l.roughness = 1;
		sphere_material.side = t3d.DRAW_SIDE.DOUBLE;
		const sphere = new t3d.Mesh(sphere_geometry, sphere_material);
		sphere.position.set(-2, 10, -30);
		sphere.shadowType = t3d.SHADOW_TYPE.PCF5_SOFT;
		sphere.castShadow = true;
		sphere.receiveShadow = true;
		scene.add(sphere);

		const box_geometry = new t3d.BoxGeometry(20, 40, 20);
		const box_material = new t3d.PBRMaterial();
		box_material.diffuse.setHex(0xBBBBBB);
		box_material.metalness = 0;
		box_material.roughness = 1;
		box_material