27 lines
654 B
TypeScript
27 lines
654 B
TypeScript
export const getZoomOrigin = (
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canvas: HTMLCanvasElement | null,
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scale: number,
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) => {
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if (canvas === null) {
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return { x: 0, y: 0 };
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}
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const context = canvas.getContext("2d");
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if (context === null) {
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return { x: 0, y: 0 };
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}
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const normalizedCanvasWidth = canvas.width / scale;
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const normalizedCanvasHeight = canvas.height / scale;
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return {
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x: normalizedCanvasWidth / 2,
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y: normalizedCanvasHeight / 2,
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};
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};
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export const getNormalizedZoom = (zoom: number): number => {
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const normalizedZoom = parseFloat(zoom.toFixed(2));
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const clampedZoom = Math.max(0.1, Math.min(normalizedZoom, 2));
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return clampedZoom;
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};
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