3D coordinate system in Unity - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

What is the output of this Vector3 addition?

Consider the following Unity C# code snippet. What will be printed to the console?

Unity

using UnityEngine;

public class TestVector : MonoBehaviour {
    void Start() {
        Vector3 a = new Vector3(1, 2, 3);
        Vector3 b = new Vector3(4, 5, 6);
        Vector3 c = a + b;
        Debug.Log(c);
    }
}

A (3.0, 7.0, 9.0)

B (5.0, 7.0, 9.0)

C (4.0, 5.0, 6.0)

D (1.0, 2.0, 3.0)

💡 Hint

Remember that Vector3 addition adds each coordinate separately.

Adding two Vector3 objects sums their x, y, and z components respectively. So (1+4, 2+5, 3+6) = (5,7,9).

🧠 Conceptual

intermediate

Which axis points upwards in Unity's 3D coordinate system?

In Unity's default 3D coordinate system, which axis represents the vertical direction (up)?

A X axis

B Negative Y axis

C Y axis

D Z axis

💡 Hint

Think about which axis controls height in the scene view.

In Unity, the Y axis points upwards, representing vertical height.

🔧 Debug

advanced

Why does this code produce an unexpected movement?

This code is intended to move an object 5 units forward along the Z axis, but it moves only 1 unit forward instead. Why?

Unity

using UnityEngine;

public class MoveObject : MonoBehaviour {
    void Start() {
        Vector3 move = new Vector3(0, 0, 5);
        transform.position += move.normalized;
    }
}

A Because move.normalized changes the vector length to 1, so it moves only 1 unit forward.

B Because transform.position cannot be changed directly.

C Because the vector should be multiplied by Time.deltaTime.

D Because the vector should be added without normalization.

💡 Hint

Check what normalized does to a vector's length.

Normalizing a vector changes its length to 1 but keeps direction. So adding move.normalized moves the object 1 unit, not 5, along the same direction.

📝 Syntax

advanced

Which code correctly creates a Vector3 pointing left?

Select the code snippet that correctly creates a Vector3 pointing left in Unity's 3D space.

A Vector3 left = new Vector3(0, -1, 0);

B Vector3 left = new Vector3(0, 0, -1);

C Vector3 left = new Vector3(1, 0, 0);

D Vector3 left = new Vector3(-1, 0, 0);

💡 Hint

Left means negative direction along the X axis.

In Unity, the X axis points right, so left is negative X: (-1, 0, 0).

🚀 Application

expert

How many unique Vector3 points are generated by this nested loop?

Consider this code that generates Vector3 points in a 3D grid: int count = 0; for (int x = 0; x < 3; x++) { for (int y = 0; y < 2; y++) { for (int z = 0; z < 4; z++) { Vector3 point = new Vector3(x, y, z); count++; } } } What is the value of count after this code runs?

A 24

B 9

C 12

D 18

💡 Hint

Multiply the number of iterations in each loop.

The loops run 3 * 2 * 4 = 24 times, so count is 24.