From: Marcus Sundberg <e94_msu@elixir.e.kth.se>
  To  : ggi-develop@eskimo.com
  Date: Wed, 12 Aug 1998 22:15:02 +0200

Re: LibGGI colormapping

> Marcus writes:
> 
> >  > date: 1998/08/12 08:08:34;  author: ajapted;  state: dead;  lines: +0 -0
> >  > Removed fillscreen.c files -- they were either 1) broken (WRT stride) or
> >  > 2) no faster than using DrawBox()
> >  
> >  You should have looked closer at those files.
> 
> Sorry, I got carried away :-(.  I will put it all back if you like, but
> maybe it would be better to optimize DrawBox for the width == (stride/Bpp)
> case ?

Yep, adding an optimized drawbox to the linear-* libs is better. Having a
fillscreen that does anything other than calling
drawbox(vis,0,0,GGI_MODE(vis)->virt.x,GGI_MODE(vis)->virt.y)
is pretty useless unless fillscreen can be HW accelerated.

> >  We should probably have some "altered range" fields too, like the
> >  X-targets do, so that targets can see when the palette has been
> >  changed, and what entries have been changed.
>
> I'm not following you here.  What exactly do you mean ?

Look at this code from display/X/mode.c:

        if (xhook->cmap && xhook->cmap_first<xhook->cmap_last) {

                int x;
                XColor xcol;
                for(x=xhook->cmap_first;x<xhook->cmap_last;x++)
                {
                        xcol.red  =xhook->colormap[x].r;
                        xcol.green=xhook->colormap[x].g;
                        xcol.blue =xhook->colormap[x].b;
                        xcol.pixel=x;
                        xcol.flags= DoRed | DoGreen | DoBlue ;
                        XStoreColor(xhook->display, xhook->cmap,&xcol);
                }
                xhook->cmap_first=256;
                xhook->cmap_last=0;
                XSetWindowColormap(xhook->display, xhook->window, xhook->cmap);
        }
With the new system xhook->colormap will be vis->palette, and what I
meant was that the cmap_first and cmap_last entries should be in the
ggi_visual struct too, and that the stub GGIsetpalvec (hmm, maybe we
should remove the "vec" from the internal names too, for consistency :)
should do:
        if ( start     < xhook->cmap_first ) xhook->cmap_first = start;
        if ( start+len > xhook->cmap_last  ) xhook->cmap_last  = start+len;

//Marcus
-- 
-------------------------------+------------------------------------
        Marcus Sundberg        | http://www.stacken.kth.se/~mackan
 Royal Institute of Technology |       Phone: +46 707 295404
       Stockholm, Sweden       |      E-Mail: e94_msu@e.kth.se