Enemies and Collision Detection
For today’s article, I’ll be going over how an Enemy is created and how Unity handles collisions using onTriggerEnter function. To create an enemy, I simply created a 3d cube in the scene, applied a red material on the cube, and named it Enemy. Next, I attached an Enemy script and applied the following behavior below:
In the above code, I use the Translate function to move the enemy from its starting position downwards 4 meters per second. Next, I check if the enemy reaches the bottom of the screen. If it does, I teleport the enemy back up to the top of the screen and set a random x position between the left and right edge of the screen.
Triggering Collisions
Behind the scenes, Unity handles the logic of when 2 game objects overlap with one another. In order for Unity’s collision system to take into effect, a Rigidbody component needs to be attached to the Laser game object prefab. Applying a Rigidbody component to a game object enables Unity’s physics system for that game object.
Also set Is Trigger to true for the laser
Lastly, Unity’s Monobehaviour class has a function we can implement named onTriggerEnter(Collider other) where it gets called whenever a collision is detected between 2 game objects. In the below code:
I check if the other collider is a game object that has the tag Laser.If the above is true:
- Destroy the laser game object
- Destroy the enemy game object
Final Result
To view the full source, please visit: https://github.com/hlimbo/Space-Shooter-Tutorial
Thanks for reading!
