started a clean program and reading up a little on the FFTW. dumped out a memblock of the normal image so far along with RGBA DWORD color values. All this has to be converted to heightmap float values using FFTW. The example FFTW that came with the DLL wrapper isn't correct for what we want looking at the output image. Will see how this all goes, there's more to it than I first thought looking at the reference material on google etc....
At the moment, my Heightmap to GameGuru converts a Normal image (or any HM image) to Heightmap using Blitzterrain and seems to come out well. See pics 1 and 2 below:
It will be a good comparison when I get the FFTW code working correctly for this project.
so for this, I will be using pointers to array elements like the C code.