nanogui: Screen update methods
Subject:
RE: [nanogui] Re: Screen update methods
From:
Junior ####@####.####
Date:
25 May 2007 22:59:02 +0100
Message-Id: <CEBF7051E4C.00000470ejr@inbox.com>
> On Fri, May 25, 2007 at 07:36:11AM -0800, Junior wrote:
>> I understood that the idea of using an offscreen pixmap is such that I
>> can blit the entire screen and not draw individual pixels. Is this not
>> true?
>
> this is true, but only if you have hardware that supports an actual blit
> operation. the best you can get without hardware acceleration is an
> optimized block copy, which again, depending on your hardware, may end
> up copying pixel-by-pixel.
>
> your problem may be something as simple as needing vertical retrace
> synchronization before copying to the screen.
Thanks Aaron,
That actually crossed my mind and I was looking into how to implement it,
especially with a memory mapped framebuffer with no sync being used.
This seem to be a framebuffer driver addition than an application, yes?
I've done some tracing and what seem to be really killing me is this linear16_drawhorizline
function. That makes things worse and I haven't figured out when it's called and buy how.
It seems that drawing background color calles it but I'm not sure.
Thanks
--Jr.
