_FACTOR);
 	RNA_def_property_float_funcs(prop, "rna_LayerEngineSettings_Eevee_ssr_quality_get",
 	                               "rna_LayerEngineSettings_Eevee_ssr_quality_set", NULL);
-	RNA_def_property_ui_text(prop, "Quality", "Quality of the screen space raytracing");
+	RNA_def_property_ui_text(prop, "Trace Quality", "Quality of the screen space raytracing");
+	RNA_def_property_range(prop, 0.0f, 1.0f);
+	RNA_def_property_flag(prop, PROP_CONTEXT_UPDATE);
+	RNA_def_property_update(prop, NC_SCENE | ND_LAYER_CONTENT, "rna_SceneLayerEngineSettings_update");
+
+	prop = RNA_def_property(srna, "ssr_max_roughness", PROP_FLOAT, PROP_FACTOR);
+	RNA_def_property_float_funcs(prop, "rna_LayerEngineSettings_Eevee_ssr_max_roughness_get",
+	                               "rna_LayerEngineSettings_Eevee_ssr_max_roughness_set", NULL);
+	RNA_def_property_ui_text(prop, "Max Roughness", "Do not raytrace reflections for roughness above this value");
 	RNA_def_property_range(prop, 0.0f, 1.0f);
 	RNA_def_property_flag(prop, PROP_CONTEXT_UPDATE);
 	RNA_def_property_update(prop, NC_SCENE | ND_LAYER_CONTENT, "rna_SceneLayerEngineSettings_update");
@@ -6234,11 +6243,11 @@ static void rna_def_scene_layer_engine_settings_eevee(BlenderRNA *brna)
 	RNA_def_property_flag(prop, PROP_CONTEXT_UPDATE);
 	RNA_def_property_update(prop, NC_SCENE | ND_LAYER_CONTENT, "rna_SceneLayerEngineSettings_update");
 
-	prop = RNA_def_property(srna, "ssr_firefly_fac", PROP_FLOAT, PROP_FACTOR);
+	prop = RNA_def_property(srna, "ssr_firefly_fac", PROP_FLOAT, PROP_NONE);
 	RNA_def_property_float_funcs(prop, "rna_LayerEngineSettings_Eevee_ssr_firefly_fac_get",
 	                               "rna_LayerEngineSettings_Eevee_ssr_firefly_fac_set", NULL);
-	RNA_def_property_ui_text(prop, "Clamp", "Smoothly clamp pixel intensity to remove noise");
-	RNA_def_property_range(prop, 0.0f, 1.0f);
+	RNA_def_property_ui_text(prop, "Clamp", "Clamp pixel intensity to remove noise (0 to disabled)");
+	RNA_def_property_range(prop, 0.0f, FLT_MAX);
 	RNA_def_property_flag(prop, PROP_CONTEXT_UPDATE);
 	RNA_def_property_update(prop, NC_SCENE | ND_LAYER_CONTENT, "rna_SceneLayerEngineSettings_update");