Re: Adding an fb_sync() operation to fb_ops

On Sat, 2002-06-01 at 04:14, Geert Uytterhoeven wrote:

On Fri, 31 May 2002, James Simmons wrote:

quoted

quoted

Secondly (not related to the topic), I was wondering if we can change
the color value passed to fillrect and imageblit.  Presently, the
palette index is always passed regardless of the visual. Should the
color value passed be reflective of the framebuffer format instead?
Pass a palette index if pseudocolor, an RGB value for truecolor, etc.

Doing the latter will simplify the low-level drawing function and at the
same time, it will make the drawing functions more flexible -- ie,
possiblity of exporting to userspace.

We had this discussion sometime ago. We discovered it was just impossible
to handle all the possible different color formats in the higher levels.
We ended up with way to many #ifdefs. So it was decided to let the drivers
handle it instead. Actually if you wanted it to be useable to userland
then it makes even more sense to use the color map index instead. Think
about all the if() statements you would need in userland.

Userland can easily set up function pointers, depending on the used format
(for commonly used formats). Even for the generic case it can be done without
too much loss of efficiency using look-up tables, cfr. fbtest.

I think that's a nice idea.  We can add another fb_op (I know, another
one), something like:

static u32 XXXfb_getcolor(u32 index, struct fb_info *info)
{
	u32 color = 0;

	switch (info->var.bits_per_pixel) {
	case 8:
	     color = index;
	     break;
	case 16:
	case 24:
	case 32:
	     color = ((u32 *)(info->pseudo_palette[index]))
	     break;
	}
	
	return color;
}


Then in fbcon-accel.c, we can have something like:

	region.fg_color = info->fb_getcolor(attr_fgcol(p, c));
	region.bg_color = info->fb_getcolor(attr_bgcol(p, c));

This will simplify fbcon-accel and the drawing functions. 

Tony


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