Randomly create cubes on the surface of a sphere

Questions & Answers
1

I have a sphere. I want to hit it in random locations on the surface, and then mark each hit with a cube (to be replaced with an actual art asset later, obviously). How do I do this? I'm not having much luck, as my raycast-fu is weak. Here are the relevant bits of a script that's attached to the sphere:

var currentRuinsNumber = 0;
var randomRuinsVector : Vector3;

// Find places for ruins
while (currentRuinsNumber < numberOfRuins)
{
    randomVector = Vector3(Random.Range(-1.0, 1.1), Random.Range(-1.0, 1.1), Random.Range(-1.0, 1.1) );

    var ray : Ray = Ray(Vector3.zero, randomRuinsVector);
    var hit : RaycastHit;

    if (collider.Raycast(ray, hit, 100.0))
    {
        Debug.DrawLine (ray.origin, hit.point);
        // put a cube here
    }
    currentRuinsNumber++;
}
2

If your just trying to get a random point on a sphere then there is a builtin function for that. code straight from docs.

rigidbody.velocity = Random.onUnitSphere * 10;

cheers, Grant

3

You guys were right! I found some help elsewhere too and here's what works for me:

var numberOfRuins : int;
var ruinCount : int;
var minOriginDistance : float = 1.0;
var hit : RaycastHit;
while (ruinCount < numberOfRuins)
{
    // cast a random ray to see if we hit land
	randomVec = Random.onUnitSphere;
    if (Physics.Linecast(randomVec * 2, Vector3.zero, hit, 1 << 8))
    {
	    if (hit.point.magnitude > minOriginDistance)
	    {
	        // we hit land!
			obj = Instantiate(ruinPrefab, hit.point, Quaternion.identity);
			obj.transform.LookAt(hit.point + randomVec);
			ruinCount++;
		} 
    }
}
4

This will do exactly what you require. http://entitycrisis.blogspot.com/2011/02/uniform-points-on-sphere.html