Adding entry for EXT_sRGB's unsized RGBA type

This type is now the default for certain textures in three.js's webgl1 fallback

Author: dmtaub

src/texture-utils.js

@@ -90,6 +90,9 @@ const RED_INTEGER                  = 0x8D94;
 const RGB_INTEGER                  = 0x8D98;
 const RGBA_INTEGER                 = 0x8D99;
 
+const SRGB_ALPHA_EXT               = 0x8C42;
+
+
 const formatInfo = {};
 {
   // NOTE: this is named `numColorComponents` vs `numComponents` so we can let Uglify mangle
@@ -133,6 +136,7 @@ function getTextureInternalFormatInfo(internalFormat) {
     t[LUMINANCE_ALPHA]    = { bytesPerElement: [2, 4, 4, 8],        type: [UNSIGNED_BYTE, HALF_FLOAT, HALF_FLOAT_OES, FLOAT], };
     t[RGB]                = { bytesPerElement: [3, 6, 6, 12, 2],    type: [UNSIGNED_BYTE, HALF_FLOAT, HALF_FLOAT_OES, FLOAT, UNSIGNED_SHORT_5_6_5], };
     t[RGBA]               = { bytesPerElement: [4, 8, 8, 16, 2, 2], type: [UNSIGNED_BYTE, HALF_FLOAT, HALF_FLOAT_OES, FLOAT, UNSIGNED_SHORT_4_4_4_4, UNSIGNED_SHORT_5_5_5_1], };
+    t[SRGB_ALPHA_EXT]     = { bytesPerElement: [4, 8, 8, 16, 2, 2], type: [UNSIGNED_BYTE, HALF_FLOAT, HALF_FLOAT_OES, FLOAT, UNSIGNED_SHORT_4_4_4_4, UNSIGNED_SHORT_5_5_5_1], };
     t[DEPTH_COMPONENT]    = { bytesPerElement: [2, 4],              type: [UNSIGNED_INT, UNSIGNED_SHORT], };
     t[DEPTH_STENCIL]      = { bytesPerElement: [4],                 };
 
@@ -380,4 +384,4 @@ function getBytesForMipUncompressed(internalFormat, width, height, depth, type)
 export function getBytesForMip(internalFormat, width, height, depth, type) {
   const fn = compressedTextureFunctions.get(internalFormat);
   return fn ? fn(width, height, depth) : getBytesForMipUncompressed(internalFormat, width, height, depth, type);
-};
+};