Need help with AI [2D]

Hello

1st part -
So, enemies should start coming from random points from outside the screen and pass somewhere close to the middle.
That means - Few Starting points outside of the screen and few ending points somewhere in the middle of the screen. But they shouldn't stop when they reach end point, they should just continue and when they go outside of the screen again they should get destroyed.
- Spawn enemies until Player killed 50 enemies

2nd part -
When enemies are traveling and if Player is in their line of sight they should start following the player, and when player exits their line of sight they should just continue going forward.



Have a nice day!
- FloatyPixel

 

start easy
make 2 empty gameobjects: topleft, topright
make "spawn" c# script

Code (CSharp):

1.  
2. //points for min/max spawn
3. public GameObject topleft, topright;
4. // spawn timer
5. public float spawntime;
6. //how much enemy
7. public int maxenemy;
8. //for timer, i cannot understand corutine well :)
9. float maxtime;
10. //your enemy prefab
11. public GameObject enemy;
12. void Start() {
13. maxtime = spawntime;
14. }
15. void Update () {
16. //minus time everyframe
17. spawntime -= Time.deltaTime;
18. if (spawntime < 0) {
19. //reset for new cicle
20. spawntime = maxtime;
21. //random point between topleft - topright
22. float rndX = Random.Range (topleft.transform.position.x, topright.transform.position.x);
23. //make position for spawn on top-line
24. Vector3 pos = new Vector3 (rndX, topleft.transform.position.y, 0);
25. //spawn enemy
26. Instantiate (enemy, pos, transform.rotation);
27. // -1 enemy
28. maxenemy-=1;
29. if (maxenemy <= 0) {
30. //you can destroy spawner or just disable it
31. destroy (gameobject);
32. }
33. }
34. }
35.  

make enemy prefab, i dont know, how you will move it. If enemy will run to the "somewhere" on green square (on my picture):

float rndPosX = Random.Range (-1, 1);
float rndPosY = Random.Range (-1, 1);
Vector3 pos = new Vector3 (rndPosX, rndPosY, 0);
//then find the direction between start end end (middle)
Vector3 dir = pos - gameobject.transform.position;
//if your enemy has rigibody2D, then
rigidbody2d.velocity = new Vector3 (dir.x, dir.y,0);
//maybe you should normalize vector dir for constant speed: dir = Vector 3.Normalize (dir)

for line of sight try. Physic2D.OverlapCircle, if player is in it, then switch Vector3 pos with player.transform.position.

 

Thank you! That helped me a lot

 

https://www.reddit.com/r/gamedev/comments/3q0yn8/here_is_some_free_unity_movement_ai_ive_made/

 

I did something really similar to this for a 2d game! Let me explain how I did it, it might give you some ideas (even though I agree that you should start simple!)

First, I use UnityEngine.Random.insideUnitCircle.normalized to randomly place an enemy on a circle. I then multiply this value with a value that is large enough to make sure that the enemies always spawn outside of the screen.

Next I took a random position in the center of the screen (using a similar method as above) and I subtracted this from the position of the enemy (and normalized the result) to get the direction from the enemy to the center.

Finally, I made the enemy move in that direction at a certain speed, until the enemy was outside of the screen. When the enemy was outside of the screen, I would reuse this enemy by simple calling the first 2 methods again (to position and give direction to the enemy).