Add support for BPTC and RGTC compressed texture extensions

Author: lojjic

src/texture-utils.js

@@ -269,6 +269,16 @@ const COMPRESSED_SRGB_S3TC_DXT1_EXT        = 0x8C4C;
 const COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT  = 0x8C4D;
 const COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT  = 0x8C4E;
 const COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT  = 0x8C4F;
+// EXT_texture_compression_bptc
+const COMPRESSED_RGBA_BPTC_UNORM_EXT = 0x8E8C;
+const COMPRESSED_SRGB_ALPHA_BPTC_UNORM_EXT = 0x8E8D;
+const COMPRESSED_RGB_BPTC_SIGNED_FLOAT_EXT = 0x8E8E;
+const COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_EXT = 0x8E8F;
+// EXT_texture_compression_rgtc
+const COMPRESSED_RED_RGTC1_EXT = 0x8DBB;
+const COMPRESSED_SIGNED_RED_RGTC1_EXT = 0x8DBC;
+const COMPRESSED_RED_GREEN_RGTC2_EXT = 0x8DBD;
+const COMPRESSED_SIGNED_RED_GREEN_RGTC2_EXT = 0x8DBE;
 
 const compressedTextureFunctions = new Map([
   [ COMPRESSED_RGB_S3TC_DXT1_EXT, makeComputeBlockRectSizeFunction(4, 4, 8) ],
@@ -328,6 +338,16 @@ const compressedTextureFunctions = new Map([
   [ COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT, makeComputeBlockRectSizeFunction(4, 4, 8) ],
   [ COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT, makeComputeBlockRectSizeFunction(4, 4, 16) ],
   [ COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT, makeComputeBlockRectSizeFunction(4, 4, 16) ],
+
+  [ COMPRESSED_RGBA_BPTC_UNORM_EXT, makeComputeBlockRectSizeFunction( 4, 4, 16 ) ],
+  [ COMPRESSED_SRGB_ALPHA_BPTC_UNORM_EXT, makeComputeBlockRectSizeFunction( 4, 4, 16 ) ],
+  [ COMPRESSED_RGB_BPTC_SIGNED_FLOAT_EXT, makeComputeBlockRectSizeFunction( 4, 4, 16 ) ],
+  [ COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_EXT, makeComputeBlockRectSizeFunction( 4, 4, 16 ) ],
+
+  [ COMPRESSED_RED_RGTC1_EXT, makeComputeBlockRectSizeFunction( 4, 4, 8 ) ],
+  [ COMPRESSED_SIGNED_RED_RGTC1_EXT, makeComputeBlockRectSizeFunction( 4, 4, 8 ) ],
+  [ COMPRESSED_RED_GREEN_RGTC2_EXT, makeComputeBlockRectSizeFunction( 4, 4, 16 ) ],
+  [ COMPRESSED_SIGNED_RED_GREEN_RGTC2_EXT, makeComputeBlockRectSizeFunction( 4, 4, 16 ) ],
 ]);
 
 /**