Re: [Plplot-devel] x20c.c

[Andrew R. <ar...@ge...>]

>whatever).  Now in order to work with colour images in plplot you do need
>the appropriate colour pallette defined for cmap1, but the png format, for
>example, does allow for up to 256 different colours in a pallette.  (png
>format also has the truecolour alternative, but we must avoid that because
>plplot would not be able to work with it.) 

Is that /really/ true ? I must confess I have not looked at the code yet
(or for months), but I didn't think that plplot /was/ limited to 256
colours. my last look at the colourmap stuff made me think it could easily
cope with more than that. The current PNG driver is limited to 256 because
the 1.? versions of GD didn't support truecolour, but unless I am mistaken
plplot should be "open" enough to support more than 256 colours already.
16.5 million might be pushing it, but all the same...  Someone please
correct me if I am wrong.

>Andrew, I assume you haven't yet had a chance to implement a libgd-based
>image reading routine for x20c so I am just going to go ahead on my own.

I was sleeping while most of these discussions were going on - you forget,
I am on the other side of the world from most of you guys :-) I was going
to have a look at it today and see what was to be done. Let me know what
progress you're making and let see what happens. 

Apart from anything else, I have to build GD 2.0.1. I downloaded it last
night, and tried a build but ran into problems. Since GD 1.8.? they
clobbered the 8.3 naming conventions, so I had to remake the make file
fixing up the problems, then to slow things down even more, I discovered
that somehow (how or why it happened, I have NO idea) I no longer have
libpng's header files so could not recompile the new GD. Once I get those
headers back I will have another go at rebuilding the library. 

- Andrew