9 lines
378 B
TypeScript
9 lines
378 B
TypeScript
export function rotate(x: number, y: number, cx: number, cy: number, angleDegrees: number): [number, number] {
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const angleRad = (Math.PI / 180) * angleDegrees * -1;
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const cos = Math.cos(angleRad);
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const sin = Math.sin(angleRad);
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const nx = (cos * (x - cx)) + (sin * (y - cy)) + cx;
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const ny = (cos * (y - cy)) - (sin * (x - cx)) + cy;
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return [nx, ny];
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}
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