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<th>Bug ID</th>
<td><a class="bz_bug_link
bz_status_NEW "
title="NEW - [gallium] glCopyPixels is affected by enabled texture state"
href="https://bugs.freedesktop.org/show_bug.cgi?id=96943">96943</a>
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<th>Summary</th>
<td>[gallium] glCopyPixels is affected by enabled texture state
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<th>Product</th>
<td>Mesa
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<th>Version</th>
<td>git
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<th>Hardware</th>
<td>Other
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<th>OS</th>
<td>All
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<th>Status</th>
<td>NEW
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<th>Severity</th>
<td>normal
</td>
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<th>Priority</th>
<td>medium
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<th>Component</th>
<td>Mesa core
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<th>Assignee</th>
<td>mesa-dev@lists.freedesktop.org
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<th>Reporter</th>
<td>imirkin@alum.mit.edu
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<th>QA Contact</th>
<td>mesa-dev@lists.freedesktop.org
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<pre>The recently rewritten copy-pixels test has exposed some failures in st/mesa.
When there's an overlapping copy (among other conditions), the operation
becomes a fb read + draw of that texture with the current fragment shader
modified in the same way as glDrawPixels does it. (So this problem might extend
itself to glDrawPixels as well).
Doing a glDisable(GL_TEXTURE_2D) before the glCopyPixels() call in the piglit
fixes the issue. Effectively that texture is being multiplied with the copied
data, whereas from what I can tell, it shouldn't be. I think the multiplication
comes from the ff-generated shader.
[An alternative is that the piglit test and i965 are wrong and what gallium is
doing is correct. I don't think that's the case, since the only disagreement is
on the overlapped copy.]</pre>
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