If you are using labview, you can use the WPI Robotics Library's Arcade Drive VI.
This is the default VI, so the default labview code (essentially just the framework, basic or advanced) can be built and sent to the cRIO to have this working.
If you are going to use C/C++, you are going to have to implement a relatively simple formula. The way it is *usually* done is to take the Y axis and call it velocity, then call the x axis rotation.
A simple two motor example-
Code:
wR = velocity + rotation;
wL = velocity - rotation;