Jesse Towner

Just wondering how many other people out there are finding that XNA numerical classes/structures fall a little short of their needs and therefore are writing their own

For us, we needed to give our scene graph objects a coordinate frame where the rotation, scale, and translation transformation components are kept separate from one another; this is something similar to what is described in the book 3D Game Engine Architecture (

XNA didn't quite fulfill this niche, which is understandable as I imagine one constraint during its design was to make it easier to use.

So, in the end, I'm thinking about writing my own 3x3 matrix struct, and my own Transform struct (which represents the above mentioned coordinate frame construct). Has anyone run into any problems integrating their owns numerics with XNA's

Re: XNA Framework Anyone else rolling their own numerics?

Shawn Hargreaves - MSFT

Is there any reason (other than perhaps perf) why you couldn't build this kind of abstraction on top of the XNA math primitives

If people are finding a need to roll their own math from scratch, I'd like to understand why that is and what exactly we might be missing from the framework.

Re: XNA Framework Anyone else rolling their own numerics?

Bill Reiss

Well it's not quite the same thing, but I felt a need to create my own Rectangle struct that uses floating point numbers instead of ints. It made it easier to interpolate values when smoothly scrolling and moving sprites.