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<base href="https://bugs.freedesktop.org/" />
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<th>Priority</th>
<td>medium
</td>
</tr>
<tr>
<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW --- - GL_ARB_ES3_compatibility and std140 arrays"
href="https://bugs.freedesktop.org/show_bug.cgi?id=71741">71741</a>
</td>
</tr>
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<th>Assignee</th>
<td>idr@freedesktop.org
</td>
</tr>
<tr>
<th>Summary</th>
<td>GL_ARB_ES3_compatibility and std140 arrays
</td>
</tr>
<tr>
<th>QA Contact</th>
<td>intel-3d-bugs@lists.freedesktop.org
</td>
</tr>
<tr>
<th>Severity</th>
<td>major
</td>
</tr>
<tr>
<th>Classification</th>
<td>Unclassified
</td>
</tr>
<tr>
<th>OS</th>
<td>Linux (All)
</td>
</tr>
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<th>Reporter</th>
<td>sheffmail@mail.ru
</td>
</tr>
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<th>Hardware</th>
<td>x86 (IA32)
</td>
</tr>
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<th>Status</th>
<td>NEW
</td>
</tr>
<tr>
<th>Version</th>
<td>9.1
</td>
</tr>
<tr>
<th>Component</th>
<td>Drivers/DRI/i965
</td>
</tr>
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<th>Product</th>
<td>Mesa
</td>
</tr></table>
<p>
<div>
<pre>Created <span class=""><a href="attachment.cgi?id=89409" name="attach_89409" title="std140 array bug">attachment 89409</a> <a href="attachment.cgi?id=89409&action=edit" title="std140 array bug">[details]</a></span>
std140 array bug
It appears that mesa 9.1.7 incorrectly handles arrays inside uniform blocks
with std140 layout when GL_ARB_ES3_compatibility is used. I've attached a
sample program, build it with:
gcc std140_bug.c -o std140_bug -lX11 -lGL -lm
The program draws a triangle, rotation angle is taken from a uniform buffer in
vertex shader like this:
float angle = rotations[1];
This should access 2'nd array element, but instead it accesses 5'th element, as
a result triangle is rotated by 85 degrees (appears narrow) when it should be
rotated by 0 degrees (appear wide)
glxinfo:
OpenGL vendor string: Intel Open Source Technology Center
OpenGL renderer string: Mesa DRI Intel(R) Ivybridge Desktop x86/MMX/SSE2
OpenGL version string: 3.0 Mesa 9.1.7
OpenGL shading language version string: 1.30
uname -a:
Linux xxx 3.11.0-13-generic #20~precise2-Ubuntu SMP Thu Oct 24 21:07:45 UTC
2013 i686 i686 i386 GNU/Linux</pre>
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