Messages in this thread | | | Date | Thu, 6 Mar 2003 09:25:21 +0100 | Subject | Re: [Linux-fbdev-devel] Re: FBdev updates. | From | Sven Luther <> |
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On Thu, Mar 06, 2003 at 04:05:32PM +0800, Antonino Daplas wrote: > On Thu, 2003-03-06 at 15:35, Sven Luther wrote: > > > > > > > And one (or two...) generic questions: why is not pseudo_palette > > > > u32* pseudo_palette, or even directly u32 pseudo_palette[17] ? > > > > > > pseudo_palette was originally designed to be a pointer to some kind of > > > data for color register programming. For example many PPC graphics cards > > > have a color register region. Now you could have that point to > > > > Does this correspond to the LUT i have in my boards ? > > > > BTW, what is the point in having a pseudo_palette if you can store > > the colors in the onchip LUT table. > > > > The hardware clut typically stores each color channel separately. In > software terms, this is akin to struct fb_cmap. The pseudo_palette, on > the other hand, is a pixel LUT, the contents of which can be directly > written to the framebuffer without it ever knowing the format at all, ie > it does not matter if it's RGB or YUV. This makes the upper layer > independent of the low-lever driver (at least in terms of colorspace > formats).
Ok, thanks, ...
Friendly,
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