nanogui: framebuffer endianess
Subject:
Re: [nanogui] framebuffer endianess
From:
Matthias Fuchs ####@####.####
Date:
22 Jan 2008 10:06:23 -0000
Message-Id: <200801221101.44150.matthias.fuchs@esd-electronics.com>
Hi Greg,
thanks for the hint. Thanks for the hint. Updating fblin16.c helped
a lot. Now I can play minesweeper with correct colors :-)
I will post a patch when pre-studies made it into a project.
(BTW, the minesweeper demo does not display the bombs hint from TextValue().
Neither on X11/i386 nor Framebuffer on PowerPC. So it's more lottery than strategy,
but that's another story :-)
Matthias
On Tuesday 22 January 2008 03:27, Greg Haerr wrote:
> > You've got a "BIGENDIAN" choice in config-file. Tried that?
>
> That won't affect framebuffer writes, instead it's used to
> determine whether to byteswap data read from disk.
>
>
>
> > I grep'ed over the complete code and did not find a place where wswap is
> > used
> to swap any access to the framebuffer. The swapping macros are only used
> when
> handling .bmp images.
>
> The 16bpp driver is src/drivers/fblin16.c. Write a swap macro
> before the word is written to the framebuffer and you should
> be on your way. See the nibble swapping in drivers/fblin4*.c
> for ideas.
>
> Regards,
>
> Greg
>
>
>
>
> For further testing I wrote a little tool that maps the framebuffer memory
> and runs over every pixel, does a 16bit read, swaps the pixel and writes it
> back.
>
> In the end my colors look as expected. So it's definetely a swapping issue.
