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>
Also implement context member functions to optimize away those
flushes 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().
Instead, a new pipe_transfer object has to be created and mapped for
transferring data between the CPU and a texture. This gives the driver more
flexibility for textures in address spaces that aren't CPU accessible.
This is a first pass; softpipe/xlib builds and runs glxgears, but it only shows
a black window. Looks like something's off related to the Z buffer, so the
depth test always fails.
Quite a few util modules were maintaining a single vertex buffer over multiple
frames, and potentially reusing it in subsequent frames. Unfortunately that
would force us into syncrhonous rendering as the buffer manager would be
forced to wait for the previous rendering to complete prior to allowing the
map.
This resolves that issue, but requires the state tracker to issue a few new
flush() calls at the end of each frame.
Before, we were sometimes rendering into a stale texture because
st_finalize_texture() would discard the old texture and create a new one.
Moved st_update_framebuffer atom after texture validation so that we
can create a new renderbuffer surface if the texture changes.
Also, split texture validation into two parts: finalize_textures and
update_textures. Do finalize_textures first to avoid getting into the
situtation where we're doing a pipe->surface_copy() mid-way through
state validation.
Some debug code still in place, but disabled...
Create different temporary surfaces for CPU_READ/WRITE when needed (such as
for glReadPixels, glAccum, some glCopy/DrawPixels, glCopyTexSubImage, etc).
This fixes the case where the app calls SwapBuffers then calls glReadPixels
to read the front color buffer. We now keep track of when the front buffer
is a _logically_ copy of the back buffer (after SwapBuffers) and read from
the back color buffer instead of the front.
At this time there are no optimizations for directly blitting between
buffer objects and surfaces (always go through mappings).
glean pbo test passes now
Update the Makefiles and includes for the new paths.
Note that there hasn't been no separation of the Makefiles yet, and make is
jumping all over the place. That will be taken care shortly. But for now, make
should work. It was tested with linux and linux-dri. Linux-cell and linux-llvm
might require some minor tweaks.
pipe_get/put_tile_rgba() now use pipe->get/put_tile internally.
Also simplify the <format>_get/put_tile_rgba() helper functions and clean up
some inconsitencies in them.
