Re: [announce 0/7] fbsplash - The Framebuffer Splash

On Wed, 9 Mar 2005 13:01:15 +0800, Antonino A. Daplas
[off-list ref] wrote:

On Tuesday 08 March 2005 09:57, Michal Januszewski wrote:

quoted

Fbsplash - The Framebuffer Splash - is a feature that allows displaying
images in the background of consoles that use fbcon. The project is
partially descended from bootsplash.

Unlike bootsplash, fbsplash has no in-kernel image decoder. Picture
decompression is handled by a userspace helper which provides raw image
data to the kernel. There is also no support for things like the silent
mode and progress bars, as these are best handled by userspace programs.

If splash support is really, really, really wanted in the kernel, it's probably better
to just add minimal Overlay support for the framebuffer.  If overlay is added, it
won't be necessary to modify fbcon and the drivers, just core fb.

We can have 3 levels of support.  In it's most basic form, we have the display
layer (what get's shown in your monitor) plus 2 buffers in system ram, the
primary layer (where the console output is written) and the overlay, the
static image in raw framebuffer format.  Then we replace the basic
framebuffer operations (imageblit, fillrect and copyarea) with ones that
will read the contents of both buffers, do basic raster ops (colorkey, alpha
blend, etc) before writing to the actual display buffer.

The next level is both buffers are in video ram. This will need basic driver
support, at least to subdivide the framebuffer memory to display, primary,
and overlay.  We can use the drivers accelerated drawing functions to
write to the primary layer, then use software to write the processed
contents to the display layer.

Finally, we can enable full hardware video overlay.

Another idea would be to build a console is user space. Think of it as
a full screen xterm. A user space console has access to full hardware
acceleration using the DRM interface.

-- 
Jon Smirl
jonsmirl@gmail.com


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