playcanvas/build/playcanvas/src/core/read-stream.js

Open-source WebGL/WebGPU 3D engine for the web

class ReadStream {
	arraybuffer;
	dataView;
	offset = 0;
	constructor(arraybuffer) {
		this.arraybuffer = arraybuffer;
		this.dataView = new DataView(arraybuffer);
	}
	get remainingBytes() {
		return this.dataView.byteLength - this.offset;
	}
	reset(offset = 0) {
		this.offset = offset;
	}
	skip(bytes) {
		this.offset += bytes;
	}
	align(bytes) {
		this.offset = this.offset + bytes - 1 & ~(bytes - 1);
	}
	_inc(amount) {
		this.offset += amount;
		return this.offset - amount;
	}
	readChar() {
		return String.fromCharCode(this.dataView.getUint8(this.offset++));
	}
	readChars(numChars) {
		let result = "";
		for (let i = 0; i < numChars; ++i) {
			result += this.readChar();
		}
		return result;
	}
	readU8() {
		return this.dataView.getUint8(this.offset++);
	}
	readU16() {
		return this.dataView.getUint16(this._inc(2), true);
	}
	readU32() {
		return this.dataView.getUint32(this._inc(4), true);
	}
	readU64() {
		return this.readU32() + 2 ** 32 * this.readU32();
	}
	readU32be() {
		return this.dataView.getUint32(this._inc(4), false);
	}
	readArray(result) {
		for (let i = 0; i < result.length; ++i) {
			result[i] = this.readU8();
		}
	}
	readLine() {
		const view = this.dataView;
		let result = "";
		while (true) {
			if (this.offset >= view.byteLength) {
				break;
			}
			const c = String.fromCharCode(this.readU8());
			if (c === "\n") {
				break;
			}
			result += c;
		}
		return result;
	}
}
export {
	ReadStream
};