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Alphaomega86
05-04-2014, 09:54 AM
Hey,

i am currently stuck on a problem, and i do not really know where it can be.
I think my fourier transformation is somehow wrong, currently, i have got those texture outputs:

First of all - Textures which seem to be right:
Static Phillips Spectrum combined with Gaussian Random values:
1290

Animated Phillips Spectrum combined with Gaussian Random values for choppy water effect at x axis:
1291

Animated Phillips Spectrum combined with Gaussian Random values for choppy water effect at z axis:
1292

Animated Phillips Spectrum combined with Gaussian Random values for wave heights:
1293


And now the textures which seem to be wrong:
Pre-Computed Butterfly Texture for faster computation of FFT in shader:
1294
In the R and G channels, there are stored the indices and in the B and A channels there are the
weightes.

(The background is red! This has nothing to to with the texture. Red areas are transparent.)


The computed FFT Wave texture for the wave heights is also wrong.

I would be really happy if someone can tell me, where the bug might be. I think it is in the
Fast Fourier Transformation, but i am not really sure.

- Daniel

Alphaomega86
05-04-2014, 10:00 AM
Here is my current butterfly texture with black background:
1295

And here is my current FFT texture for wave heights:
1296

As you may see, the FFT texture is absolutely wrong!