vtf-js/dist/addons/squish.js

A javascript IO library for the Valve Texture Format.

import { CompressImage, DecompressImage, DxtFlags } from 'libsquish-js';
import { registerCodec, VImageData, VEncodedImageData, getCodec } from '../core/image.js';
import { VFormats } from '../core/enums.js';
import { ceil4 } from '../core/utils.js';
function padImage(img) {
    const width = ceil4(img.width);
    const height = ceil4(img.height);
    const src_u32 = new Uint32Array(img.data.buffer);
    const out_u32 = new Uint32Array(width * height);
    for (let y = 0; y < height; y++) {
        if (y >= img.height)
            continue;
        for (let x = 0; x < width; x++) {
            if (x >= img.width)
                continue;
            out_u32[y * width + x] = src_u32[y * img.width + x];
        }
    }
    return new VImageData(new Uint8Array(out_u32.buffer), img.width, img.height);
}
function cropImage(img) {
    const width = ceil4(img.width);
    const src_u32 = new Uint32Array(img.data.buffer);
    const out_u32 = new Uint32Array(img.width * img.height);
    for (let y = 0; y < img.height; y++) {
        for (let x = 0; x < img.width; x++) {
            out_u32[y * img.width + x] = src_u32[y * width + x];
        }
    }
    return new VImageData(new Uint8Array(out_u32.buffer), img.width, img.height);
}
registerCodec(VFormats.DXT1, {
    length(width, height) {
        return ceil4(width) * ceil4(height) * 0.5;
    },
    encode(image) {
        const padded = padImage(image.convert(Uint8Array));
        const input = { data: padded.data, width: ceil4(padded.width), height: ceil4(padded.height) };
        const encoded = CompressImage(input, DxtFlags.kDxt1);
        return new VEncodedImageData(encoded, image.width, image.height, VFormats.DXT1);
    },
    decode(image) {
        const input = { data: image.data, width: ceil4(image.width), height: ceil4(image.height) };
        const decoded = DecompressImage(input, DxtFlags.kDxt1);
        const cropped = cropImage(new VImageData(decoded, image.width, image.height));
        return cropped;
    },
});
registerCodec(VFormats.DXT1_ONEBITALPHA, getCodec(VFormats.DXT1));
registerCodec(VFormats.DXT3, {
    length(width, height) {
        return ceil4(width) * ceil4(height);
    },
    encode(image) {
        const padded = padImage(image.convert(Uint8Array));
        const input = { data: padded.data, width: ceil4(padded.width), height: ceil4(padded.height) };
        const encoded = CompressImage(input, DxtFlags.kDxt3);
        return new VEncodedImageData(encoded, image.width, image.height, VFormats.DXT3);
    },
    decode(image) {
        const input = { data: image.data, width: ceil4(image.width), height: ceil4(image.height) };
        const decoded = DecompressImage(input, DxtFlags.kDxt3);
        const cropped = cropImage(new VImageData(decoded, image.width, image.height));
        return cropped;
    },
});
registerCodec(VFormats.DXT5, {
    length(width, height) {
        return ceil4(width) * ceil4(height);
    },
    encode(image) {
        const padded = padImage(image.convert(Uint8Array));
        const input = { data: padded.data, width: ceil4(padded.width), height: ceil4(padded.height) };
        const encoded = CompressImage(input, DxtFlags.kDxt5);
        return new VEncodedImageData(encoded, image.width, image.height, VFormats.DXT5);
    },
    decode(image) {
        const input = { data: image.data, width: ceil4(image.width), height: ceil4(image.height) };
        const decoded = DecompressImage(input, DxtFlags.kDxt5);
        const cropped = cropImage(new VImageData(decoded, image.width, image.height));
        return cropped;
    },
});