Re: [Qemu-devel] [PATCH 4/7] xen: add framebuffer backend driver

[Anthony Liguori <anthony@codemonkey.ws>]

Gerd Hoffmann wrote:
>   Hi,
>
>   
>>>> +/* A convenient function for munging pixels between different depths */
>>>> +#define
>>>> BLT(SRC_T,DST_T,RSB,GSB,BSB,RDB,GDB,BDB)                        \
>>>> +    for (line = y ; line < (y+h) ; line++) {                \
>>>>         
>
>   
>>> There are similar conversion macros in the VGA code.  I don't know how
>>> practical it would be to reuse them but it's at least worth looking at.
>>>       
>> We created a file hw/pixel_ops.h to share code between vga.c and tcx.c,
>> probably it can be extended to serve Xen as well.
>>     
>
> Uhm, well, it isn't that easy.  Unifying that looks like a big job in
> itself.  pixel_ops.h as-is isn't very helpful for xen-framebuffer.  The
> xen-framebuffer macro isn't very useful to others.
>   

Okay, the xen-framebuffer macros aren't that big so it's not a huge 
deal.  Was worth looking into though.  Thanks!

Regards,

Anthony Liguori

> What IMHO would be most useful is a set of generic conversion functions,
> operating on scanline level, much like the ones created by
> vga_template.h, but without dependencies on vga.c internals.
>
> cheers,
>   Gerd
>
>