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<body><span class="vcard"><a class="email" href="mailto:kenneth@whitecape.org" title="Kenneth Graunke <kenneth@whitecape.org>"> <span class="fn">Kenneth Graunke</span></a>
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<a class="bz_bug_link
bz_status_ASSIGNED "
title="ASSIGNED - GL_ARB_transform_feedback2 on i965 gen6"
href="https://bugs.freedesktop.org/show_bug.cgi?id=99842">bug 99842</a>
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<th>What</th>
<th>Removed</th>
<th>Added</th>
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<td style="text-align:right;">Status</td>
<td>NEW
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<td>ASSIGNED
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<td style="text-align:right;">Assignee</td>
<td>intel-3d-bugs@lists.freedesktop.org
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<td>kenneth@whitecape.org
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<b><a class="bz_bug_link
bz_status_ASSIGNED "
title="ASSIGNED - GL_ARB_transform_feedback2 on i965 gen6"
href="https://bugs.freedesktop.org/show_bug.cgi?id=99842#c1">Comment # 1</a>
on <a class="bz_bug_link
bz_status_ASSIGNED "
title="ASSIGNED - GL_ARB_transform_feedback2 on i965 gen6"
href="https://bugs.freedesktop.org/show_bug.cgi?id=99842">bug 99842</a>
from <span class="vcard"><a class="email" href="mailto:kenneth@whitecape.org" title="Kenneth Graunke <kenneth@whitecape.org>"> <span class="fn">Kenneth Graunke</span></a>
</span></b>
<pre>Looking at this again, we apparently never implemented Pause and
ResumeTransformFeedback() driver hooks...which meant that we actually failed to
restore the streamout buffer writing location during [Pause A -> Bind B -> ...
-> Bind A -> Resume A] situations.
Honestly, I think we forgot that this was a part of ES 3.0...there aren't any
failing tests for this in the CTS, so it looked like everything was working.
There is a failing Piglit test, which I'm guessing came about after we had done
ES 3.0 and moved on.
I remember looking at implementing GL_ARB_transform_feedback2 back in the day.
I saw the lack of MI_LOAD_REGISTER_MEM and figured Pause/Resume would be
painful to implement. Of course, I failed to notice that there's a command to
do this...but the hard part is that there isn't a register to read, making it
hard to obtain the value at Pause time.
Of course, this is part of ES 3.0, so we have to do it anyway. I've found a
solution that seems to work, and should fix those problems.
At that point, GL_ARB_transform_feedback2 only has one feature over and above
ES 3.0 - glDrawTransformFeedback(). However...that's easy. The mechanism for
the above bug fix makes this just work with no additional code.
So I think we can turn it on. I have no idea how well WebGL 2.0 will work...</pre>
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