Add ambient texture strength on PBR

src/Materials/babylon.pbrMaterial.ts

@@ -261,6 +261,12 @@
         @serializeAsTexture()
         public ambientTexture: BaseTexture;
 
+        /**
+         * AKA Occlusion Texture Intensity in other nomenclature.
+         */
+        @serialize()
+        public ambientTextureStrength: number = 1.0;
+
         @serializeAsTexture()
         public opacityTexture: BaseTexture;
 
@@ -1108,7 +1114,7 @@
                     if (this.ambientTexture && StandardMaterial.AmbientTextureEnabled) {
                         this._effect.setTexture("ambientSampler", this.ambientTexture);
 
-                        this._effect.setFloat2("vAmbientInfos", this.ambientTexture.coordinatesIndex, this.ambientTexture.level);
+                        this._effect.setFloat3("vAmbientInfos", this.ambientTexture.coordinatesIndex, this.ambientTexture.level, this.ambientTextureStrength);
                         this._effect.setMatrix("ambientMatrix", this.ambientTexture.getTextureMatrix());
                     }
 

src/Shaders/legacypbr.fragment.fx

@@ -54,7 +54,7 @@ uniform vec2 vAlbedoInfos;
 #ifdef AMBIENT
 varying vec2 vAmbientUV;
 uniform sampler2D ambientSampler;
-uniform vec2 vAmbientInfos;
+uniform vec3 vAmbientInfos;
 #endif
 
 #ifdef OPACITY	
@@ -146,6 +146,7 @@ void main(void) {
 
     #ifdef AMBIENT
         ambientColor = texture2D(ambientSampler, vAmbientUV).rgb * vAmbientInfos.y;
+        ambientColor = vec3(1., 1., 1.) - ((vec3(1., 1., 1.) - ambientColor) * vAmbientInfos.z);
         
         #ifdef OVERLOADEDVALUES
             ambientColor.rgb = mix(ambientColor.rgb, vOverloadedAmbient, vOverloadedIntensity.x);

src/Shaders/legacypbr.vertex.fx

@@ -28,7 +28,7 @@ uniform vec2 vAlbedoInfos;
 #ifdef AMBIENT
 varying vec2 vAmbientUV;
 uniform mat4 ambientMatrix;
-uniform vec2 vAmbientInfos;
+uniform vec3 vAmbientInfos;
 #endif
 
 #ifdef OPACITY

src/Shaders/pbr.fragment.fx

@@ -66,7 +66,7 @@ uniform vec2 vAlbedoInfos;
 #ifdef AMBIENT
 varying vec2 vAmbientUV;
 uniform sampler2D ambientSampler;
-uniform vec2 vAmbientInfos;
+uniform vec3 vAmbientInfos;
 #endif
 
 #ifdef OPACITY	
@@ -234,6 +234,7 @@ void main(void) {
 
 #ifdef AMBIENT
 	ambientColor = texture2D(ambientSampler, vAmbientUV).rgb * vAmbientInfos.y;
+	ambientColor = vec3(1., 1., 1.) - ((vec3(1., 1., 1.) - ambientColor) * vAmbientInfos.z);
 
 #ifdef OVERLOADEDVALUES
 	ambientColor.rgb = mix(ambientColor.rgb, vOverloadedAmbient, vOverloadedIntensity.x);

src/Shaders/pbr.vertex.fx

@@ -32,7 +32,7 @@ uniform vec2 vAlbedoInfos;
 #ifdef AMBIENT
 varying vec2 vAmbientUV;
 uniform mat4 ambientMatrix;
-uniform vec2 vAmbientInfos;
+uniform vec3 vAmbientInfos;
 #endif
 
 #ifdef OPACITY