Creating lasers in Unity

2 min readMar 24, 2021

For today’s article, I’ll be going over how I let the player shoot lasers using the space bar.

Goals

Have the laser spawn above the player
Have the laser spawn above the player when pressing space bar
Apply upward velocity to laser when spawned

Spawning Lasers

In Unity, there is a built-in function called Instantiate that allows the Player script to spawn projectiles or lasers. The arguments or parameters Instantiate takes in are the prefab game object, starting location (Vector3), and starting rotation (Quaternion).

The SerializeField attribute enables Unity to serialize the GameObject laserPrefab which gets exposed in the Unity Editor in the Inspector tab when the Player GameObject is selected. laserOffset is a Vector3 that applies an offset to where the laser should be spawned at. In my use case, I apply an offset that is 0.8 units in the y direction from the player.

What is a Prefab?

A prefab is a file that is saved typically in the Prefabs folder that is used to spawn GameObjects during runtime (e.g. runtime = enabling play mode in the Unity Editor). Prefabs can be thought of as a template that contains components with preset variables that the instantiated game object will use the first time it is visible in the game world.

Spawning Lasers when space bar is pressed

In the above code, the laser gets fired whenever the space bar key is pressed and is called inside of the Update() function.

Applying upward velocity when a laser is spawned

In the Laser script, I use the transform.Translate function to apply an upward velocity inside of the Update function. This allows the laser to move on every tick for X units per second where X is the speed variable set.

Thanks for reading!