Eevee : SSR : Make sure to not apply Specular Occlusion to SSR.

This makes the metals shine more.

Previous behaviour was not correct.

4 files changed, 48 insertions, 13 deletions

diff --git a/source/blender/draw/engines/eevee/eevee_effects.c b/source/blender/draw/engines/eevee/eevee_effects.c
index 4eead8d98f1..aa843e6e4c1 100644
--- a/source/blender/draw/engines/eevee/eevee_effects.c
+++ b/source/blender/draw/engines/eevee/eevee_effects.c
@@ -201,6 +201,7 @@ static struct GPUShader *eevee_effects_ssr_shader_get(int options)
 		BLI_dynstr_append(ds_frag, datatoc_bsdf_sampling_lib_glsl);
 		BLI_dynstr_append(ds_frag, datatoc_octahedron_lib_glsl);
 		BLI_dynstr_append(ds_frag, datatoc_lightprobe_lib_glsl);
+		BLI_dynstr_append(ds_frag, datatoc_ambient_occlusion_lib_glsl);
 		BLI_dynstr_append(ds_frag, datatoc_raytrace_lib_glsl);
 		BLI_dynstr_append(ds_frag, datatoc_effect_ssr_frag_glsl);
 		char *ssr_shader_str = BLI_dynstr_get_cstring(ds_frag);
@@ -997,6 +998,17 @@ void EEVEE_effects_cache_init(EEVEE_SceneLayerData *sldata, EEVEE_Data *vedata)
 		if (effects->ssr_ray_count > 3) {
 			DRW_shgroup_uniform_buffer(grp, "hitBuffer3", &stl->g_data->ssr_hit_output[3]);
 		}
+
+		DRW_shgroup_uniform_vec4(grp, "aoParameters[0]", &effects->ao_dist, 2);
+		if (effects->use_ao) {
+			DRW_shgroup_uniform_buffer(grp, "horizonBuffer", &vedata->txl->gtao_horizons);
+			DRW_shgroup_uniform_ivec2(grp, "aoHorizonTexSize", (int *)vedata->stl->effects->ao_texsize, 1);
+		}
+		else {
+			/* Use shadow_pool as fallback to avoid sampling problem on certain platform, see: T52593 */
+			DRW_shgroup_uniform_buffer(grp, "horizonBuffer", &sldata->shadow_pool);
+		}
+
 		DRW_shgroup_call_add(grp, quad, NULL);
 	}
 
diff --git a/source/blender/draw/engines/eevee/shaders/ambient_occlusion_lib.glsl b/source/blender/draw/engines/eevee/shaders/ambient_occlusion_lib.glsl
index 2202ee605fc..476de25fb54 100644
--- a/source/blender/draw/engines/eevee/shaders/ambient_occlusion_lib.glsl
+++ b/source/blender/draw/engines/eevee/shaders/ambient_occlusion_lib.glsl
@@ -327,7 +327,13 @@ float occlusion_compute(vec3 N, vec3 vpos, float user_occlusion, vec2 randuv, ou
 		float visibility;
 		vec3 vnor = mat3(ViewMatrix) * N;
 
-#if defined(MESH_SHADER) && !defined(USE_ALPHA_HASH) && !defined(USE_ALPHA_CLIP) && !defined(SHADOW_SHADER) && !defined(USE_MULTIPLY) && !defined(USE_ALPHA_BLEND)
+#if (defined(MESH_SHADER) && \
+	 !defined(USE_ALPHA_HASH) && \
+	 !defined(USE_ALPHA_CLIP) && \
+	 !defined(SHADOW_SHADER) && \
+	 !defined(USE_MULTIPLY) && \
+	 !defined(USE_ALPHA_BLEND)) \
+	|| defined(STEP_RESOLVE)
 		gtao_deferred(vnor, vpos, gl_FragCoord.z, visibility, bent_normal);
 #else
 		gtao(vnor, vpos, randuv, visibility, bent_normal);
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 520dc7b9624..7d142e50013 100644
--- a/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl
+++ b/source/blender/draw/engines/eevee/shaders/effect_ssr_frag.glsl
@@ -186,11 +186,16 @@ uniform mat4 PastViewProjectionMatrix;
 
 out vec4 fragColor;
 
-void fallback_cubemap(vec3 N, vec3 V, vec3 W, float roughness, float roughnessSquared, inout vec4 spec_accum)
+void fallback_cubemap(vec3 N, vec3 V, vec3 W, vec3 viewPosition, float roughness, float roughnessSquared, inout vec4 spec_accum)
 {
 	/* Specular probes */
 	vec3 spec_dir = get_specular_reflection_dominant_dir(N, V, roughnessSquared);
 
+	vec4 rand = texture(utilTex, vec3(gl_FragCoord.xy / LUT_SIZE, 2.0));
+	vec3 bent_normal;
+	float final_ao = occlusion_compute(N, viewPosition, 1.0, rand.rg, bent_normal);
+	final_ao = specular_occlusion(dot(N, V), final_ao, roughness);
+
 	/* Starts at 1 because 0 is world probe */
 	for (int i = 1; i < MAX_PROBE && i < probe_count && spec_accum.a < 0.999; ++i) {
 		CubeData cd = probes_data[i];
@@ -198,14 +203,14 @@ void fallback_cubemap(vec3 N, vec3 V, vec3 W, float roughness, float roughnessSq
 		float fade = probe_attenuation_cube(cd, W);
 
 		if (fade > 0.0) {
-			vec3 spec = probe_evaluate_cube(float(i), cd, W, spec_dir, roughness);
+			vec3 spec = final_ao * probe_evaluate_cube(float(i), cd, W, spec_dir, roughness);
 			accumulate_light(spec, fade, spec_accum);
 		}
 	}
 
 	/* World Specular */
 	if (spec_accum.a < 0.999) {
-		vec3 spec = probe_evaluate_world_spec(spec_dir, roughness);
+		vec3 spec = final_ao * probe_evaluate_world_spec(spec_dir, roughness);
 		accumulate_light(spec, 1.0, spec_accum);
 	}
 }
@@ -436,7 +441,7 @@ void main()
 
 	/* If SSR contribution is not 1.0, blend with cubemaps */
 	if (spec_accum.a < 1.0) {
-		fallback_cubemap(N, V, worldPosition, roughness, roughnessSquared, spec_accum);
+		fallback_cubemap(N, V, worldPosition, viewPosition, roughness, roughnessSquared, spec_accum);
 	}
 
 	fragColor = vec4(spec_accum.rgb * speccol_roughness.rgb, 1.0);
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 16b3283b624..e23effb854c 100644
--- a/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
+++ b/source/blender/draw/engines/eevee/shaders/lit_surface_frag.glsl
@@ -136,7 +136,10 @@ vec3 eevee_surface_lit(vec3 N, vec3 albedo, vec3 f0, float roughness, float ao,
 	vec2 uv = lut_coords(dot(N, V), roughness);
 	vec2 brdf_lut = texture(utilTex, vec3(uv, 1.0)).rg;
 
-	ssr_spec = F_ibl(f0, brdf_lut) * specular_occlusion(dot(N, V), final_ao, roughness);
+	ssr_spec = F_ibl(f0, brdf_lut);
+	if (!(ssrToggle && ssr_id == outputSsrId)) {
+		ssr_spec *= specular_occlusion(dot(N, V), final_ao, roughness);
+	}
 	out_light += spec_accum.rgb * ssr_spec * float(specToggle);
 
 	/* ---------------- DIFFUSE ENVIRONMENT LIGHTING ----------------- */
@@ -308,7 +311,10 @@ vec3 eevee_surface_clearcoat_lit(
 	vec2 uv = lut_coords(dot(N, V), roughness);
 	vec2 brdf_lut = texture(utilTex, vec3(uv, 1.0)).rg;
 
-	ssr_spec = F_ibl(f0, brdf_lut) * specular_occlusion(dot(N, V), final_ao, roughness);
+	ssr_spec = F_ibl(f0, brdf_lut);
+	if (!(ssrToggle && ssr_id == outputSsrId)) {
+		ssr_spec *= specular_occlusion(dot(N, V), final_ao, roughness);
+	}
 	out_light += spec_accum.rgb * ssr_spec * float(specToggle);
 
 	uv = lut_coords(dot(C_N, V), C_roughness);
@@ -533,15 +539,18 @@ vec3 eevee_surface_glossy_lit(vec3 N, vec3 f0, float roughness, float ao, int ss
 
 	vec4 rand = texture(utilTex, vec3(gl_FragCoord.xy / LUT_SIZE, 2.0));
 
-	/* Ambient Occlusion */
-	vec3 bent_normal;
-	float final_ao = occlusion_compute(N, viewPosition, ao, rand.rg, bent_normal);
-
 	/* Get Brdf intensity */
 	vec2 uv = lut_coords(dot(N, V), roughness);
 	vec2 brdf_lut = texture(utilTex, vec3(uv, 1.0)).rg;
 
-	ssr_spec = F_ibl(f0, brdf_lut) * specular_occlusion(dot(N, V), final_ao, roughness);
+	ssr_spec = F_ibl(f0, brdf_lut);
+	if (!(ssrToggle && ssr_id == outputSsrId)) {
+		/* Ambient Occlusion */
+		vec3 bent_normal;
+		float final_ao = occlusion_compute(N, viewPosition, ao, rand.rg, bent_normal);
+
+		ssr_spec *= specular_occlusion(dot(N, V), final_ao, roughness);
+	}
 	out_light += spec_accum.rgb * ssr_spec * float(specToggle);
 
 	return out_light;
@@ -785,7 +794,10 @@ vec3 eevee_surface_glass(vec3 N, vec3 transmission_col, float roughness, float i
 	/* Apply fresnel on lamps. */
 	out_light *= vec3(fresnel);
 
-	ssr_spec = vec3(fresnel) * F_ibl(vec3(1.0), brdf_lut) * specular_occlusion(NV, final_ao, roughness);
+	ssr_spec = vec3(fresnel) * F_ibl(vec3(1.0), brdf_lut);
+	if (!(ssrToggle && ssr_id == outputSsrId)) {
+		ssr_spec *= specular_occlusion(dot(N, V), final_ao, roughness);
+	}
 	out_light += spec_accum.rgb * ssr_spec;