switch from define for texture size to a float const.

src/renderers/shaders/ShaderChunk/cube_uv_reflection_fragment.glsl

@@ -2,7 +2,7 @@
 
 #ifdef ENVMAP_TYPE_CUBE_UV
 
-#define CUBE_UV_TEXTURE_SIZE 1024
+const float cubeUV_textureSize = 1024.0;
 
 int getFaceFromDirection(vec3 direction) {
     vec3 absDirection = abs(direction);
@@ -21,7 +21,7 @@ int getFaceFromDirection(vec3 direction) {
     }
     return face;
 }
-const float cubeUV_maxLods1 = log2(float(CUBE_UV_TEXTURE_SIZE)*0.25) - 1.0;
+const float cubeUV_maxLods1 = log2(cubeUV_textureSize*0.25) - 1.0;
 const float cubeUV_rangeClamp = exp2((6.0 - 1.0) * 2.0);
 
 vec2 MipLevelInfo( vec3 vec, float roughnessLevel, float roughness ) {
@@ -37,8 +37,8 @@ vec2 MipLevelInfo( vec3 vec, float roughnessLevel, float roughness ) {
     return vec2(floor(mipLevel), fract(mipLevel));
 }
 
-const float cubeUV_maxLods2 = log2(float(CUBE_UV_TEXTURE_SIZE)*0.25) - 2.0;
-const float cubeUV_rcpTextureSize = 1.0 / float(CUBE_UV_TEXTURE_SIZE);
+const float cubeUV_maxLods2 = log2(cubeUV_textureSize*0.25) - 2.0;
+const float cubeUV_rcpTextureSize = 1.0 / cubeUV_textureSize;
 
 vec2 getCubeUV(vec3 direction, float roughnessLevel, float mipLevel) {
     mipLevel = roughnessLevel > cubeUV_maxLods2 - 3.0 ? 0.0 : mipLevel;
@@ -99,7 +99,7 @@ vec2 getCubeUV(vec3 direction, float roughnessLevel, float mipLevel) {
     return base + s * ( scale - 2.0 * texelOffset );
 }
 
-const float cubeUV_maxLods3 = log2(float(CUBE_UV_TEXTURE_SIZE)*0.25) - 3.0;
+const float cubeUV_maxLods3 = log2(cubeUV_textureSize*0.25) - 3.0;
 
 vec4 textureCubeUV(vec3 reflectedDirection, float roughness ) {
     float roughnessVal = roughness* cubeUV_maxLods3;