I'm on Chapter 4 with a problem...
On pg 74, the book discusses making Transformations, as well creating a DrawRectangle method. I got up to pg. 78, where it tells me to put in the "world=Matrix.Identity;" and the "DrawRectangle(ref world);" When I went to compile and run, I got this error:
A valid vertex declaration must be set on the device before any draw operations can be performed.
*This was attached to the graphics.GraphicsDevice.DrawUserIndexedPrimitives method call code.*
Assuming I did write down everything right, well up to a point, what did I miss, and how do I fix the problem?