Mesa (master): i965/gen6: Initial implementation of MSAA.

[Paul Berry]

Module: Mesa
Branch: master
Commit: 19e9b24626c2b9d7abef054d57bb2a52106c545b
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=19e9b24626c2b9d7abef054d57bb2a52106c545b

Author: Paul Berry <stereotype441 at gmail.com>
Date:   Sun Apr 29 21:41:42 2012 -0700

i965/gen6: Initial implementation of MSAA.

This patch enables MSAA for Gen6, by modifying intel_mipmap_tree to
understand multisampled buffers, adapting the rendering pipeline setup
to enable multisampled rendering, and adding multisample resolve
operations to brw_blorp_blit.cpp. Some preparation work is also
included for Gen7, but it is not yet enabled.

MSAA support is still fairly preliminary.  In particular, the
following are not yet supported:
- Fully general blits between MSAA and non-MSAA buffers.
- Formats other than RGBA8, DEPTH24, and STENCIL8.
- Centroid interpolation.
- Coverage parameters (glSampleCoverage, GL_SAMPLE_ALPHA_TO_COVERAGE,
  GL_SAMPLE_ALPHA_TO_ONE, GL_SAMPLE_COVERAGE, GL_SAMPLE_COVERAGE_VALUE,
  GL_SAMPLE_COVERAGE_INVERT).

Fixes piglit tests "EXT_framebuffer_multisample/accuracy" on
i965/Gen6.

v2:
- In intel_alloc_renderbuffer_storage(), quantize the requested number
  of samples to the next higher sample count supported by the
  hardware.  This ensures that a query of GL_SAMPLES will return the
  correct value.  It also ensures that MSAA is fully disabled on Gen7
  for now (since Gen7 MSAA support doesn't work yet).
- When reading from a non-MSAA surface, ensure that s_is_zero is true
  so that we won't try to read from a nonexistent sample.

---

 src/mesa/drivers/dri/i965/Makefile.sources         |    1 +
 src/mesa/drivers/dri/i965/brw_blorp.cpp            |   10 +-
 src/mesa/drivers/dri/i965/brw_blorp.h              |   30 ++-
 src/mesa/drivers/dri/i965/brw_blorp_blit.cpp       |  332 +++++++++++++++++---
 src/mesa/drivers/dri/i965/brw_context.h            |    8 +
 src/mesa/drivers/dri/i965/brw_defines.h            |    7 +
 src/mesa/drivers/dri/i965/brw_misc_state.c         |   33 +--
 src/mesa/drivers/dri/i965/brw_state.h              |    4 +
 src/mesa/drivers/dri/i965/brw_state_upload.c       |    2 +
 src/mesa/drivers/dri/i965/brw_wm_surface_state.c   |   16 +-
 src/mesa/drivers/dri/i965/gen6_blorp.cpp           |   44 ++--
 src/mesa/drivers/dri/i965/gen6_multisample_state.c |  102 ++++++
 src/mesa/drivers/dri/i965/gen6_sf_state.c          |   15 +-
 src/mesa/drivers/dri/i965/gen6_wm_state.c          |   12 +
 src/mesa/drivers/dri/i965/gen7_blorp.cpp           |   20 +-
 src/mesa/drivers/dri/i965/gen7_sf_state.c          |   14 +-
 src/mesa/drivers/dri/i965/gen7_wm_state.c          |   18 +-
 src/mesa/drivers/dri/i965/gen7_wm_surface_state.c  |   16 +
 src/mesa/drivers/dri/intel/intel_fbo.c             |   31 ++-
 src/mesa/drivers/dri/intel/intel_mipmap_tree.c     |   52 +++-
 src/mesa/drivers/dri/intel/intel_mipmap_tree.h     |   10 +-
 src/mesa/drivers/dri/intel/intel_tex_image.c       |    3 +-
 src/mesa/drivers/dri/intel/intel_tex_validate.c    |    3 +-
 23 files changed, 662 insertions(+), 121 deletions(-)

Diff:   http://cgit.freedesktop.org/mesa/mesa/diff/?id=19e9b24626c2b9d7abef054d57bb2a52106c545b