Generating scalar field for a sphere

Questions & Answers
1

The method I’m using now creates binary point values i.e. they are either empty or filled. I need a method for a smooth sphere.

	public Vector3 center;
	public float radius = 10.0f;
	public float GetValue(float x,float y,float z)
	{
		float distance = Vector3.Distance(new Vector3(x,y,z),center);
		if(distance < radius)
			return -1.0f;		
		return 1.0f;
	}

The value needs to be in the range of 1.0 to -1.0, 1.0 being full and -1.0 being empty.

2

I think this is what you are asking for:

if (distance >= radius) {
    return 1.0f;
}
else {
    return (distance / radius) * 2.0f - 1.0f;
}