Question

When you need to have very small objects, say that contains 2 float property, and you will have millions of them that aren’t gonna be ‘destroyed’ right away, are structs a better choice or classes?

Like in xna as a library, there are point3s, etc as structs but if you need to hold onto those values for a long time, would it pose a performance threat?

Answer 1

Contrary to most questions about structs, this actually seems to be a good use of a struct. If the data it contains are value types, and you are going to use a lot of these, a structure would work well.

Some tips:

:: The struct should not be larger than 16 bytes, or you lose the performance advantages.

:: Make the struct immutable. That makes the usage clearer.

Example:

public struct Point3D {     public float X { get; private set; }    public float Y { get; private set; }    public float Z { get; private set; }     public Point3D(float x, float y, float z) {       X = x;       Y = y;       Z = z;    }     public Point3D Invert() {       return new Point3D(-X, -Y, -Z);    }  }