Method drawCodewords

src/third-party/qrcodegen/index.ts:391–414

(data: Readonly<Array<byte>>)

		// Draws the given sequence of 8-bit codewords (data and error correction) onto the entire
		// data area of this QR Code. Function modules need to be marked off before this is called.
		private drawCodewords(data: Readonly<Array<byte>>): void {
			if (data.length != Math.floor(QrCode.getNumRawDataModules(this.version) / 8))
				throw new RangeError("Invalid argument");
			let i: int = 0;  // Bit index into the data
			// Do the funny zigzag scan
			for (let right = this.size - 1; right >= 1; right -= 2) {  // Index of right column in each column pair
				if (right == 6)
					right = 5;
				for (let vert = 0; vert < this.size; vert++) {  // Vertical counter
					for (let j = 0; j < 2; j++) {
						const x: int = right - j;  // Actual x coordinate
						const upward: boolean = ((right + 1) & 2) == 0;
						const y: int = upward ? this.size - 1 - vert : vert;  // Actual y coordinate
						if (!this.isFunction[y][x] && i < data.length * 8) {
							this.modules[y][x] = getBit(data[i >>> 3], 7 - (i & 7));
							i++;
						}
						// If this QR Code has any remainder bits (0 to 7), they were assigned as
						// 0/false/light by the constructor and are left unchanged by this method
					}
				}
			}
			assert(i == data.length * 8);
		}


		// XORs the codeword modules in this QR Code with the given mask pattern.