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📄 WebGLUtils.js

📊 Analysis Summary

Metric Count
🔧 Functions 2
📦 Imports 57
📊 Variables & Constants 1

📚 Table of Contents

🛠️ File Location:

📂 src/renderers/webgl/WebGLUtils.js

📦 Imports

Name Source
RGBA_ASTC_4x4_Format ../../constants.js
RGBA_ASTC_5x4_Format ../../constants.js
RGBA_ASTC_5x5_Format ../../constants.js
RGBA_ASTC_6x5_Format ../../constants.js
RGBA_ASTC_6x6_Format ../../constants.js
RGBA_ASTC_8x5_Format ../../constants.js
RGBA_ASTC_8x6_Format ../../constants.js
RGBA_ASTC_8x8_Format ../../constants.js
RGBA_ASTC_10x5_Format ../../constants.js
RGBA_ASTC_10x6_Format ../../constants.js
RGBA_ASTC_10x8_Format ../../constants.js
RGBA_ASTC_10x10_Format ../../constants.js
RGBA_ASTC_12x10_Format ../../constants.js
RGBA_ASTC_12x12_Format ../../constants.js
RGB_ETC1_Format ../../constants.js
RGB_ETC2_Format ../../constants.js
RGBA_ETC2_EAC_Format ../../constants.js
RGBA_PVRTC_2BPPV1_Format ../../constants.js
RGBA_PVRTC_4BPPV1_Format ../../constants.js
RGB_PVRTC_2BPPV1_Format ../../constants.js
RGB_PVRTC_4BPPV1_Format ../../constants.js
RGBA_S3TC_DXT5_Format ../../constants.js
RGBA_S3TC_DXT3_Format ../../constants.js
RGBA_S3TC_DXT1_Format ../../constants.js
RGB_S3TC_DXT1_Format ../../constants.js
DepthFormat ../../constants.js
DepthStencilFormat ../../constants.js
RedFormat ../../constants.js
RGBAFormat ../../constants.js
AlphaFormat ../../constants.js
RedIntegerFormat ../../constants.js
RGFormat ../../constants.js
RGIntegerFormat ../../constants.js
RGBAIntegerFormat ../../constants.js
HalfFloatType ../../constants.js
FloatType ../../constants.js
UnsignedIntType ../../constants.js
IntType ../../constants.js
UnsignedShortType ../../constants.js
ShortType ../../constants.js
ByteType ../../constants.js
UnsignedInt248Type ../../constants.js
UnsignedShort5551Type ../../constants.js
UnsignedShort4444Type ../../constants.js
UnsignedByteType ../../constants.js
RGBA_BPTC_Format ../../constants.js
RGB_BPTC_SIGNED_Format ../../constants.js
RGB_BPTC_UNSIGNED_Format ../../constants.js
RED_RGTC1_Format ../../constants.js
SIGNED_RED_RGTC1_Format ../../constants.js
RED_GREEN_RGTC2_Format ../../constants.js
SIGNED_RED_GREEN_RGTC2_Format ../../constants.js
NoColorSpace ../../constants.js
SRGBTransfer ../../constants.js
UnsignedInt5999Type ../../constants.js
RGBFormat ../../constants.js
ColorManagement ../../math/ColorManagement.js

Variables & Constants

Name Type Kind Value Exported
extension any let/var *not shown*

Functions

WebGLUtils(gl: any, extensions: any): { convert: (p: any, colorSpace?: string) => any; }

Parameters:

  • gl any
  • extensions any

Returns: { convert: (p: any, colorSpace?: string) => any; }

Calls:

  • ColorManagement.getTransfer
  • extensions.get

Internal Comments:

// WebGL2 formats.
// S3TC
// PVRTC
// ETC
// ASTC
// BPTC
// RGTC
//
// if "p" can't be resolved, assume the user defines a WebGL constant as a string (fallback/workaround for packed RGB formats)

Code
function WebGLUtils( gl, extensions ) {

    function convert( p, colorSpace = NoColorSpace ) {

        let extension;

        const transfer = ColorManagement.getTransfer( colorSpace );

        if ( p === UnsignedByteType ) return gl.UNSIGNED_BYTE;
        if ( p === UnsignedShort4444Type ) return gl.UNSIGNED_SHORT_4_4_4_4;
        if ( p === UnsignedShort5551Type ) return gl.UNSIGNED_SHORT_5_5_5_1;
        if ( p === UnsignedInt5999Type ) return gl.UNSIGNED_INT_5_9_9_9_REV;

        if ( p === ByteType ) return gl.BYTE;
        if ( p === ShortType ) return gl.SHORT;
        if ( p === UnsignedShortType ) return gl.UNSIGNED_SHORT;
        if ( p === IntType ) return gl.INT;
        if ( p === UnsignedIntType ) return gl.UNSIGNED_INT;
        if ( p === FloatType ) return gl.FLOAT;
        if ( p === HalfFloatType ) return gl.HALF_FLOAT;

        if ( p === AlphaFormat ) return gl.ALPHA;
        if ( p === RGBFormat ) return gl.RGB;
        if ( p === RGBAFormat ) return gl.RGBA;
        if ( p === DepthFormat ) return gl.DEPTH_COMPONENT;
        if ( p === DepthStencilFormat ) return gl.DEPTH_STENCIL;

        // WebGL2 formats.

        if ( p === RedFormat ) return gl.RED;
        if ( p === RedIntegerFormat ) return gl.RED_INTEGER;
        if ( p === RGFormat ) return gl.RG;
        if ( p === RGIntegerFormat ) return gl.RG_INTEGER;
        if ( p === RGBAIntegerFormat ) return gl.RGBA_INTEGER;

        // S3TC

        if ( p === RGB_S3TC_DXT1_Format || p === RGBA_S3TC_DXT1_Format || p === RGBA_S3TC_DXT3_Format || p === RGBA_S3TC_DXT5_Format ) {

            if ( transfer === SRGBTransfer ) {

                extension = extensions.get( 'WEBGL_compressed_texture_s3tc_srgb' );

                if ( extension !== null ) {

                    if ( p === RGB_S3TC_DXT1_Format ) return extension.COMPRESSED_SRGB_S3TC_DXT1_EXT;
                    if ( p === RGBA_S3TC_DXT1_Format ) return extension.COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
                    if ( p === RGBA_S3TC_DXT3_Format ) return extension.COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
                    if ( p === RGBA_S3TC_DXT5_Format ) return extension.COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;

                } else {

                    return null;

                }

            } else {

                extension = extensions.get( 'WEBGL_compressed_texture_s3tc' );

                if ( extension !== null ) {

                    if ( p === RGB_S3TC_DXT1_Format ) return extension.COMPRESSED_RGB_S3TC_DXT1_EXT;
                    if ( p === RGBA_S3TC_DXT1_Format ) return extension.COMPRESSED_RGBA_S3TC_DXT1_EXT;
                    if ( p === RGBA_S3TC_DXT3_Format ) return extension.COMPRESSED_RGBA_S3TC_DXT3_EXT;
                    if ( p === RGBA_S3TC_DXT5_Format ) return extension.COMPRESSED_RGBA_S3TC_DXT5_EXT;

                } else {

                    return null;

                }

            }

        }

        // PVRTC

        if ( p === RGB_PVRTC_4BPPV1_Format || p === RGB_PVRTC_2BPPV1_Format || p === RGBA_PVRTC_4BPPV1_Format || p === RGBA_PVRTC_2BPPV1_Format ) {

            extension = extensions.get( 'WEBGL_compressed_texture_pvrtc' );

            if ( extension !== null ) {

                if ( p === RGB_PVRTC_4BPPV1_Format ) return extension.COMPRESSED_RGB_PVRTC_4BPPV1_IMG;
                if ( p === RGB_PVRTC_2BPPV1_Format ) return extension.COMPRESSED_RGB_PVRTC_2BPPV1_IMG;
                if ( p === RGBA_PVRTC_4BPPV1_Format ) return extension.COMPRESSED_RGBA_PVRTC_4BPPV1_IMG;
                if ( p === RGBA_PVRTC_2BPPV1_Format ) return extension.COMPRESSED_RGBA_PVRTC_2BPPV1_IMG;

            } else {

                return null;

            }

        }

        // ETC

        if ( p === RGB_ETC1_Format || p === RGB_ETC2_Format || p === RGBA_ETC2_EAC_Format ) {

            extension = extensions.get( 'WEBGL_compressed_texture_etc' );

            if ( extension !== null ) {

                if ( p === RGB_ETC1_Format || p === RGB_ETC2_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ETC2 : extension.COMPRESSED_RGB8_ETC2;
                if ( p === RGBA_ETC2_EAC_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ETC2_EAC : extension.COMPRESSED_RGBA8_ETC2_EAC;

            } else {

                return null;

            }

        }

        // ASTC

        if ( p === RGBA_ASTC_4x4_Format || p === RGBA_ASTC_5x4_Format || p === RGBA_ASTC_5x5_Format ||
            p === RGBA_ASTC_6x5_Format || p === RGBA_ASTC_6x6_Format || p === RGBA_ASTC_8x5_Format ||
            p === RGBA_ASTC_8x6_Format || p === RGBA_ASTC_8x8_Format || p === RGBA_ASTC_10x5_Format ||
            p === RGBA_ASTC_10x6_Format || p === RGBA_ASTC_10x8_Format || p === RGBA_ASTC_10x10_Format ||
            p === RGBA_ASTC_12x10_Format || p === RGBA_ASTC_12x12_Format ) {

            extension = extensions.get( 'WEBGL_compressed_texture_astc' );

            if ( extension !== null ) {

                if ( p === RGBA_ASTC_4x4_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_4x4_KHR : extension.COMPRESSED_RGBA_ASTC_4x4_KHR;
                if ( p === RGBA_ASTC_5x4_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_5x4_KHR : extension.COMPRESSED_RGBA_ASTC_5x4_KHR;
                if ( p === RGBA_ASTC_5x5_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_5x5_KHR : extension.COMPRESSED_RGBA_ASTC_5x5_KHR;
                if ( p === RGBA_ASTC_6x5_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_6x5_KHR : extension.COMPRESSED_RGBA_ASTC_6x5_KHR;
                if ( p === RGBA_ASTC_6x6_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_6x6_KHR : extension.COMPRESSED_RGBA_ASTC_6x6_KHR;
                if ( p === RGBA_ASTC_8x5_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_8x5_KHR : extension.COMPRESSED_RGBA_ASTC_8x5_KHR;
                if ( p === RGBA_ASTC_8x6_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_8x6_KHR : extension.COMPRESSED_RGBA_ASTC_8x6_KHR;
                if ( p === RGBA_ASTC_8x8_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_8x8_KHR : extension.COMPRESSED_RGBA_ASTC_8x8_KHR;
                if ( p === RGBA_ASTC_10x5_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_10x5_KHR : extension.COMPRESSED_RGBA_ASTC_10x5_KHR;
                if ( p === RGBA_ASTC_10x6_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR : extension.COMPRESSED_RGBA_ASTC_10x6_KHR;
                if ( p === RGBA_ASTC_10x8_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_10x8_KHR : extension.COMPRESSED_RGBA_ASTC_10x8_KHR;
                if ( p === RGBA_ASTC_10x10_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_10x10_KHR : extension.COMPRESSED_RGBA_ASTC_10x10_KHR;
                if ( p === RGBA_ASTC_12x10_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_12x10_KHR : extension.COMPRESSED_RGBA_ASTC_12x10_KHR;
                if ( p === RGBA_ASTC_12x12_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_12x12_KHR : extension.COMPRESSED_RGBA_ASTC_12x12_KHR;

            } else {

                return null;

            }

        }

        // BPTC

        if ( p === RGBA_BPTC_Format || p === RGB_BPTC_SIGNED_Format || p === RGB_BPTC_UNSIGNED_Format ) {

            extension = extensions.get( 'EXT_texture_compression_bptc' );

            if ( extension !== null ) {

                if ( p === RGBA_BPTC_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB_ALPHA_BPTC_UNORM_EXT : extension.COMPRESSED_RGBA_BPTC_UNORM_EXT;
                if ( p === RGB_BPTC_SIGNED_Format ) return extension.COMPRESSED_RGB_BPTC_SIGNED_FLOAT_EXT;
                if ( p === RGB_BPTC_UNSIGNED_Format ) return extension.COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_EXT;

            } else {

                return null;

            }

        }

        // RGTC

        if ( p === RED_RGTC1_Format || p === SIGNED_RED_RGTC1_Format || p === RED_GREEN_RGTC2_Format || p === SIGNED_RED_GREEN_RGTC2_Format ) {

            extension = extensions.get( 'EXT_texture_compression_rgtc' );

            if ( extension !== null ) {

                if ( p === RGBA_BPTC_Format ) return extension.COMPRESSED_RED_RGTC1_EXT;
                if ( p === SIGNED_RED_RGTC1_Format ) return extension.COMPRESSED_SIGNED_RED_RGTC1_EXT;
                if ( p === RED_GREEN_RGTC2_Format ) return extension.COMPRESSED_RED_GREEN_RGTC2_EXT;
                if ( p === SIGNED_RED_GREEN_RGTC2_Format ) return extension.COMPRESSED_SIGNED_RED_GREEN_RGTC2_EXT;

            } else {

                return null;

            }

        }

        //

        if ( p === UnsignedInt248Type ) return gl.UNSIGNED_INT_24_8;

        // if "p" can't be resolved, assume the user defines a WebGL constant as a string (fallback/workaround for packed RGB formats)

        return ( gl[ p ] !== undefined ) ? gl[ p ] : null;

    }

    return { convert: convert };

}

convert(p: any, colorSpace: string): any

Parameters:

  • p any
  • colorSpace string

Returns: any

Calls:

  • ColorManagement.getTransfer
  • extensions.get

Internal Comments:

// WebGL2 formats.
// S3TC
// PVRTC
// ETC
// ASTC
// BPTC
// RGTC
//
// if "p" can't be resolved, assume the user defines a WebGL constant as a string (fallback/workaround for packed RGB formats)

Code
function convert( p, colorSpace = NoColorSpace ) {

        let extension;

        const transfer = ColorManagement.getTransfer( colorSpace );

        if ( p === UnsignedByteType ) return gl.UNSIGNED_BYTE;
        if ( p === UnsignedShort4444Type ) return gl.UNSIGNED_SHORT_4_4_4_4;
        if ( p === UnsignedShort5551Type ) return gl.UNSIGNED_SHORT_5_5_5_1;
        if ( p === UnsignedInt5999Type ) return gl.UNSIGNED_INT_5_9_9_9_REV;

        if ( p === ByteType ) return gl.BYTE;
        if ( p === ShortType ) return gl.SHORT;
        if ( p === UnsignedShortType ) return gl.UNSIGNED_SHORT;
        if ( p === IntType ) return gl.INT;
        if ( p === UnsignedIntType ) return gl.UNSIGNED_INT;
        if ( p === FloatType ) return gl.FLOAT;
        if ( p === HalfFloatType ) return gl.HALF_FLOAT;

        if ( p === AlphaFormat ) return gl.ALPHA;
        if ( p === RGBFormat ) return gl.RGB;
        if ( p === RGBAFormat ) return gl.RGBA;
        if ( p === DepthFormat ) return gl.DEPTH_COMPONENT;
        if ( p === DepthStencilFormat ) return gl.DEPTH_STENCIL;

        // WebGL2 formats.

        if ( p === RedFormat ) return gl.RED;
        if ( p === RedIntegerFormat ) return gl.RED_INTEGER;
        if ( p === RGFormat ) return gl.RG;
        if ( p === RGIntegerFormat ) return gl.RG_INTEGER;
        if ( p === RGBAIntegerFormat ) return gl.RGBA_INTEGER;

        // S3TC

        if ( p === RGB_S3TC_DXT1_Format || p === RGBA_S3TC_DXT1_Format || p === RGBA_S3TC_DXT3_Format || p === RGBA_S3TC_DXT5_Format ) {

            if ( transfer === SRGBTransfer ) {

                extension = extensions.get( 'WEBGL_compressed_texture_s3tc_srgb' );

                if ( extension !== null ) {

                    if ( p === RGB_S3TC_DXT1_Format ) return extension.COMPRESSED_SRGB_S3TC_DXT1_EXT;
                    if ( p === RGBA_S3TC_DXT1_Format ) return extension.COMPRESSED_SRGB_ALPHA_S3TC_DXT1_EXT;
                    if ( p === RGBA_S3TC_DXT3_Format ) return extension.COMPRESSED_SRGB_ALPHA_S3TC_DXT3_EXT;
                    if ( p === RGBA_S3TC_DXT5_Format ) return extension.COMPRESSED_SRGB_ALPHA_S3TC_DXT5_EXT;

                } else {

                    return null;

                }

            } else {

                extension = extensions.get( 'WEBGL_compressed_texture_s3tc' );

                if ( extension !== null ) {

                    if ( p === RGB_S3TC_DXT1_Format ) return extension.COMPRESSED_RGB_S3TC_DXT1_EXT;
                    if ( p === RGBA_S3TC_DXT1_Format ) return extension.COMPRESSED_RGBA_S3TC_DXT1_EXT;
                    if ( p === RGBA_S3TC_DXT3_Format ) return extension.COMPRESSED_RGBA_S3TC_DXT3_EXT;
                    if ( p === RGBA_S3TC_DXT5_Format ) return extension.COMPRESSED_RGBA_S3TC_DXT5_EXT;

                } else {

                    return null;

                }

            }

        }

        // PVRTC

        if ( p === RGB_PVRTC_4BPPV1_Format || p === RGB_PVRTC_2BPPV1_Format || p === RGBA_PVRTC_4BPPV1_Format || p === RGBA_PVRTC_2BPPV1_Format ) {

            extension = extensions.get( 'WEBGL_compressed_texture_pvrtc' );

            if ( extension !== null ) {

                if ( p === RGB_PVRTC_4BPPV1_Format ) return extension.COMPRESSED_RGB_PVRTC_4BPPV1_IMG;
                if ( p === RGB_PVRTC_2BPPV1_Format ) return extension.COMPRESSED_RGB_PVRTC_2BPPV1_IMG;
                if ( p === RGBA_PVRTC_4BPPV1_Format ) return extension.COMPRESSED_RGBA_PVRTC_4BPPV1_IMG;
                if ( p === RGBA_PVRTC_2BPPV1_Format ) return extension.COMPRESSED_RGBA_PVRTC_2BPPV1_IMG;

            } else {

                return null;

            }

        }

        // ETC

        if ( p === RGB_ETC1_Format || p === RGB_ETC2_Format || p === RGBA_ETC2_EAC_Format ) {

            extension = extensions.get( 'WEBGL_compressed_texture_etc' );

            if ( extension !== null ) {

                if ( p === RGB_ETC1_Format || p === RGB_ETC2_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ETC2 : extension.COMPRESSED_RGB8_ETC2;
                if ( p === RGBA_ETC2_EAC_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ETC2_EAC : extension.COMPRESSED_RGBA8_ETC2_EAC;

            } else {

                return null;

            }

        }

        // ASTC

        if ( p === RGBA_ASTC_4x4_Format || p === RGBA_ASTC_5x4_Format || p === RGBA_ASTC_5x5_Format ||
            p === RGBA_ASTC_6x5_Format || p === RGBA_ASTC_6x6_Format || p === RGBA_ASTC_8x5_Format ||
            p === RGBA_ASTC_8x6_Format || p === RGBA_ASTC_8x8_Format || p === RGBA_ASTC_10x5_Format ||
            p === RGBA_ASTC_10x6_Format || p === RGBA_ASTC_10x8_Format || p === RGBA_ASTC_10x10_Format ||
            p === RGBA_ASTC_12x10_Format || p === RGBA_ASTC_12x12_Format ) {

            extension = extensions.get( 'WEBGL_compressed_texture_astc' );

            if ( extension !== null ) {

                if ( p === RGBA_ASTC_4x4_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_4x4_KHR : extension.COMPRESSED_RGBA_ASTC_4x4_KHR;
                if ( p === RGBA_ASTC_5x4_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_5x4_KHR : extension.COMPRESSED_RGBA_ASTC_5x4_KHR;
                if ( p === RGBA_ASTC_5x5_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_5x5_KHR : extension.COMPRESSED_RGBA_ASTC_5x5_KHR;
                if ( p === RGBA_ASTC_6x5_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_6x5_KHR : extension.COMPRESSED_RGBA_ASTC_6x5_KHR;
                if ( p === RGBA_ASTC_6x6_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_6x6_KHR : extension.COMPRESSED_RGBA_ASTC_6x6_KHR;
                if ( p === RGBA_ASTC_8x5_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_8x5_KHR : extension.COMPRESSED_RGBA_ASTC_8x5_KHR;
                if ( p === RGBA_ASTC_8x6_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_8x6_KHR : extension.COMPRESSED_RGBA_ASTC_8x6_KHR;
                if ( p === RGBA_ASTC_8x8_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_8x8_KHR : extension.COMPRESSED_RGBA_ASTC_8x8_KHR;
                if ( p === RGBA_ASTC_10x5_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_10x5_KHR : extension.COMPRESSED_RGBA_ASTC_10x5_KHR;
                if ( p === RGBA_ASTC_10x6_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_10x6_KHR : extension.COMPRESSED_RGBA_ASTC_10x6_KHR;
                if ( p === RGBA_ASTC_10x8_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_10x8_KHR : extension.COMPRESSED_RGBA_ASTC_10x8_KHR;
                if ( p === RGBA_ASTC_10x10_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_10x10_KHR : extension.COMPRESSED_RGBA_ASTC_10x10_KHR;
                if ( p === RGBA_ASTC_12x10_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_12x10_KHR : extension.COMPRESSED_RGBA_ASTC_12x10_KHR;
                if ( p === RGBA_ASTC_12x12_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB8_ALPHA8_ASTC_12x12_KHR : extension.COMPRESSED_RGBA_ASTC_12x12_KHR;

            } else {

                return null;

            }

        }

        // BPTC

        if ( p === RGBA_BPTC_Format || p === RGB_BPTC_SIGNED_Format || p === RGB_BPTC_UNSIGNED_Format ) {

            extension = extensions.get( 'EXT_texture_compression_bptc' );

            if ( extension !== null ) {

                if ( p === RGBA_BPTC_Format ) return ( transfer === SRGBTransfer ) ? extension.COMPRESSED_SRGB_ALPHA_BPTC_UNORM_EXT : extension.COMPRESSED_RGBA_BPTC_UNORM_EXT;
                if ( p === RGB_BPTC_SIGNED_Format ) return extension.COMPRESSED_RGB_BPTC_SIGNED_FLOAT_EXT;
                if ( p === RGB_BPTC_UNSIGNED_Format ) return extension.COMPRESSED_RGB_BPTC_UNSIGNED_FLOAT_EXT;

            } else {

                return null;

            }

        }

        // RGTC

        if ( p === RED_RGTC1_Format || p === SIGNED_RED_RGTC1_Format || p === RED_GREEN_RGTC2_Format || p === SIGNED_RED_GREEN_RGTC2_Format ) {

            extension = extensions.get( 'EXT_texture_compression_rgtc' );

            if ( extension !== null ) {

                if ( p === RGBA_BPTC_Format ) return extension.COMPRESSED_RED_RGTC1_EXT;
                if ( p === SIGNED_RED_RGTC1_Format ) return extension.COMPRESSED_SIGNED_RED_RGTC1_EXT;
                if ( p === RED_GREEN_RGTC2_Format ) return extension.COMPRESSED_RED_GREEN_RGTC2_EXT;
                if ( p === SIGNED_RED_GREEN_RGTC2_Format ) return extension.COMPRESSED_SIGNED_RED_GREEN_RGTC2_EXT;

            } else {

                return null;

            }

        }

        //

        if ( p === UnsignedInt248Type ) return gl.UNSIGNED_INT_24_8;

        // if "p" can't be resolved, assume the user defines a WebGL constant as a string (fallback/workaround for packed RGB formats)

        return ( gl[ p ] !== undefined ) ? gl[ p ] : null;

    }