Init commit

assembler/util.ts

@@ -0,0 +1,40 @@
+export function toBitString(n: number, bits: number, signed: boolean = false): string {
+	const minimum = -(2 ** (bits - 1));
+	const maximum = signed ? (2 ** (bits - 1)) - 1 : 2 ** bits - 1;
+
+	if (n < minimum || n > maximum) {
+		throw new Error(`Value ${n} out of range for ${bits}-bit ${signed ? 'signed' : 'unsigned'} integer`);
+	}
+
+	if (n < 0) {
+		n = (2 ** bits) + n;
+	}
+
+	let result = '';
+	for (let i = 0; i < bits; i++) {
+		result = (n & 1) + result;
+		n >>= 1;
+	}
+	if (n !== 0) {
+		throw new Error(`Internal error: ${n} not zero after conversion to ${bits}-bit ${signed ? 'signed' : 'unsigned'} integer`);
+	}
+	return result;
+}
+
+export function toNote(n: number, bits: number): string {
+	if (bits <= 19) {
+		return `${n}`;
+	} else {
+		const scaling = 2 ** (bits - 19);
+		return `${(n / scaling).toFixed(5)} x${scaling}`
+	}
+}
+
+export function toNote24(n: number): string {
+	return toNote(n, 24);
+}
+
+export function toNote8(n: number): string {
+	return toNote(n, 8);
+}
+