Function project

packages/melonjs/tests/sprite3d.spec.js:586–598

()

		cam.lookAt(0, 0, 0);
		const s = makeAnimated({ billboard: "cylindrical" });
		const project = () => {
			s._billboardCam = cam;
			s._projectVerticesWorld(0, 0, 0);
			const c0 = cam.worldToScreen(
				new Vector3d(s.vertices[0], s.vertices[1], s.vertices[2]),
				new Vector2d(),
			);
			const c1 = cam.worldToScreen(
				new Vector3d(s.vertices[3], s.vertices[4], s.vertices[5]),
				new Vector2d(),
			);
			return { c0, c1 };
		};
		const before = project();
		expect(before.c0.x).toBeLessThan(before.c1.x); // BL left of BR
		s.flipX();