This is a follow-on to commit c1a3b85280.
Note that (at this time) wherever _NEW_PROGRAM_CONSTANTS is set we're still
setting _NEW_PROGRAM so this won't really make any difference (for now).
There are two usage types of buffer CPU accesses:
One where we try to use the buffer contents for multiple draw commands in
a batch. (batch := sequence of commands that are flushed together),
like incrementally adding bitmaps to a bitmap texture that is reallocated
on flush.
And one where we assume we can safely overwrite the old buffer contexts, like
glTexSubImage. In this case we need to make sure all old drawing commands
referencing the buffer are flushed before we map the buffer.
This is easily forgotten.
Add wrappers for the most common of these operations. The first type is
prefixed with "st_no_flush" and the second type is prefixed with
"st_cond_flush", where "cond" indicates that we attmpt to only flush
if there is indeed unflushed draw commands referencing the buffer.
Prefixed functions are
screen::get_tex_transfer
pipe_buffer_write
pipe_buffer_read
pipe_buffer_map
Please use the wrappers whenever possible.
Signed-off-by: Thomas Hellstrom <thellstrom-at-vmware-dot-com>
The core reference counting code is centralized in p_refcnt.h.
This has some consequences related to struct pipe_buffer:
* The screen member of struct pipe_buffer must be initialized, or
pipe_buffer_reference() will crash trying to destroy a buffer with reference
count 0. u_simple_screen takes care of this, but I may have missed some of
the drivers not using it.
* Except for rare exceptions deep in winsys code, buffers must always be
allocated via pipe_buffer_create() or via screen->*buffer_create() rather
than via winsys->*buffer_create().
If only glUniform is called between two renderings, the const buffers weren't
getting updated. Need to set the _NEW_PROGRAM flag in st_upload_constants()
as that's the dirty flag set by glUniform.
Fixes glean tapi2 test.
Provide an actual definition of the pipe_buffer struct, containing
the parameters used to create the buffer, and its refcount.
Shift refcounting buffers out of the winsys interface, similar to
surfaces & textures.
Rework pipebuffer/ to reflect the fact these changes, and also Michel's
reworking of the buffer interface.
The properties of a buffer represented by struct pipe_buffer_handle are now
basically constant over its lifetime. The state tracker gets to deal with any
more complex buffer semantics it may need to provide.
