vtf-js/dist/core/buffer.js

A javascript IO library for the Valve Texture Format.

const TE = new TextEncoder();
const TD = new TextDecoder();
/**
 * Wraps DataView with utility functions and pointer offsets.
 * This class is also available separately in the `stupid-buffer` npm package.
 */
export class DataBuffer extends Uint8Array {
    pointer = 0;
    view;
    little = true;
    constructor(buffer, byteOffset, length) {
        // @ts-expect-error When initializing a Uint8Array from another array, byteOffset and length
        // are disregarded for some reason. This is just a quick hack to make it work as expected.
        if (typeof buffer === 'object' && 'buffer' in buffer)
            buffer = buffer.buffer;
        // @ts-expect-error JUST MAKE IT WORK.
        super(buffer, byteOffset, length);
        this.view = new DataView(this.buffer, this.byteOffset, this.byteLength);
    }
    /** Sets the default endianness of the DataBuffer. */
    set_endian(little) {
        this.little = little;
    }
    /** Creates a new DataBuffer within the specified bounds. */
    ref(start = 0, length = this.length - start) {
        const buf = new DataBuffer(this.buffer, start + this.byteOffset, length);
        buf.set_endian(this.little);
        return buf;
    }
    /** Moves the pointer to the specified position. */
    seek(position) {
        this.pointer = position;
    }
    /** Increments the pointer by the specified number of bytes. */
    pad(length) {
        this.pointer += length;
    }
    /** Aligns the pointer to the nearest multiple specified, and pads a number of bytes if specified. */
    align(multiple, offset) {
        this.pointer = (offset ?? 0) + this.pointer + (multiple - this.pointer % multiple) % multiple;
    }
    read_u8(length) {
        const start = this.pointer;
        if (length === undefined) {
            this.pointer++;
            return this.view.getUint8(start);
        }
        this.pointer += length;
        return new Uint8Array(this.slice(start, this.pointer));
    }
    write_u8(value) {
        const start = this.pointer;
        if (typeof value === 'number') {
            this.pointer++;
            return this.view.setUint8(start, value);
        }
        this.pointer += value.length;
        this.set(value, start);
        return;
    }
    read_u16(length, little = this.little) {
        const start = this.pointer;
        if (length === undefined) {
            this.pointer += 2;
            return this.view.getUint16(start, little);
        }
        this.pointer += length * 2;
        const arr = new Uint16Array(length);
        for (let i = 0; i < length; i++)
            arr[i] = this.view.getUint16(start + i * 2, little);
        return arr;
    }
    write_u16(value, little = this.little) {
        const start = this.pointer;
        if (typeof value === 'number') {
            this.pointer += 2;
            return this.view.setUint16(start, value, little);
        }
        this.pointer += value.length * 2;
        for (let i = 0; i < value.length; i++)
            this.view.setUint16(start + i * 2, value[i], little);
        return;
    }
    read_u32(length, little = this.little) {
        const start = this.pointer;
        if (length === undefined) {
            this.pointer += 4;
            return this.view.getUint32(start, little);
        }
        this.pointer += length * 4;
        const arr = new Uint32Array(length);
        for (let i = 0; i < length; i++)
            arr[i] = this.view.getUint32(start + i * 4, little);
        return arr;
    }
    write_u32(value, little = this.little) {
        const start = this.pointer;
        if (typeof value === 'number') {
            this.pointer += 4;
            return this.view.setUint32(start, value, little);
        }
        this.pointer += value.length * 4;
        for (let i = 0; i < value.length; i++)
            this.view.setUint32(start + i * 4, value[i], little);
        return;
    }
    read_i8(length) {
        const start = this.pointer;
        if (length === undefined) {
            this.pointer++;
            return this.view.getInt8(start);
        }
        this.pointer += length;
        return new Int8Array(this.slice(start, this.pointer));
    }
    write_i8(value) {
        const start = this.pointer;
        if (typeof value === 'number') {
            this.pointer++;
            return this.view.setInt8(start, value);
        }
        this.pointer += value.length;
        this.set(value, start);
        return;
    }
    read_i16(length, little = this.little) {
        const start = this.pointer;
        if (length === undefined) {
            this.pointer += 2;
            return this.view.getInt16(start, little);
        }
        this.pointer += length * 2;
        const arr = new Int16Array(length);
        for (let i = 0; i < length; i++)
            arr[i] = this.view.getInt16(start + i * 2, little);
        return arr;
    }
    write_i16(value, little = this.little) {
        const start = this.pointer;
        if (typeof value === 'number') {
            this.pointer += 2;
            return this.view.setInt16(start, value, little);
        }
        this.pointer += value.length * 2;
        for (let i = 0; i < value.length; i++)
            this.view.setInt16(start + i * 2, value[i], little);
        return;
    }
    read_i32(length, little = this.little) {
        const start = this.pointer;
        if (length === undefined) {
            this.pointer += 4;
            return this.view.getInt32(start, little);
        }
        this.pointer += length * 4;
        const arr = new Int32Array(length);
        for (let i = 0; i < length; i++)
            arr[i] = this.view.getInt32(start + i * 4, little);
        return arr;
    }
    write_i32(value, little = this.little) {
        const start = this.pointer;
        if (typeof value === 'number') {
            this.pointer += 4;
            return this.view.setInt32(start, value, little);
        }
        this.pointer += value.length * 4;
        for (let i = 0; i < value.length; i++)
            this.view.setInt32(start + i * 4, value[i], little);
        return;
    }
    read_f32(length, little = this.little) {
        const start = this.pointer;
        if (length === undefined) {
            this.pointer += 4;
            return this.view.getFloat32(start, little);
        }
        this.pointer += length * 4;
        const arr = new Float32Array(length);
        for (let i = 0; i < length; i++)
            arr[i] = this.view.getFloat32(start + i * 4, little);
        return arr;
    }
    write_f32(value, little = this.little) {
        const start = this.pointer;
        if (typeof value === 'number') {
            this.pointer += 4;
            return this.view.setFloat32(start, value, little);
        }
        this.pointer += value.length * 4;
        for (let i = 0; i < value.length; i++)
            this.view.setFloat32(start + i * 4, value[i], little);
        return;
    }
    read_f64(length, little = this.little) {
        const start = this.pointer;
        if (length === undefined) {
            this.pointer += 8;
            return this.view.getFloat64(start, little);
        }
        this.pointer += length * 8;
        const arr = new Float64Array(length);
        for (let i = 0; i < length; i++)
            arr[i] = this.view.getFloat64(start + i * 8, little);
        return arr;
    }
    write_f64(value, little = this.little) {
        const start = this.pointer;
        if (typeof value === 'number') {
            this.pointer += 8;
            return this.view.setFloat64(start, value, little);
        }
        this.pointer += value.length * 8;
        for (let i = 0; i < value.length; i++)
            this.view.setFloat64(start + i * 8, value[i], little);
        return;
    }
    read_str(length) {
        const start = this.pointer;
        let end = start + length;
        if (length === undefined) {
            for (end = start; end < this.length; end++) {
                if (this.view.getUint8(end) == 0)
                    break;
            }
            this.pointer++;
        }
        this.pointer += end - start;
        return TD.decode(this.slice(start, end));
    }
    write_str(str, length) {
        const start = this.pointer;
        this.pointer += str.length;
        this.set(TE.encode(str), start);
        if (length === undefined) {
            this.view.setUint8(this.pointer, 0);
            this.pointer++;
        }
        else if (str.length !== length) {
            throw RangeError('String of length ' + str.length + ' does not match write length of ' + length + '!');
        }
    }
}