playcanvas
Version:
Open-source WebGL/WebGPU 3D engine for the web
144 lines (143 loc) • 4.07 kB
JavaScript
import {
ADDRESS_CLAMP_TO_EDGE,
ADDRESS_REPEAT,
PIXELFORMAT_DXT1,
PIXELFORMAT_DXT3,
PIXELFORMAT_DXT5,
PIXELFORMAT_ETC1,
PIXELFORMAT_ETC2_RGB,
PIXELFORMAT_ETC2_RGBA,
PIXELFORMAT_PVRTC_4BPP_RGB_1,
PIXELFORMAT_PVRTC_2BPP_RGB_1,
PIXELFORMAT_PVRTC_4BPP_RGBA_1,
PIXELFORMAT_PVRTC_2BPP_RGBA_1,
PIXELFORMAT_RGB8,
PIXELFORMAT_RGBA8,
PIXELFORMAT_SRGB8,
PIXELFORMAT_SRGBA8,
PIXELFORMAT_111110F,
PIXELFORMAT_RGB16F,
PIXELFORMAT_RGBA16F,
TEXHINT_ASSET,
pixelFormatLinearToGamma
} from "../../../platform/graphics/constants.js";
import { Texture } from "../../../platform/graphics/texture.js";
import { Asset } from "../../asset/asset.js";
import { TextureParser } from "./texture.js";
const IDENTIFIER = [1481919403, 3140563232, 169478669];
const KNOWN_FORMATS = {
// compressed formats
33776: PIXELFORMAT_DXT1,
33778: PIXELFORMAT_DXT3,
33779: PIXELFORMAT_DXT5,
36196: PIXELFORMAT_ETC1,
37492: PIXELFORMAT_ETC2_RGB,
37496: PIXELFORMAT_ETC2_RGBA,
35840: PIXELFORMAT_PVRTC_4BPP_RGB_1,
35841: PIXELFORMAT_PVRTC_2BPP_RGB_1,
35842: PIXELFORMAT_PVRTC_4BPP_RGBA_1,
35843: PIXELFORMAT_PVRTC_2BPP_RGBA_1,
// uncompressed formats
32849: PIXELFORMAT_RGB8,
// GL_RGB8
32856: PIXELFORMAT_RGBA8,
// GL_RGBA8
35905: PIXELFORMAT_SRGB8,
// GL_SRGB8
35907: PIXELFORMAT_SRGBA8,
// GL_SRGB8_ALPHA8
35898: PIXELFORMAT_111110F,
// GL_R11F_G11F_B10F
34843: PIXELFORMAT_RGB16F,
// GL_RGB16F
34842: PIXELFORMAT_RGBA16F
// GL_RGBA16F
};
function createContainer(pixelFormat, buffer, byteOffset, byteSize) {
return pixelFormat === PIXELFORMAT_111110F ? new Uint32Array(buffer, byteOffset, byteSize / 4) : new Uint8Array(buffer, byteOffset, byteSize);
}
class KtxParser extends TextureParser {
constructor(registry) {
super();
this.maxRetries = 0;
}
load(url, callback, asset) {
Asset.fetchArrayBuffer(url.load, callback, asset, this.maxRetries);
}
open(url, data, device, textureOptions = {}) {
const textureData = this.parse(data);
if (!textureData) {
return null;
}
const format = textureOptions.srgb ? pixelFormatLinearToGamma(textureData.format) : textureData.format;
const texture = new Texture(device, {
name: url,
addressU: textureData.cubemap ? ADDRESS_CLAMP_TO_EDGE : ADDRESS_REPEAT,
addressV: textureData.cubemap ? ADDRESS_CLAMP_TO_EDGE : ADDRESS_REPEAT,
width: textureData.width,
height: textureData.height,
format,
cubemap: textureData.cubemap,
levels: textureData.levels,
...textureOptions
});
texture.upload();
return texture;
}
parse(data) {
const dataU32 = new Uint32Array(data);
if (IDENTIFIER[0] !== dataU32[0] || IDENTIFIER[1] !== dataU32[1] || IDENTIFIER[2] !== dataU32[2]) {
return null;
}
const header = {
endianness: dataU32[3],
// todo: Use this information
glType: dataU32[4],
glTypeSize: dataU32[5],
glFormat: dataU32[6],
glInternalFormat: dataU32[7],
glBaseInternalFormat: dataU32[8],
pixelWidth: dataU32[9],
pixelHeight: dataU32[10],
pixelDepth: dataU32[11],
numberOfArrayElements: dataU32[12],
numberOfFaces: dataU32[13],
numberOfMipmapLevels: dataU32[14],
bytesOfKeyValueData: dataU32[15]
};
if (header.pixelDepth > 1) {
return null;
}
if (header.numberOfArrayElements !== 0) {
return null;
}
const format = KNOWN_FORMATS[header.glInternalFormat];
if (format === void 0) {
return null;
}
let offset = 16 + header.bytesOfKeyValueData / 4;
const isCubemap = header.numberOfFaces > 1;
const levels = [];
for (let mipmapLevel = 0; mipmapLevel < (header.numberOfMipmapLevels || 1); mipmapLevel++) {
const imageSizeInBytes = dataU32[offset++];
if (isCubemap) {
levels.push([]);
}
const target = isCubemap ? levels[mipmapLevel] : levels;
for (let face = 0; face < (isCubemap ? 6 : 1); ++face) {
target.push(createContainer(format, data, offset * 4, imageSizeInBytes));
offset += imageSizeInBytes + 3 >> 2;
}
}
return {
format,
width: header.pixelWidth,
height: header.pixelHeight,
levels,
cubemap: isCubemap
};
}
}
export {
KtxParser
};