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📗 [1 points] Given a box = new THREE.Mesh(...); is at the origin, which of the following are equivalent to box.translateX(1);?

box.position.set(1, 0, 0);
box.position.x = 1;
box.translateOnAxis(new THREE.Vector3(1, 0, 0), 1);
box.position[0] = 1
box.position.set(0, 1, 0);
None of the above.

📗 [1 points] Given a box = new THREE.Mesh(...); with no rotation and scaling applied to it, which of the following are equivalent to box.rotateX(Math.PI/2); box.scale.set(2, 0, 0);?

box.scale.set(2, 0, 0); box.rotateX(Math.PI/2);
box.scale.set(0, 2, 0); box.rotateX(Math.PI/2);
box.scale.set(0, 0, 2); box.rotateX(Math.PI/2);
box.scale.set(2, 0, 0); box.rotateY(Math.PI/2);
box.scale.set(2, 0, 0); box.rotateZ(Math.PI/2);
None of the above.

📗 [1 points] Given a box = new THREE.Mesh(...); and a sphere = new THREE.Mesh(...); sphere.position.set(1, 0, 0);, how to rotate the sphere around the box as a function of time?

box.add(sphere); box.rotateX(time);
box.add(sphere); sphere.rotateX(time);
sphere.add(box); box.rotateX(time);
sphere.add(box); sphere.rotateX(time);
sphere.rotateOnAxis(box.position, time);
None of the above.

📗 [1 points] Given a box = new THREE.Mesh(...); and a sphere = new THREE.Mesh(); sphere.position.set(Math.sin(time), Math.cos(time), 0); animated as a function of time, how to make the box always face (or look at) the sphere as the sphere is moving? Assume scene.parent is the scene.

box.lookAt(sphere.position);
box.lookAt(sphere.getWorldPosition(new THREE.Vector3()));
box.lookAt(sphere.position.x, sphere.position.y, sphere.position.z);;
box.lookAt(sphere);
box.lookAt(sphere.x, sphere.y, sphere.z);
None of the above.

📗 [1 points] Which of the following can be the second row in a 3D rotation matrix whose first row is [1, 0, 0]?

[0, 1, 0]
[0, 0, 1]
[0, 1, 1]
[1, 0, 0]
[0, 0, 0]
None of the above.

📗 [1 points] What is 1 + 2 i times 3 + 4 i? Note: i is Math.sqrt(-1).

-5 + 10 i
3 + 8 i
4 + 6 i
-5
11 + 10 i
None of the above.

📗 [1 points] What is the unit quaterion representation of a rotation around y-axis [0, 1, 0] of 180 degrees or Math.PI?

new THREE.Quaternion(0, 0, 1, 0);
new THREE.Quaternion(1, 0, 0, 0);
new THREE.Quaternion(1, 0, 1, 0);
new THREE.Quaternion(0, 0, 0, 0);
new THREE.Quaternion(0, 1, 0, 0);
None of the above.

📗 [1 points] Given a box = new THREE.Mesh(...) with the default box.up in the Y-axis direction and initial rotation box.lookAt(0, 0, 1);, which of the following are equivalent to box.lookAt(1, 0, 0);? Note: rotation angles are counterclockwise.

box.rotateY(Math.PI/2);
box.rotateY(-Math.PI/2);
box.rotateX(Math.PI/2);
box.rotateX(-Math.PI/2);
box.rotateZ(Math.PI/2);
None of the above.

# QS7: Week 7 Survey Questions

# Grade

# Submission