# How to do smooth sprite movement on WP7 XNA

What's the correct technique for getting smooth sprite translations with XNA?

I've been developing the WP7 version of an app for a startup, so when we heard Angry Birds got ported today we wanted to check it out and compare. Angry Birds on WP7 had the sub-pixel blur problem with the bird sprites, whereas iPhone, Android, and Chrome all had smooth movement.

It sounds like they are accidentally rounding their sprite positions to the nearest pixel. This can happen automatically if you use the SpriteBatch.Draw() call that takes a Rectangle as the position of the sprite, since XNA's Rectangle uses integers instead of floats to represent position.
• You mean a Vector2, and yes. And to make sure that the floating point coordinates in the Vector2 struct are not being rounded to an integer value! – Olhovsky Jun 30 '11 at 6:11