<div dir="ltr"><div class="markdown-here-wrapper" style="font-family:Verdana,Arial,sans-serif;color:rgb(11,83,148)"><p style="margin:0px 0px 1.2em!important">Hi Elvis,</p>
<p style="margin:0px 0px 1.2em!important">The ImageSampleDistance property was left out when coming up with the new OpenGL2 volume mapper to avoid an additional step of rendering the volume to an FBO and then using the texture to compute the scaling. This simplifies the code path and reduces the extra performance overhead. The documentation could have been better on this. We'll update it.</p><p style="margin:0px 0px 1.2em!important">That being said, do you have a specific use case for ImageSampleDistance? We could explore options for adding the feature back in.</p><p style="margin:0px 0px 1.2em!important">Thanks,<br>Sankhesh</p>
<div title="MDH:SGkgRWx2aXMsPGRpdj48YnI+PC9kaXY+PGRpdj5UaGUgSW1hZ2VTYW1wbGVEaXN0YW5jZSBwcm9w
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> I was digging through the code trying to understand how the<br class="gmail_msg">
> auto-adjustment of sample distance and image sample distance takes<br class="gmail_msg">
> place in the GPU volume ray cast mapper. From the looks of it, the<br class="gmail_msg">
> ImageSampleDistance is not respected by this mapper, even in the<br class="gmail_msg">
> non-automatic case, or am I missing something?<br class="gmail_msg">
<br class="gmail_msg">
Sorry, with "non-automatic case" I mean when AutoAdjustSampleDistance is Off.<br class="gmail_msg">
<br class="gmail_msg">
Elvis<br class="gmail_msg">
<br class="gmail_msg">
><br class="gmail_msg">
> The only role ImageSampleDistance seems to play for this mapper is<br class="gmail_msg">
> when the reduction factor is calculated (when auto-adjustment is<br class="gmail_msg">
> turned off):<br class="gmail_msg">
><br class="gmail_msg">
>   if ( !this->AutoAdjustSampleDistances )<br class="gmail_msg">
>   {<br class="gmail_msg">
>     this->ReductionFactor = 1.0 / this->ImageSampleDistance;<br class="gmail_msg">
>     return;<br class="gmail_msg">
>   }<br class="gmail_msg">
><br class="gmail_msg">
> Elvis<br class="gmail_msg">
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</blockquote></div></div><div dir="ltr">-- <br></div><div data-smartmail="gmail_signature"><div dir="ltr"><div class="inbox-markdown-here-wrapper" style="font-family:'proza libre',sans-serif;color:rgb(0,56,107)"><h5 id="inbox-sankhesh-jhaveri" style="margin:1.3em 0px 1em;padding:0px;font-size:1.1em;border-bottom-width:1px;border-bottom-style:solid;border-bottom-color:rgb(238,238,238);font-weight:bold;color:rgb(11,65,148)">Sankhesh Jhaveri</h5>
<h6 id="inbox--sr-research-development-engineer-kitware-http-www-kitware-com-518-881-4417" style="margin:1.3em 0px 1em;padding:0px;font-size:1em;color:rgb(11,83,148);font-family:'open sans',sans-serif;font-weight:normal"><em>Sr. Research & Development Engineer</em> | <a href="http://www.kitware.com/">Kitware</a> | (518) 881-4417</h6>
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