1) Change MatrixWV to matWorldView
2) Change MatrixWVP to matWorldViewProj
3) LightDirection isn't set, you'll have to define it. Most likely what you want to do is use the global sunlight, so put this at the top of the code:
Code:
extern float4 vecSunDir

And change LightDirection to vecSunDir in your code.

That should be it...
-Rhuarc

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