Adding support for Specular-AA

jme3-core/src/main/java/com/jme3/texture/Texture.java

@@ -637,11 +637,11 @@ public void read(JmeImporter importer) throws IOException {
             }
         }
 
-        anisotropicFilter = capsule.readInt("anisotropicFilter", 1);
-        minificationFilter = capsule.readEnum("minificationFilter",
+        setAnisotropicFilter(capsule.readInt("anisotropicFilter", 1));
+        setMinFilter(capsule.readEnum("minificationFilter",
                 MinFilter.class,
-                MinFilter.BilinearNoMipMaps);
-        magnificationFilter = capsule.readEnum("magnificationFilter",
-                MagFilter.class, MagFilter.Bilinear);
+                MinFilter.BilinearNoMipMaps));
+        setMagFilter(capsule.readEnum("magnificationFilter",
+                MagFilter.class, MagFilter.Bilinear));
     }
 }

jme3-core/src/main/resources/Common/MatDefs/Light/PBRLighting.j3md

@@ -56,6 +56,9 @@ MaterialDef PBR Lighting {
         // Parallax/height map
         Texture2D ParallaxMap -LINEAR
 
+        // Specular-AA
+        Boolean SpecularAA
+
         //Set to true if parallax map is stored in the alpha channel of the normal map
         Boolean PackedNormalParallax   
 
@@ -163,6 +166,7 @@ MaterialDef PBR Lighting {
             USE_PACKED_MR: MetallicRoughnessMap
             USE_PACKED_SG: SpecularGlossinessMap
             SPECULARMAP : SpecularMap
+            SPECULAR_AA : SpecularAA
             GLOSSINESSMAP : GlossinessMap
             NORMAL_TYPE: NormalType
             VERTEX_COLOR : UseVertexColor

jme3-core/src/main/resources/Common/ShaderLib/PBR.glsllib

@@ -6,6 +6,24 @@
     #define NB_PROBES 0
 #endif
 
+// BEGIN-@jhonkkk,Specular AA --------------------------------------------------------------
+// see:http://www.jp.square-enix.com/tech/library/pdf/ImprovedGeometricSpecularAA(slides).pdf
+// https://docs.unity3d.com/Packages/com.unity.render-pipelines.high-definition@15.0/manual/Geometric-Specular-Anti-Aliasing.html
+void Specular_Anti_Aliasing(in vec3 normal, in vec3 half_vector,
+                           	inout float alpha_x)
+{
+
+    float sigma = 0.50f; 							//- screen space variance
+    float Kappa = 0.18f;								//- clamping treshold
+    vec3 dndu = dFdx(normal);
+    vec3 dndv = dFdy(normal);
+    float  variance = sigma*sigma*(dot(dndu, dndu) + dot(dndv, dndv));
+    float  kernel_roughness = min(Kappa, variance);
+    alpha_x = sqrt(alpha_x*alpha_x + kernel_roughness);
+}
+// END-@jhonkkk
+
+
 //Specular fresnel computation
 vec3 F_Shlick(float vh,	vec3 F0){
 	float fresnelFact = pow(2.0, (-5.55473*vh - 6.98316) * vh);
@@ -54,6 +72,9 @@ float PBR_ComputeDirectLight(vec3 normal, vec3 lightDir, vec3 viewDir,
     //cook-torrence, microfacet BRDF : http://blog.selfshadow.com/publications/s2013-shading-course/karis/s2013_pbs_epic_notes_v2.pdf
 
     float alpha = roughness * roughness;
+    #ifdef SPECULAR_AA
+        Specular_Anti_Aliasing(normal, halfVec, alpha);
+    #endif
 
     //D, GGX normal Distribution function
     float alpha2 = alpha * alpha;