Re: Re: [PATCH]: image.depth fix to accomodate monochrome cards

On 11 Jan 2003, Antonino Daplas wrote:

On Sat, 2003-01-11 at 03:43, Geert Uytterhoeven wrote:

quoted

On Fri, 10 Jan 2003, James Simmons wrote:

quoted

   I'm just not to crazy about the depth equal zero thing. I just pitcure 
developers having a hard time with it.

Monochrome color expansion just works differently: it expands the zeroes and
ones in a bitmap based on fg_color and bg_color, while image drawing draws an
image containing colormap indices to the frame buffer.

Do you have a better suggestion?

If James is a bit skeptical about this, how about doing it this way:

If image.fg_color and image.bg_color == 0, then each byte of image.data
is an index to the pseudo_palette, or the actual pixel, whatever the
case may be.  Otherwise, image.data is a monochrome bitmap that should
be expanded using fg_color and bg_color.

No other changes will be needed except that mono cards have to test for
fg_color and bg_color, and we need to memset the fb_image structure to 0
in fb_set_logo(). Non-mono cards will continue testing for image.depth.

Do you think this will work?  The only problem I can think of is a color
expansion request where both bg and fg is 0.

And that can happen, try <ESC>[31m<ESC>[41m to set both to red.

Or to totally eliminate the above possibility, add an extra field in
struct fb_image to denote color expansion vs logo drawing.  Again, only
mono cards will need to do this test.

Ugh, why invent a new field if we can use an existing field? depth == 0 is
invalid for image blitting anyway.

Gr{oetje,eeting}s,

						Geert

--
Geert Uytterhoeven -- There's lots of Linux beyond ia32 -- geert@linux-m68k.org

In personal conversations with technical people, I call myself a hacker. But
when I'm talking to journalists I just say "programmer" or something like that.
							    -- Linus Torvalds



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