time for a snapshot

workshop/steps/07-swept-aabb/swept.ts

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+import { type AABB, type Hit, rayVsAABB, type Vec } from "./given.ts";
+
+/**
+ * A moving box `a` (velocity `v` over this frame) vs a static box `b`.
+ *
+ * Inflate `b` by `a`'s size (Minkowski sum), collapse `a` to its corner point,
+ * then reuse rayVsAABB. Return its Hit, or null for no collision this frame.
+ */
+export function sweptAABB(a: AABB, v: Vec, b: AABB): Hit | null {
+	const inflated: AABB = {
+		x: b.x - a.w,
+		y: b.y - a.h,
+		w: b.w + a.w,
+		h: b.h + a.h,
+	};
+
+	const point: Vec = { x: a.x, y: a.y };
+
+	return rayVsAABB(point, v, inflated);
+}