<html>
<head>
<base href="https://bugs.freedesktop.org/" />
</head>
<body><span class="vcard"><a class="email" href="mailto:idr@freedesktop.org" title="Ian Romanick <idr@freedesktop.org>"> <span class="fn">Ian Romanick</span></a>
</span> changed
<a class="bz_bug_link
bz_status_NEEDINFO "
title="NEEDINFO - GL_ARB_texture_float is half float only"
href="https://bugs.freedesktop.org/show_bug.cgi?id=88506">bug 88506</a>
<br>
<table border="1" cellspacing="0" cellpadding="8">
<tr>
<th>What</th>
<th>Removed</th>
<th>Added</th>
</tr>
<tr>
<td style="text-align:right;">Status</td>
<td>NEW
</td>
<td>NEEDINFO
</td>
</tr></table>
<p>
<div>
<b><a class="bz_bug_link
bz_status_NEEDINFO "
title="NEEDINFO - GL_ARB_texture_float is half float only"
href="https://bugs.freedesktop.org/show_bug.cgi?id=88506#c3">Comment # 3</a>
on <a class="bz_bug_link
bz_status_NEEDINFO "
title="NEEDINFO - GL_ARB_texture_float is half float only"
href="https://bugs.freedesktop.org/show_bug.cgi?id=88506">bug 88506</a>
from <span class="vcard"><a class="email" href="mailto:idr@freedesktop.org" title="Ian Romanick <idr@freedesktop.org>"> <span class="fn">Ian Romanick</span></a>
</span></b>
<pre>(In reply to kaillasse91 from <a href="show_bug.cgi?id=88506#c2">comment #2</a>)
<span class="quote">> I just found this old bug report :
>
> <a class="bz_bug_link
bz_status_RESOLVED bz_closed"
title="RESOLVED FIXED - Mesa 7.12-devel implementation error: unexpected format 0x822e in _mesa_choose_tex_format()"
href="show_bug.cgi?id=44039">https://bugs.freedesktop.org/show_bug.cgi?id=44039</a></span >
Oh. Yeah, that's the problem. Like I mentioned in one of the comments on that
bug, "the problem is that GEN4 can't do filtering on 32-bit float formats."
Your GM45 is GEN4. We could either not support floating point textures at all,
or we can give 16-bit formats when the application asks for GL_RGBA32F. It's
one of those "all solutions are bad" situations.
<span class="quote">> Is it not related to what I've found (silently fallback to 16 bits format
> when 32 bits asked) ?
>
>
> OpenGL vendor string: Intel Open Source Technology Center
> OpenGL renderer string: Mesa DRI Mobile Intel® GM45 Express Chipset
> OpenGL version string: 2.1 Mesa 10.5.0-devel (git-461103e 2015-01-18
> trusty-oibaf-ppa)
> OpenGL shading language version string: 1.20</span >
(In reply to kaillasse91 from <a href="show_bug.cgi?id=88506#c0">comment #0</a>)
<span class="quote">> My problem is that it does it silently instead of telling me that this
> format is unsupported so I can choose what to do.</span >
I think if you query GL_TEXTURE_RED_SIZE it will tell you the number of bits
actually used by the implementation. Skimming Mesa code, I'm pretty sure it
will return 16 if GL_RGBA16F was used and 32 if GL_RGBA32F was used.
Can you try that?</pre>
</div>
</p>
<hr>
<span>You are receiving this mail because:</span>
<ul>
<li>You are the QA Contact for the bug.</li>
</ul>
</body>
</html>