Spawn in a Grid

Part of the Unity Scripting Basics section of Coddy's Unity journey. Lesson 50 of 67.

A loop inside a loop visits every cell of a grid: the outer loop picks a column, the inner loop walks along it. Put an Instantiate inside and every cell gets an object. This builds a 3 by 3 floor from tiles that are 2 units wide, so the tiles go 2 units apart:

public GameObject tilePrefab;

void Start()
{
    for (int x = 0; x < 3; x++)
    {
        for (int z = 0; z < 3; z++)
        {
            Vector3 spot = new Vector3(x * 2, 0, z * 2);
            Instantiate(tilePrefab, spot, Quaternion.identity, transform);
        }
    }
}

The tiles land at x = 0, 2, 4 and z = 0, 2, 4: nine of them, from (0, 0, 0) to (4, 0, 4). The loops run in Start(), once. In Update() they would add nine more tiles on every frame.

The fourth argument is a parent. Nine loose Tile(Clone) objects would clutter the Hierarchy; passing transform files them under the object this script is on, the Floor, so they can be folded away, moved together or deleted together. The position you pass is still a world position.

Challenge

Medium

Build a brick wall from the Brick prefab, 4 bricks wide and 5 rows high, standing on the ground. A brick is 1 unit wide and 0.5 tall.

The 4 columns are at x = -1.5, -0.5, 0.5 and 1.5.
The bottom row rests on the ground, so its bricks are at y = 0.25. Each row is 0.5 above the one below it.
Every brick is at z = 0, has no rotation and is a child of the Wall, the object this script is on.

Press Play to see the wall, then Check.

Try it yourself

using UnityEngine;

public class WallBuilder : MonoBehaviour
{
    public GameObject brickPrefab;

    void Start()
    {
        // 4 columns by 5 rows of bricks, each a child of this Wall
    }
}