refactor(canvas): 预演台 - 重构工作台与场景交互链路

web/test/previs-path.test.ts

@@ -0,0 +1,37 @@
+import { describe, expect, test } from "bun:test";
+
+import { buildPrevisPathKeyframes, previsPathHeading, simplifyPrevisPath, timePrevisPath } from "@/lib/canvas/previs/previs-path";
+import type { PrevisTransform } from "@/types/previs";
+
+const base: PrevisTransform = { position: [0, 0, 0], rotation: [0, 0, 0], scale: [1, 1, 1] };
+
+describe("previs path authoring", () => {
+    test("removes repeated samples and keeps meaningful corners", () => {
+        expect(simplifyPrevisPath([[0, 0, 0], [0, 0, 0], [0.01, 0, 0.01], [1, 0, 0], [1, 0, 0]], 0.03)).toEqual([[0, 0, 0], [1, 0, 0]]);
+        expect(simplifyPrevisPath([[0, 0, 0], [1, 0, 0], [1, 0, 1]], 0.03)).toEqual([[0, 0, 0], [1, 0, 0], [1, 0, 1]]);
+    });
+
+    test("allocates time by travelled distance", () => {
+        const waypoints = timePrevisPath([[0, 0, 0], [1, 0, 0], [3, 0, 0]], 2, 4);
+        expect(waypoints.map((item) => item.time)).toEqual([2, 2 + 4 / 3, 6]);
+    });
+
+    test("handles degenerate paths without creating invalid data", () => {
+        expect(timePrevisPath([[1, 0, 1], [1, 0, 1]], 0, 5)).toEqual([{ time: 0, position: [1, 0, 1] }]);
+        expect(buildPrevisPathKeyframes({ base, points: [[1, 0, 1]], duration: 5 })).toHaveLength(1);
+    });
+
+    test("derives a stable heading from the path", () => {
+        expect(previsPathHeading([[0, 0, 0], [1, 0, 0]], 0)).toBeCloseTo(Math.PI / 2);
+        expect(previsPathHeading([[0, 0, 0], [0, 0, 1]], 0)).toBeCloseTo(0);
+    });
+
+    test("builds smooth transform keyframes and optionally turns actors along the route", () => {
+        const keyframes = buildPrevisPathKeyframes({ base, points: [[0, 0, 0], [1, 0, 0], [1, 0, 1]], duration: 5, orientToPath: true });
+        expect(keyframes).toHaveLength(3);
+        expect(keyframes[0].easing).toBe("smooth");
+        expect(keyframes[0].transform.position).toEqual([0, 0, 0]);
+        expect(keyframes[1].transform.rotation[1]).toBeCloseTo(Math.PI / 4);
+        expect(keyframes[2].transform.position).toEqual([1, 0, 1]);
+    });
+});