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        <tr>
          <th>Bug ID</th>
          <td><a class="bz_bug_link 
          bz_status_NEW "
   title="NEW - [10.5.5/10.6 regression, bisected] PBO glDrawPixels no longer using blit fastpath"
   href="https://bugs.freedesktop.org/show_bug.cgi?id=90839">90839</a>
          </td>
        </tr>

        <tr>
          <th>Summary</th>
          <td>[10.5.5/10.6 regression, bisected] PBO glDrawPixels no longer using blit fastpath
          </td>
        </tr>

        <tr>
          <th>Product</th>
          <td>Mesa
          </td>
        </tr>

        <tr>
          <th>Version</th>
          <td>unspecified
          </td>
        </tr>

        <tr>
          <th>Hardware</th>
          <td>Other
          </td>
        </tr>

        <tr>
          <th>OS</th>
          <td>All
          </td>
        </tr>

        <tr>
          <th>Status</th>
          <td>NEW
          </td>
        </tr>

        <tr>
          <th>Severity</th>
          <td>normal
          </td>
        </tr>

        <tr>
          <th>Priority</th>
          <td>medium
          </td>
        </tr>

        <tr>
          <th>Component</th>
          <td>Drivers/DRI/i965
          </td>
        </tr>

        <tr>
          <th>Assignee</th>
          <td>idr@freedesktop.org
          </td>
        </tr>

        <tr>
          <th>Reporter</th>
          <td>amonakov@gmail.com
          </td>
        </tr>

        <tr>
          <th>QA Contact</th>
          <td>intel-3d-bugs@lists.freedesktop.org
          </td>
        </tr></table>
      <p>
        <div>
        <pre>Starting from commit
<a href="http://cgit.freedesktop.org/mesa/mesa/commit/?id=536003c11e4cb1172c540932ce3cce06f03bf44e">http://cgit.freedesktop.org/mesa/mesa/commit/?id=536003c11e4cb1172c540932ce3cce06f03bf44e</a>
(i965: Add XRGB8888 format to intel_screen_make_configs), PBO-based
glDrawPixels may be unable to use the blitter "fast path" (apparently if the
application happens to get an XRGB window fbconfig).  It is rejected in
do_blit_drawpixels, because _mesa_format_matches_format_and_type returns false
for BGRX formats.  INTEL_DEBUG=perf,pix says:

do_blit_drawpixels
do_blit_drawpixels: bad format for blit
intelDrawPixels: fallback to generic code in PBO case

A repro is available at <a href="https://bugs.freedesktop.org/attachment.cgi?id=97258">https://bugs.freedesktop.org/attachment.cgi?id=97258</a>
(run as "./a.out 1000").

A possible workaround on the glx client side is to explicitely request
"GLX_ALPHA_BITS, 1" in the fbconfig, but is that really expected now?</pre>
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