Tip: Vector2.Normalize()
Vector2.Normalize() will fail silently if both members X and Y are zero. When it fails, the method will set X and Y to NaN (which stands for Not a Number.) Most operations using NaN will yield NaN so pretty soon all of your floating point values will become NaN!
When using Normalize() use the following pattern:
You may be tempted to use the following because it is most "mathematically" correct:
When using Normalize() use the following pattern:
Vector2 delta = new
Vector();
if (delta
!=
Vector2.Zero)
{
delta.Normalize();
}
Or:
Vector2 delta = new
Vector();
if
(delta.LengthSquared > 0)
{
delta.Normalize();
}
You may be tempted to use the following because it is most "mathematically" correct:
Vector2 delta = new Vector();
if (delta.Length > 0)
{
delta.Normalize();
}
But don't do it! The Length property causes a square root operation which is really expensive.
Labels: XNA
