@kibeo/loaders.gl-textures/dist/esm/lib/parsers/parse-pvr.js

Framework-independent loaders for compressed and super compressed (basis) textures

import { GL } from '../gl-constants';
import { extractMipmapImages } from '../utils/extract-mipmap-images';
const PVR_CONSTANTS = {
  MAGIC_NUMBER: 0x03525650,
  MAGIC_NUMBER_EXTRA: 0x50565203,
  HEADER_LENGTH: 13,
  HEADER_SIZE: 52,
  MAGIC_NUMBER_INDEX: 0,
  PIXEL_FORMAT_INDEX: 2,
  COLOUR_SPACE_INDEX: 4,
  HEIGHT_INDEX: 6,
  WIDTH_INDEX: 7,
  MIPMAPCOUNT_INDEX: 11,
  METADATA_SIZE_INDEX: 12
};
const PVR_PIXEL_FORMATS = {
  0: [GL.COMPRESSED_RGB_PVRTC_2BPPV1_IMG],
  1: [GL.COMPRESSED_RGBA_PVRTC_2BPPV1_IMG],
  2: [GL.COMPRESSED_RGB_PVRTC_4BPPV1_IMG],
  3: [GL.COMPRESSED_RGBA_PVRTC_4BPPV1_IMG],
  6: [GL.COMPRESSED_RGB_ETC1_WEBGL],
  7: [GL.COMPRESSED_RGB_S3TC_DXT1_EXT],
  9: [GL.COMPRESSED_RGBA_S3TC_DXT3_EXT],
  11: [GL.COMPRESSED_RGBA_S3TC_DXT5_EXT],
  22: [GL.COMPRESSED_RGB8_ETC2],
  23: [GL.COMPRESSED_RGBA8_ETC2_EAC],
  24: [GL.COMPRESSED_RGB8_PUNCHTHROUGH_ALPHA1_ETC2],
  25: [GL.COMPRESSED_R11_EAC],
  26: [GL.COMPRESSED_RG11_EAC],
  27: [GL.COMPRESSED_RGBA_ASTC_4X4_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_4X4_KHR],
  28: [GL.COMPRESSED_RGBA_ASTC_5X4_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_5X4_KHR],
  29: [GL.COMPRESSED_RGBA_ASTC_5X5_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_5X5_KHR],
  30: [GL.COMPRESSED_RGBA_ASTC_6X5_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_6X5_KHR],
  31: [GL.COMPRESSED_RGBA_ASTC_6X6_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_6X6_KHR],
  32: [GL.COMPRESSED_RGBA_ASTC_8X5_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_8X5_KHR],
  33: [GL.COMPRESSED_RGBA_ASTC_8X6_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_8X6_KHR],
  34: [GL.COMPRESSED_RGBA_ASTC_8X8_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_8X8_KHR],
  35: [GL.COMPRESSED_RGBA_ASTC_10X5_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_10X5_KHR],
  36: [GL.COMPRESSED_RGBA_ASTC_10X6_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_10X6_KHR],
  37: [GL.COMPRESSED_RGBA_ASTC_10X8_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_10X8_KHR],
  38: [GL.COMPRESSED_RGBA_ASTC_10X10_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_10X10_KHR],
  39: [GL.COMPRESSED_RGBA_ASTC_12X10_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_12X10_KHR],
  40: [GL.COMPRESSED_RGBA_ASTC_12X12_KHR, GL.COMPRESSED_SRGB8_ALPHA8_ASTC_12X12_KHR]
};
const PVR_SIZE_FUNCTIONS = {
  0: pvrtc2bppSize,
  1: pvrtc2bppSize,
  2: pvrtc4bppSize,
  3: pvrtc4bppSize,
  6: dxtEtcSmallSize,
  7: dxtEtcSmallSize,
  9: dxtEtcAstcBigSize,
  11: dxtEtcAstcBigSize,
  22: dxtEtcSmallSize,
  23: dxtEtcAstcBigSize,
  24: dxtEtcSmallSize,
  25: dxtEtcSmallSize,
  26: dxtEtcAstcBigSize,
  27: dxtEtcAstcBigSize,
  28: atc5x4Size,
  29: atc5x5Size,
  30: atc6x5Size,
  31: atc6x6Size,
  32: atc8x5Size,
  33: atc8x6Size,
  34: atc8x8Size,
  35: atc10x5Size,
  36: atc10x6Size,
  37: atc10x8Size,
  38: atc10x10Size,
  39: atc12x10Size,
  40: atc12x12Size
};
export function isPVR(data) {
  const header = new Uint32Array(data, 0, PVR_CONSTANTS.HEADER_LENGTH);
  const version = header[PVR_CONSTANTS.MAGIC_NUMBER_INDEX];
  return version === PVR_CONSTANTS.MAGIC_NUMBER || version === PVR_CONSTANTS.MAGIC_NUMBER_EXTRA;
}
export function parsePVR(data) {
  const header = new Uint32Array(data, 0, PVR_CONSTANTS.HEADER_LENGTH);
  const pvrFormat = header[PVR_CONSTANTS.PIXEL_FORMAT_INDEX];
  const colourSpace = header[PVR_CONSTANTS.COLOUR_SPACE_INDEX];
  const pixelFormats = PVR_PIXEL_FORMATS[pvrFormat] || [];
  const internalFormat = pixelFormats.length > 1 && colourSpace ? pixelFormats[1] : pixelFormats[0];
  const sizeFunction = PVR_SIZE_FUNCTIONS[pvrFormat];
  const mipMapLevels = header[PVR_CONSTANTS.MIPMAPCOUNT_INDEX];
  const width = header[PVR_CONSTANTS.WIDTH_INDEX];
  const height = header[PVR_CONSTANTS.HEIGHT_INDEX];
  const dataOffset = PVR_CONSTANTS.HEADER_SIZE + header[PVR_CONSTANTS.METADATA_SIZE_INDEX];
  const image = new Uint8Array(data, dataOffset);
  return extractMipmapImages(image, {
    mipMapLevels,
    width,
    height,
    sizeFunction,
    internalFormat
  });
}

function pvrtc2bppSize(width, height) {
  width = Math.max(width, 16);
  height = Math.max(height, 8);
  return width * height / 4;
}

function pvrtc4bppSize(width, height) {
  width = Math.max(width, 8);
  height = Math.max(height, 8);
  return width * height / 2;
}

function dxtEtcSmallSize(width, height) {
  return Math.floor((width + 3) / 4) * Math.floor((height + 3) / 4) * 8;
}

function dxtEtcAstcBigSize(width, height) {
  return Math.floor((width + 3) / 4) * Math.floor((height + 3) / 4) * 16;
}

function atc5x4Size(width, height) {
  return Math.floor((width + 4) / 5) * Math.floor((height + 3) / 4) * 16;
}

function atc5x5Size(width, height) {
  return Math.floor((width + 4) / 5) * Math.floor((height + 4) / 5) * 16;
}

function atc6x5Size(width, height) {
  return Math.floor((width + 5) / 6) * Math.floor((height + 4) / 5) * 16;
}

function atc6x6Size(width, height) {
  return Math.floor((width + 5) / 6) * Math.floor((height + 5) / 6) * 16;
}

function atc8x5Size(width, height) {
  return Math.floor((width + 7) / 8) * Math.floor((height + 4) / 5) * 16;
}

function atc8x6Size(width, height) {
  return Math.floor((width + 7) / 8) * Math.floor((height + 5) / 6) * 16;
}

function atc8x8Size(width, height) {
  return Math.floor((width + 7) / 8) * Math.floor((height + 7) / 8) * 16;
}

function atc10x5Size(width, height) {
  return Math.floor((width + 9) / 10) * Math.floor((height + 4) / 5) * 16;
}

function atc10x6Size(width, height) {
  return Math.floor((width + 9) / 10) * Math.floor((height + 5) / 6) * 16;
}

function atc10x8Size(width, height) {
  return Math.floor((width + 9) / 10) * Math.floor((height + 7) / 8) * 16;
}

function atc10x10Size(width, height) {
  return Math.floor((width + 9) / 10) * Math.floor((height + 9) / 10) * 16;
}

function atc12x10Size(width, height) {
  return Math.floor((width + 11) / 12) * Math.floor((height + 9) / 10) * 16;
}

function atc12x12Size(width, height) {
  return Math.floor((width + 11) / 12) * Math.floor((height + 11) / 12) * 16;
}
//# sourceMappingURL=parse-pvr.js.map