koobas.hobune.stream
spawn a powerup in 2D platformer c#
This is my first project so please bear with me. I've managed to create a scene which works pretty well - it has floor, player, collisions, physics and some mechanics for decreasing health.
My problem stems from a powerup/powerdown mechanic. I have : 1 prefab (a question mark) which applies a random powerup/powerdown to the player. When player collides, it applies the affect for 5 secs. I have tested this code and works well (using switch statement for random affect).
I have looked everywhere and cannot find a good example to achieve my last part. This is to:
Spawn the prefab x number of times throughout the level just above the floor (floor is rectangle collider). The X position can be anything, but the Y value needs to be just above the floor.
I need the powerup/down prefab to not overlap anything (including itself) and it needs to be random - i.e. not using a hidden game object for spawn points.
The floor is on it's own layer which I thought could assist me ... psedo code I thought:
if (spawnpoint above floor_layer)
instantiate (powerup, random.range.x, floor_layer.y)
Any advice would be greatly appreciated on this. I looked at raycasting (haven't really been successful in implementing raycasting though), manual spawn points (not what I prefer).
End result should look like: 1) player starts level 2) as player runs through, powerups/downs appear throughout the level at ground level. 3) my powerup script destroys prefab after applying affect - should remain destroyed.
Is there a particular reason why you don't want to place spawn points manually for these powerups? It's a much simpler mechanic to implement and unless your levels are randomly generated there is no need to do this dynamically. You can always add a bunch of spawners in areas you think would be good candidates for power-ups, then randomly choose a subset of them. For example, you may have 10 spawn points but you only ever randomly choose 3 of them when the level starts.
Thanks for both of your responses.
@ThePunisher - I agree that spawn points will be easier and have considered it. $$anonymous$$y reason for not using them is that I plan the level to be very long and would prefer the powerups to spawn in different places each time - the player would hopefully have to replay the level numerous times and having pickups in different locations should add to a more varied game experience.
@Jopan - Thanks for the code - it's very similar to the one I'm using now. The pickups spawn under my platforms though - this is due to my platforms elevating throughout the scene so Y co-ords can vary alot. The code I would need will require a check to see if the ground is beneath the spawning X location - if spawnlocation.X > ground.y then spawn object, etc.
As a temporary stop gap I've created a different method of spawning - the powerups spawn well above the scene with a rigidbody and child object with another collider (due to the parent collider being a trigger). What happens is: Powerup spawns out of screen. Powerups drop down and land on platform. $$anonymous$$y current issue is trying to make the powerups not "slide" down the slopes in the level - they should drop and stay still ready for pickup.
Below is the simple code I'm using for this method which has potential with a little tweaking:
public class PudSpawnScript : $$anonymous$$onoBehaviour {
public GameObject pudPrefab;
public GameObject groundObject;
void Update () {
for (int i = 0; i < 10; i++) {
SpawnPud ();
}
}
private void SpawnPud ()
{
Instantiate (pudPrefab, new Vector3(Random.Range(-28, 200), 20), pudPrefab.transform.rotation) ;
}
using UnityEngine;
using System.Collections;
public class SpawnPowerUps : MonoBehaviour
{
public int numberOfPowerUps = 10; // How many power ups to spawn
public float minXSpawn = 0f; // The min x position that power ups can spawn
public float maxXSpawn = 10f; // The max x position that power ups can spawn
public float ySpawn = 1f; // The y position that all power ups will spawn
public GameObject powerUpPrefab; // The prefab of the power up to be spawned
void Start()
{
// Run code numberOfPowerUps amount of times
for (int i = 0; i < numberOfPowerUps; i++)
{
// Generate a random number between minXSpawn and maxXSpawn
float randomX = Random.Range(minXSpawn, maxXSpawn);
Vector2 spawnPosition = Vector2.zero; // Create a variable to store the spawn position being generated
spawnPosition.x = randomX; // Assign x to be our random x value
spawnPosition.y = ySpawn; // Assign y to our desired y position
// Instantiate our powerup at the spawn position with a default rotation
Instantiate(powerUpPrefab, spawnPosition, Quaternion.identity);
}
}
This won't solve the power ups not spawning on each other, but it does all the other stuff you want.
