[U-Boot] U-Boot Graphics Library?

[Simon Glass]

Hi Wolfgang,

On Wed, Jan 16, 2013 at 11:46 AM, Wolfgang Denk <wd at denx.de> wrote:
> Dear Simon Glass,
>
> In message <CAPnjgZ12psS6sOnsuMU-VrrXWxS04Zb+grqqGUKNw2DTzBupag at mail.gmail.com> you wrote:
>>
>> We are currently using a very rudimentary graphics features attached
>> to U-Boot. It can only display bitmap images. We use this in Chromium
>> to composite a display for the various screens we need to display in
>> U-Boot. Unfortunately the graphics screens get quite large when using
>> multiple languages since they are pre-rendered.
>>
>> Is there any interest in a simply graphics library in U-Boot, that can
>> display things on the screen? We already have bitmap support, but
>> could perhaps add outline font support (e.g. freetype) as well. This
>> might allow display of simple boot menus or booting information. A
>> board could create a structure containing a list of things to display
>> (text, bitmaps) and pass it to the graphics library for rendering
>> using existing functions and the new font support.
>
> This sounds like a nice feature.  Initially.  Then I start wondering
> if this really belongs into a boot loader.  Instead of doing fancy
> graphics stuff, we should IMO rather focus on booting the OS of your
> choice really fast, and let this do the fancy GUIs.  Or?
>

The problem is that a major purpose of the GUIs is to allow installing
an OS from a USB stick/SD card, since the OS may have become corrupted
and unbootable. We have looked at keeping around a separate OS image
for this (e.g. in an available disk partition), but so far that hasn't
proved practical since that itself can be fairly easily overwritten
and we then have a doorstop.

The less fancy, the better, but consumers have certain expectations
that force us to make some efforts...there is already a single font in
U-Boot, but it's not good enough for multi-language pretty displays
unfortunately.

Regards,
Simon

> Best regards,
>
> Wolfgang Denk
>
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