>>Let directx rotate/process all vertices..
IDirect3DDevice9.ProcessVertices (always run on CPU, can use SSE class optimizations)
>>access the rotated vertices in some buffer..
VertexBuffer.Lock
>>let directx draw all for me.
VertexBuffer.UnLock
IDirect3DDevice9.DrawIndexedPrimitive

>>or, write my own shader without using dx shader language.
??