[GRASS-dev] Re: numeric-numpy-scipy for graphs?

[Michael Barton]

On 4/24/07 1:47 AM, "Glynn Clements" <glynn at gclements.plus.com> wrote:

> Not unless you're planning on using the BMP format (which means
> eliminating g.pnmcomp); it doesn't work with other formats.

OK. I missed the BMP part.

> 
> [Essentially, the image format needs store the actual image data as
> raw 32-bit pixels, which rules out both PNG and PPM/PGM. 32-bpp BMP is
> just that: a 54-byte header followed by raw 32-bit pixels. TGA and PAM
> might also be viable.]
> 
> On that subject, you really should look into eliminating g.pnmcomp.
> AFAICT, wxWidgets doesn't feature blending (although it should be able
> to do compositing with binary mask), but you may be able to use e.g.
> PIL for that. Performing compositing internally would save on I/O when
> enabling, disabling and re-ordering existing layers.

We're already doing internal compositing with the barscale/legend overlays,
using PseudoDC's. And I think that it is pretty easy to draw with a
transparent background with other DC's. I also see several ways to get
translucency in the demo. would mean reworking the rendering engine, but
probably worth it in the end.

Michael

__________________________________________
Michael Barton, Professor of Anthropology
School of Human Evolution & Social Change
Center for Social Dynamics & Complexity
Arizona State University

phone: 480-965-6213
fax: 480-965-7671
www: http://www.public.asu.edu/~cmbarton