texpict...

Hi!

I know that there has been a thread about bumpmaps not long ago. But I found
that Simon Crone has implemented a texpict modifier for an old version of
radiance. Is there anybody out there working with this and current radiance
releases? And why has this not been added to the official radiance code
branch?

I need some kind of bump-mapping, as I have a large model of a church with
some more detailed elements. There are reliefs on parts of the building which
exist in their geometry, but I don't want to model the relief :wink: BTW, this
would make the model too large, too.

So I will have to use colorpict for now... but I don't really like this... We
have all those nice bumpmap features in our modeling software, and now I have
to tell the others that I work with mapped images... :wink:

BTW, any hints regarding black/white-images as colorpict-maps?

Thank you, CU, Lars.

From: "Lars O. Grobe" <[email protected]>
I know that there has been a thread about bumpmaps not long ago. But I found
that Simon Crone has implemented a texpict modifier for an old version of
radiance. Is there anybody out there working with this and current radiance
releases? And why has this not been added to the official radiance code
branch?

I need some kind of bump-mapping, as I have a large model of a church with
some more detailed elements. There are reliefs on parts of the building which
exist in their geometry, but I don't want to model the relief :wink: BTW, this
would make the model too large, too.

So I will have to use colorpict for now... but I don't really like this... We
have all those nice bumpmap features in our modeling software, and now I have
to tell the others that I work with mapped images... :wink:

What's wrong with the "texdata" primitive? You'll have to convert your bump maps to ASCII data files. The in-memory size is the same as if the input were from a picture. The reason I didn't use pictures to describe the surface normal perturbation map is because they don't support negative values. What form is your input? If they're height fields, then you'll have to derive surface normal perturbations from these. I never liked or supported the use of height fields for bump maps, because there is no definitive mapping from a height field to a surface normal map, which is what you really want for this type of texture.

BTW, any hints regarding black/white-images as colorpict-maps?

Just use the colorpict map with "grey grey grey" as the modifier functions. If you don't like using 3x as much memory as single-channel data, then you'll have to convert your data to ASCII again and use the brightdata primitive.

-Greg

Lars O. Grobe wrote...

I know that there has been a thread about bumpmaps not long ago. But I found

that Simon Crone has implemented a texpict modifier for an old version of
radiance. Is there anybody out there working with this and current radiance

releases?

I have put up a copy of Simon Crone's source patches updated (by Terry Mc
Minn) for Radiance 3.4.1 at
http://puffin.curtin.edu.au/~mcminn/simon_crone.zip

Regards

Terry Mc Minn
Head of Emerging Technologies and Technical Services
School of Architecture, Construction and Planning
Curtin University of Technology
GPO Box U 1987
Perth 6845
Western Australia
Email: [email protected]
CRICOS Provider Code: 00301J