enable WebGL1 compatibility

src/Materials/PBR/pbrBaseMaterial.ts

@@ -1327,7 +1327,11 @@ export abstract class PBRBaseMaterial extends PushMaterial {
                     defines.LINEARSPECULARREFLECTION = reflectionTexture.linearSpecularLOD;
 
                     if (this.realTimeFiltering && this.realTimeFilteringQuality > 0) {
-                        defines.NUM_SAMPLES = this.realTimeFilteringQuality + "u";
+                        defines.NUM_SAMPLES = "" + this.realTimeFilteringQuality;
+                        if (engine.webGLVersion > 1) {
+                            defines.NUM_SAMPLES = defines.NUM_SAMPLES + "u";
+                        }
+
                         defines.REALTIME_FILTERING = true;
                     } else {
                         defines.REALTIME_FILTERING = false;

src/Shaders/ShadersInclude/hdrFilteringFunctions.fx

@@ -1,5 +1,10 @@
-#if defined(WEBGL2) && defined(NUM_SAMPLES)
-	#if NUM_SAMPLES > 0u
+#ifdef NUM_SAMPLES
+	#ifdef WEBGL2
+		#define ZERO 0u
+	#else
+		#define ZERO 0
+	#endif
+	#if NUM_SAMPLES > ZERO
 		const float NUM_SAMPLES_FLOAT = float(NUM_SAMPLES);
 		const float NUM_SAMPLES_FLOAT_INVERSED = 1. / NUM_SAMPLES_FLOAT;
 
@@ -133,7 +138,11 @@
 		    float dim0 = filteringInfo.x;
 		    float omegaP = (4. * PI) / (6. * dim0 * dim0);
 
+		    #ifdef WEBGL2
 		    for(uint i = 0u; i < NUM_SAMPLES; ++i)
+		    #else
+		    for(int i = 0; i < NUM_SAMPLES; ++i)
+		    #endif
 		    {
 		        vec2 Xi = hammersley(i, NUM_SAMPLES);
 		        vec3 Ls = hemisphereCosSample(Xi);
@@ -186,7 +195,11 @@
 			float omegaP = (4. * PI) / (6. * dim0 * dim0);
 
 			float weight = 0.;
+			#ifdef WEBGL2
 			for(uint i = 0u; i < NUM_SAMPLES; ++i)
+			#else
+			for(int i = 0; i < NUM_SAMPLES; ++i)
+			#endif
 			{
 			    vec2 Xi = hammersley(i, NUM_SAMPLES);
 			    vec3 H = hemisphereImportanceSampleDggx(Xi, alphaG);

src/Shaders/ShadersInclude/helperFunctions.fx

@@ -91,30 +91,30 @@ float square(float value)
         return vec2(float(i)/float(N), radicalInverse_VdC(i));
     }
 #else
-    // float vanDerCorpus(uint n, uint base)
-    // {
-    //     float invBase = 1.0 / float(base);
-    //     float denom   = 1.0;
-    //     float result  = 0.0;
-
-    //     for(uint i = 0u; i < 32u; ++i)
-    //     {
-    //         if(n > 0u)
-    //         {
-    //             denom   = mod(float(n), 2.0);
-    //             result += denom * invBase;
-    //             invBase = invBase / 2.0;
-    //             n       = uint(float(n) / 2.0);
-    //         }
-    //     }
-
-    //     return result;
-    // }
-
-    // vec2 hammersley(uint i, uint N)
-    // {
-    //     return vec2(float(i)/float(N), vanDerCorpus(i, 2u));
-    // }
+    float vanDerCorpus(int n, int base)
+    {
+        float invBase = 1.0 / float(base);
+        float denom   = 1.0;
+        float result  = 0.0;
+
+        for(int i = 0; i < 32; ++i)
+        {
+            if(n > 0)
+            {
+                denom   = mod(float(n), 2.0);
+                result += denom * invBase;
+                invBase = invBase / 2.0;
+                n       = int(float(n) / 2.0);
+            }
+        }
+
+        return result;
+    }
+
+    vec2 hammersley(int i, int N)
+    {
+        return vec2(float(i)/float(N), vanDerCorpus(i, 2));
+    }
 #endif
 
 float log4(float x) {

src/Shaders/ShadersInclude/pbrFragmentDeclaration.fx

@@ -53,7 +53,7 @@ uniform mat4 view;
 #ifdef REFLECTION
     uniform vec2 vReflectionInfos;
     #ifdef REALTIME_FILTERING
-        uniform vec2 vReflectionFilteringInfo
+        uniform vec2 vReflectionFilteringInfo;
     #endif
     uniform mat4 reflectionMatrix;
     uniform vec3 vReflectionMicrosurfaceInfos;