#57 How to use dsp primitive?

release 7.12
Sean Morrison
Richard Uschold

I can't find any documentation on the dsp primitive (displacement map) other
than a extremely brief definition which NAMES the required parameters, but
fails to define what they MEAN! The acceptable file format(s) are not given
either (neither .pix nor .bw work).

The documentation that came with the package is rather poor, with many
broken links and seems to be several versions old. I have version 7.12.2 for
Mac OSX.



  • Sean Morrison
    Sean Morrison

    Quite true, the DSP doesn't really have much in the way of documentation, at least not publicly available documentation. The problem with having a large complex CAD system is that the documentation is similarly large and complex (and just as prone to bugs and omissions). Asking is definitely the way to go, though.

    In brief, the DSP takes unsigned short (16-bit) integer data. Our various command-line data converters can help bring data in from pretty much any existing format, including image data, via various processing commands. If the data was in png image format, for example (which is basically 3-channel 8-bit integer data), the data could be prepared with a combination of 'png-pix', 'pix-bw', and 'cv'. This would be a path very similar to what is described for the EBM primitive here: http://brlcad.org/wiki/EBM

    If you type the 'in' command, it will prompt you for each parameter individually and that should help some. For the DSP, the main parameters are the width/length of the input data, width/length/height scaling factors, and whether to smoothly interpolate between cells. A wiki page similar to the EBM is needed for the DSP primitive (you're welcome to start one)!

  • Sean Morrison
    Sean Morrison

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