Add specular occlusion from ambient light

Co-authored-by: guerro323 <[email protected]>

doc/classes/BaseMaterial3D.xml

@@ -182,6 +182,9 @@
 		<member name="disable_receive_shadows" type="bool" setter="set_flag" getter="get_flag" default="false">
 			If [code]true[/code], the object receives no shadow that would otherwise be cast onto it.
 		</member>
+		<member name="disable_specular_occlusion" type="bool" setter="set_flag" getter="get_flag" default="false">
+			If [code]true[/code], disables specular occlusion even if [member ProjectSettings.rendering/reflections/specular_occlusion/enabled] is [code]false[/code].
+		</member>
 		<member name="distance_fade_max_distance" type="float" setter="set_distance_fade_max_distance" getter="get_distance_fade_max_distance" default="10.0">
 			Distance at which the object appears fully opaque.
 			[b]Note:[/b] If [member distance_fade_max_distance] is less than [member distance_fade_min_distance], the behavior will be reversed. The object will start to fade away at [member distance_fade_max_distance] and will fully disappear once it reaches [member distance_fade_min_distance].
@@ -706,7 +709,10 @@
 		<constant name="FLAG_DISABLE_FOG" value="21" enum="Flags">
 			Disables receiving depth-based or volumetric fog.
 		</constant>
-		<constant name="FLAG_MAX" value="22" enum="Flags">
+		<constant name="FLAG_DISABLE_SPECULAR_OCCLUSION" value="22" enum="Flags">
+			Disables specular occlusion.
+		</constant>
+		<constant name="FLAG_MAX" value="23" enum="Flags">
 			Represents the size of the [enum Flags] enum.
 		</constant>
 		<constant name="DIFFUSE_BURLEY" value="0" enum="DiffuseMode">

doc/classes/ProjectSettings.xml

@@ -3095,6 +3095,9 @@
 		<member name="rendering/reflections/sky_reflections/texture_array_reflections.mobile" type="bool" setter="" getter="" default="false">
 			Lower-end override for [member rendering/reflections/sky_reflections/texture_array_reflections] on mobile devices, due to performance concerns or driver support.
 		</member>
+		<member name="rendering/reflections/specular_occlusion/enabled" type="bool" setter="" getter="" default="true">
+			If [code]true[/code], reduces reflections based on ambient light.
+		</member>
 		<member name="rendering/renderer/rendering_method" type="String" setter="" getter="" default="&quot;forward_plus&quot;">
 			Sets the renderer that will be used by the project. Options are:
 			[b]forward_plus[/b] (Forward+): High-end renderer designed for desktop devices. Has a higher base overhead, but scales well with complex scenes. Not suitable for older devices or mobile.

drivers/gles3/rasterizer_scene_gles3.cpp

@@ -4225,6 +4225,9 @@ RasterizerSceneGLES3::RasterizerSceneGLES3() {
 		if (config->force_vertex_shading) {
 			global_defines += "\n#define USE_VERTEX_LIGHTING\n";
 		}
+		if (!config->specular_occlusion) {
+			global_defines += "\n#define SPECULAR_OCCLUSION_DISABLED\n";
+		}
 		material_storage->shaders.scene_shader.initialize(global_defines);
 		scene_globals.shader_default_version = material_storage->shaders.scene_shader.version_create();
 		material_storage->shaders.scene_shader.version_bind_shader(scene_globals.shader_default_version, SceneShaderGLES3::MODE_COLOR);

drivers/gles3/shaders/scene.glsl

@@ -2120,8 +2120,18 @@ void main() {
 #endif // USE_LIGHTMAP_CAPTURE
 #endif // !DISABLE_LIGHTMAP
 
-	ambient_light *= albedo.rgb;
 	ambient_light *= ao;
+#ifndef SPECULAR_OCCLUSION_DISABLED
+	float specular_occlusion = (ambient_light.r * 0.3 + ambient_light.g * 0.59 + ambient_light.b * 0.11) * 2.0; // Luminance of ambient light.
+	specular_occlusion = min(specular_occlusion * 4.0, 1.0); // This multiplication preserves speculars on bright areas.
+
+	float reflective_f = (1.0 - roughness) * metallic;
+	// 10.0 is a magic number, it gives the intended effect in most scenarios.
+	// Low enough for occlusion, high enough for reaction to lights and shadows.
+	specular_occlusion = max(min(reflective_f * specular_occlusion * 10.0, 1.0), specular_occlusion);
+	specular_light *= specular_occlusion;
+#endif // !SPECULAR_OCCLUSION_DISABLED
+	ambient_light *= albedo.rgb;
 
 #endif // !AMBIENT_LIGHT_DISABLED
 

drivers/gles3/storage/config.cpp

@@ -185,6 +185,7 @@ Config::Config() {
 #endif
 
 	force_vertex_shading = GLOBAL_GET("rendering/shading/overrides/force_vertex_shading");
+	specular_occlusion = GLOBAL_GET("rendering/reflections/specular_occlusion/enabled");
 	use_nearest_mip_filter = GLOBAL_GET("rendering/textures/default_filters/use_nearest_mipmap_filter");
 
 	use_depth_prepass = bool(GLOBAL_GET("rendering/driver/depth_prepass/enable"));

drivers/gles3/storage/config.h

@@ -83,6 +83,7 @@ public:
 	bool srgb_framebuffer_supported = false;
 
 	bool force_vertex_shading = false;
+	bool specular_occlusion = false;
 
 	bool support_anisotropic_filter = false;
 	float anisotropic_level = 0.0f;

drivers/gles3/storage/material_storage.cpp

@@ -1382,6 +1382,8 @@ MaterialStorage::MaterialStorage() {
 		}
 		actions.render_mode_defines["fog_disabled"] = "#define FOG_DISABLED\n";
 
+		actions.render_mode_defines["specular_occlusion_disabled"] = "#define SPECULAR_OCCLUSION_DISABLED\n";
+
 		actions.default_filter = ShaderLanguage::FILTER_LINEAR_MIPMAP;
 		actions.default_repeat = ShaderLanguage::REPEAT_ENABLE;
 

scene/resources/material.cpp

@@ -873,7 +873,9 @@ void BaseMaterial3D::_update_shader() {
 	if (flags[FLAG_DISABLE_FOG]) {
 		code += ", fog_disabled";
 	}
-
+	if (flags[FLAG_DISABLE_SPECULAR_OCCLUSION]) {
+		code += ", specular_occlusion_disabled";
+	}
 	if (transparency == TRANSPARENCY_ALPHA_DEPTH_PRE_PASS) {
 		code += ", depth_prepass_alpha";
 	}
@@ -3208,6 +3210,7 @@ void BaseMaterial3D::_bind_methods() {
 	ADD_PROPERTY(PropertyInfo(Variant::INT, "specular_mode", PROPERTY_HINT_ENUM, "SchlickGGX,Toon,Disabled"), "set_specular_mode", "get_specular_mode");
 	ADD_PROPERTYI(PropertyInfo(Variant::BOOL, "disable_ambient_light"), "set_flag", "get_flag", FLAG_DISABLE_AMBIENT_LIGHT);
 	ADD_PROPERTYI(PropertyInfo(Variant::BOOL, "disable_fog"), "set_flag", "get_flag", FLAG_DISABLE_FOG);
+	ADD_PROPERTYI(PropertyInfo(Variant::BOOL, "disable_specular_occlusion"), "set_flag", "get_flag", FLAG_DISABLE_SPECULAR_OCCLUSION);
 
 	ADD_GROUP("Vertex Color", "vertex_color");
 	ADD_PROPERTYI(PropertyInfo(Variant::BOOL, "vertex_color_use_as_albedo"), "set_flag", "get_flag", FLAG_ALBEDO_FROM_VERTEX_COLOR);
@@ -3466,6 +3469,7 @@ void BaseMaterial3D::_bind_methods() {
 	BIND_ENUM_CONSTANT(FLAG_PARTICLE_TRAILS_MODE);
 	BIND_ENUM_CONSTANT(FLAG_ALBEDO_TEXTURE_MSDF);
 	BIND_ENUM_CONSTANT(FLAG_DISABLE_FOG);
+	BIND_ENUM_CONSTANT(FLAG_DISABLE_SPECULAR_OCCLUSION);
 	BIND_ENUM_CONSTANT(FLAG_MAX);
 
 	BIND_ENUM_CONSTANT(DIFFUSE_BURLEY);

scene/resources/material.h

@@ -267,6 +267,7 @@ public:
 		FLAG_PARTICLE_TRAILS_MODE,
 		FLAG_ALBEDO_TEXTURE_MSDF,
 		FLAG_DISABLE_FOG,
+		FLAG_DISABLE_SPECULAR_OCCLUSION,
 		FLAG_MAX
 	};
 

servers/rendering/renderer_rd/forward_clustered/render_forward_clustered.cpp

@@ -4872,6 +4872,11 @@ RenderForwardClustered::RenderForwardClustered() {
 			defines += "\n#define USE_VERTEX_LIGHTING\n";
 		}
 
+		bool specular_occlusion = GLOBAL_GET("rendering/reflections/specular_occlusion/enabled");
+		if (!specular_occlusion) {
+			defines += "\n#define SPECULAR_OCCLUSION_DISABLED\n";
+		}
+
 		{
 			//lightmaps
 			scene_state.max_lightmaps = MAX_LIGHTMAPS;

servers/rendering/renderer_rd/forward_clustered/scene_shader_forward_clustered.cpp

@@ -766,6 +766,8 @@ void SceneShaderForwardClustered::init(const String p_defines) {
 		actions.render_mode_defines["debug_shadow_splits"] = "#define DEBUG_DRAW_PSSM_SPLITS\n";
 		actions.render_mode_defines["fog_disabled"] = "#define FOG_DISABLED\n";
 
+		actions.render_mode_defines["specular_occlusion_disabled"] = "#define SPECULAR_OCCLUSION_DISABLED\n";
+
 		actions.base_texture_binding_index = 1;
 		actions.texture_layout_set = RenderForwardClustered::MATERIAL_UNIFORM_SET;
 		actions.base_uniform_string = "material.";

servers/rendering/renderer_rd/forward_mobile/render_forward_mobile.cpp

@@ -3221,6 +3221,11 @@ RenderForwardMobile::RenderForwardMobile() {
 		defines += "\n#define USE_VERTEX_LIGHTING\n";
 	}
 
+	bool specular_occlusion = GLOBAL_GET("rendering/reflections/specular_occlusion/enabled");
+	if (!specular_occlusion) {
+		defines += "\n#define SPECULAR_OCCLUSION_DISABLED\n";
+	}
+
 	{
 		//lightmaps
 		scene_state.max_lightmaps = 2;

servers/rendering/renderer_rd/forward_mobile/scene_shader_forward_mobile.cpp

@@ -698,6 +698,8 @@ void SceneShaderForwardMobile::init(const String p_defines) {
 		actions.render_mode_defines["debug_shadow_splits"] = "#define DEBUG_DRAW_PSSM_SPLITS\n";
 		actions.render_mode_defines["fog_disabled"] = "#define FOG_DISABLED\n";
 
+		actions.render_mode_defines["specular_occlusion_disabled"] = "#define SPECULAR_OCCLUSION_DISABLED\n";
+
 		actions.base_texture_binding_index = 1;
 		actions.texture_layout_set = RenderForwardMobile::MATERIAL_UNIFORM_SET;
 		actions.base_uniform_string = "material.";

servers/rendering/renderer_rd/shaders/forward_clustered/scene_forward_clustered.glsl

@@ -1969,8 +1969,18 @@ void fragment_shader(in SceneData scene_data) {
 
 	//finalize ambient light here
 	{
-		ambient_light *= albedo.rgb;
 		ambient_light *= ao;
+#ifndef SPECULAR_OCCLUSION_DISABLED
+		float specular_occlusion = (ambient_light.r * 0.3 + ambient_light.g * 0.59 + ambient_light.b * 0.11) * 2.0; // Luminance of ambient light.
+		specular_occlusion = min(specular_occlusion * 4.0, 1.0); // This multiplication preserves speculars on bright areas.
+
+		float reflective_f = (1.0 - roughness) * metallic;
+		// 10.0 is a magic number, it gives the intended effect in most scenarios.
+		// Low enough for occlusion, high enough for reaction to lights and shadows.
+		specular_occlusion = max(min(reflective_f * specular_occlusion * 10.0, 1.0), specular_occlusion);
+		specular_light *= specular_occlusion;
+#endif // SPECULAR_OCCLUSION_DISABLED
+		ambient_light *= albedo.rgb;
 
 		if (bool(implementation_data.ss_effects_flags & SCREEN_SPACE_EFFECTS_FLAGS_USE_SSIL)) {
 #ifdef USE_MULTIVIEW

servers/rendering/renderer_rd/shaders/forward_mobile/scene_forward_mobile.glsl

@@ -1437,9 +1437,18 @@ void main() {
 	} //Reflection probes
 
 	// finalize ambient light here
-
-	ambient_light *= albedo.rgb;
 	ambient_light *= ao;
+#ifndef SPECULAR_OCCLUSION_DISABLED
+	float specular_occlusion = (ambient_light.r * 0.3 + ambient_light.g * 0.59 + ambient_light.b * 0.11) * 2.0; // Luminance of ambient light.
+	specular_occlusion = min(specular_occlusion * 4.0, 1.0); // This multiplication preserves speculars on bright areas.
+
+	float reflective_f = (1.0 - roughness) * metallic;
+	// 10.0 is a magic number, it gives the intended effect in most scenarios.
+	// Low enough for occlusion, high enough for reaction to lights and shadows.
+	specular_occlusion = max(min(reflective_f * specular_occlusion * 10.0, 1.0), specular_occlusion);
+	specular_light *= specular_occlusion;
+#endif // USE_SPECULAR_OCCLUSION
+	ambient_light *= albedo.rgb;
 
 #endif // !AMBIENT_LIGHT_DISABLED
 

servers/rendering/shader_types.cpp

@@ -242,6 +242,7 @@ ShaderTypes::ShaderTypes() {
 		shader_modes[RS::SHADER_SPATIAL].modes.push_back({ PNAME("alpha_to_coverage_and_one") });
 		shader_modes[RS::SHADER_SPATIAL].modes.push_back({ PNAME("debug_shadow_splits") });
 		shader_modes[RS::SHADER_SPATIAL].modes.push_back({ PNAME("fog_disabled") });
+		shader_modes[RS::SHADER_SPATIAL].modes.push_back({ PNAME("specular_occlusion_disabled") });
 	}
 
 	/************ CANVAS ITEM **************************/

servers/rendering_server.cpp

@@ -3632,6 +3632,7 @@ void RenderingServer::init() {
 	GLOBAL_DEF(PropertyInfo(Variant::INT, "rendering/reflections/reflection_atlas/reflection_size", PROPERTY_HINT_RANGE, "0,4096,1"), 256);
 	GLOBAL_DEF(PropertyInfo(Variant::INT, "rendering/reflections/reflection_atlas/reflection_size.mobile", PROPERTY_HINT_RANGE, "0,2048,1"), 128);
 	GLOBAL_DEF(PropertyInfo(Variant::INT, "rendering/reflections/reflection_atlas/reflection_count", PROPERTY_HINT_RANGE, "0,256,1"), 64);
+	GLOBAL_DEF_RST("rendering/reflections/specular_occlusion/enabled", true);
 
 	GLOBAL_DEF("rendering/global_illumination/gi/use_half_resolution", false);