-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

Michel Dänzer wrote:
> On Wed, 2005-08-24 at 09:18 -0600, Brian Paul wrote:
> 
>>1. The location of the object in memory (perhaps the framebuffer has
>>    to be at the start of memory).
>>2. Particular byte/word alignments
>>3. Can we use VRAM and/or AGP memory for the object?
>>4. Can the object can be lost asynchronously (Pbuffers)?
>>... plus others I'm surely forgetting or not aware of.
> 
> Yes, I think these and maybe more should be handled via parameters when
> allocating a memory object. What I'm not sure is whether it's better to
> specify these specific but HW-dependent attributes or maybe some kind of
> abstract attributes (can be rendered to/from / scanned out / ...) which
> are then translated into specific constraints by a HW specific part of
> the memory manager. I'm leaning towards the latter.

That's what the BUFFLAG_ bits in memory_buffer.h were for.  When a
memory pool is created, the driver specifies a set of attributes for it.
 For example, cards like the G400 that can put the depth buffer in AGP
memory would have (BUFFLAG_DEPTH_BUFFER | BUFFLAG_STENCIL_BUFFER |
BUFFLAG_TEXTURE | BUFFLAG_COMMAND) for the AGP pool.  A card like the
R200 that can't put the depth buffer in AGP but can pull vertex data
from AGP would have (BUFFLAG_TEXTURE | BUFFLAG_VERTEX | BUFFLAG_COMMAND).

When an object is associated with a region ID (*not* when it is
committed to memory, see my other post) these bits are associated with
it.  The allocator then searches for a pool that meets all the
requirements.  Note that per-region requirements are only kept (or
needed) within the user-mode driver.  Since the kernel doesn't make any
decisions about where to put an object, it doesn't care.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v1.2.6 (GNU/Linux)

iD4DBQFDDJh2X1gOwKyEAw8RAj5vAJi8jT6pmLFPlPIRdvNCBqeoKV0yAJ9fvPo+
U7X5nlyIKYoeXL6tECfjfQ==
=X1VX
-----END PGP SIGNATURE-----


-------------------------------------------------------
SF.Net email is Sponsored by the Better Software Conference & EXPO
September 19-22, 2005 * San Francisco, CA * Development Lifecycle Practices
Agile & Plan-Driven Development * Managing Projects & Teams * Testing & QA
Security * Process Improvement & Measurement * http://www.sqe.com/bsce5sf
--
_______________________________________________
Dri-devel mailing list
[email protected]
https://lists.sourceforge.net/lists/listinfo/dri-devel

Reply via email to