29 lines
639 B
TypeScript
29 lines
639 B
TypeScript
// Finished in earlier steps — reuse, don't rewrite.
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export type Vec = { x: number; y: number };
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export const vec = (x: number, y: number): Vec => ({ x, y });
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export type AABB = { x: number; y: number; w: number; h: number };
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export type Span = { entry: number; exit: number };
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/** Step 05, finished. */
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export function sweepInterval(
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p: number,
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v: number,
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min: number,
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max: number,
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): Span | null {
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if (v === 0) {
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return min <= p && p <= max
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? { entry: -Infinity, exit: Infinity }
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: null;
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}
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let t1 = (min - p) / v;
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let t2 = (max - p) / v;
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if (t1 > t2) {
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[t1, t2] = [t2, t1];
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}
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return { entry: t1, exit: t2 };
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}
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