We need aditional meta data about the usage of the surface
in softpipe because we need to be able tell the diffrence
between PRIMARY and DISPLAY_TARGET surfaces.
When a buffer was mapped for write and no explicit flush range was provided
the existing semantics were that the whole buffer would be flushed, mostly
for backwards compatability with non map-buffer-range aware code.
However if the buffer was mapped/unmapped with nothing really written --
something that often happens with the vbo -- we were unnecessarily assuming
that the whole buffer was written.
The new PIPE_BUFFER_USAGE_FLUSH_EXPLICIT flag (based from ARB_map_buffer_range
's GL_MAP_FLUSH_EXPLICIT_BIT flag) allows to clearly distinguish the
legacy usage from the nothing written usage.
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.
allows the driver to overwrite buffer allocation, first step on the way
to making winsys interface internal to the drivers. state trackers and
the code above it will go through the screen
This will allow creating textures before a rendering context exists, for example.
Only implemented in i915 driver for now. i915pipe->texture_create() just
dispatches through to the i915screen->texture_create() to avoid state tracker
changes for now.
