Creating points on the edge of a sprite

Unity Engine
, ,
1

I am trying to create points on the edge of my 2d capsule, I show an example of what I am looking for in the image.
I need 30 points where I will instantiate objects; They will need to be placed on the edge of the capsule and arranged evenly, the design is organized so that I have 5left, 10top, 5right, 10bottom points
Can someone help me?

Screenshot (121)
Screenshot (121)1366×730 30.7 KB

Draft code:

using UnityEngine;

[ExecuteInEditMode]
public class Place : MonoBehaviour
{
    public int numberOfPoints = 30;
    public float circleRadius = 0.1f;

    private void OnDrawGizmos()
    {
        SpriteRenderer spriteRenderer = GetComponent<SpriteRenderer>();
        if (spriteRenderer == null)
        {
            Debug.LogError("SpriteRender is missing!");
            return;
        }

        if (spriteRenderer != null)
        {
            Bounds bounds = spriteRenderer.bounds;
            Vector3 center = bounds.center;
            Vector3 size = bounds.size;

            float angleStep = 360f / numberOfPoints;

            for (int i = 0; i < numberOfPoints; i++)
            {
                float angle = i * angleStep * Mathf.Deg2Rad;
                Vector3 direction = new Vector3(Mathf.Cos(angle), Mathf.Sin(angle), 0) * (size.x / 2);

                Gizmos.color = Color.red;
                Gizmos.DrawLine(center, direction);
                Vector3 circlePosition = center + direction;
                
                Gizmos.DrawWireSphere(circlePosition, circleRadius);
            }
        }
    }
}
2

If it’s for one item, just make the points by hand, save a prefab with those as child GameObjects.

If it’s for a bunch of these that are different in some mathematically-definable way, then it may be worth writing some code.

Otherwise, traditionally a “capsule” usually implies two circles connected by a tube… yours above looks more parabolic on its end.

But in any case, the same rules apply: you would write code to consider the linear perimeter, perhaps a generator function, first for the top straight part, one curve, then the bottom straight part going the opposite direction, then the other curve going the opposite direction.

Here’s a cheap and cheerful example of how I would start the process with a generator:

using System.Collections;
using System.Collections.Generic;
using UnityEngine;

// @kurtdekker - to demo using generators to make points
//
// To use: drop on empty GameObject sufficiently far ahead of a Camera
//
// tinker with the intervals and counts to get what you need
//

public class DemoGenerator : MonoBehaviour
{
	IEnumerable<Vector3> GeneratePoints()
	{
		// TODO: add whatever you want in here
		Vector3 position = Vector3.zero;

		// straight line
		int count = 10;
		for (int i = 0; i < count; i++)
		{
			position = new Vector3( i, 0);
			yield return position;
		}

		// now a half circle
		count = 10;

		float radius = 5;
		Vector3 center = position + Vector3.up * radius;

		for (int i = 0; i < count; i++)
		{
			float angle = (i * 180.0f) / count;

			Quaternion rotator = Quaternion.Euler(0, 0, angle);

			Vector3 offset = Vector3.down * radius;

			offset = rotator * offset;

			position = center + offset;

			yield return position;
		}

		/// etc...
	}

	// run it with a coroutine only so we can watch it
	IEnumerator Start ()
	{
		foreach( var position in GeneratePoints())
		{
			
			GameObject sphere = GameObject.CreatePrimitive( PrimitiveType.Sphere);

			Vector3 finalPosition = position + Vector3.forward * 10;

			sphere.transform.localPosition = finalPosition;

			yield return new WaitForSeconds( 0.2f);
		}
	}
}