|
That, I cannot give any insight into, I've not
worked within the DirectFB sdk, only used it. But I would think there should be
some reference to where the subsurface starts on the parent surface. But we
better check with the masters on this list :)
/Henric
----- Original Message -----
Sent: Friday, December 13, 2002 10:14
AM
Subject: [directfb-dev] Re: Help me
please! About 4bits pixel format.
Then, must I remeber whether the sub surface begins at odd
pixel? Or is
there some way to get this information from current data
structure?
Regards
James Su
Henric Andersson
wrote:
>Sorry about the previous mail, wrong button combo
:)
>
>
>
>>Hi,
>>So sorry to bother
you, but I really want to implement 4bits pixel
>>format for
DirectFB. The source code of DirectFB almost drives me crazy.
>>Could
you please give me some more hint or information?
>>Until now, I did
not understand the structure of DirectFB clearly,
>>especially the
surface memory management. In my understanding, a surface
>>may
occupy a block of memory itself or share a block of memory
with
>>other surface, ie. a sub surface. Am I right? Then, for
example if I
>>alloc a sub surface from an odd x coordination within
the father
>>surface, i.e. (3,4), the memory offset of the sub
surface will be 1.5
>>bytes, but it's impossible! There are many
other similar problems in
>>DirectFB to prevent me implementing 4bpp
format. But it is very
>>
>>
>
>It is possible to use uneven X coordinates. You
have to work at a bit level
>though. So, if you would highlight the
first pixel of a row, you would only
>manipulate the first 4 bits. The
next pixel would use the higher 4 bits of
>the same byte, the next (3rd)
pixel would use the lower 4 bits of the second
>byte, and so
on.
>
>Hope it
helps...
>
>/Henric
>
>
>
>
>
--
Info: To unsubscribe send a mail
to listar@directfb.org with
"unsubscribe directfb-dev" as
subject.
|
