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<p class="MsoNormal">Dear List, but hopefully/probably for the attention of Ken<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Our custom splotch representation generates an image on each rank, but to get certain effects right, we pass all the images back from ranks>0 to rank=0 and perform a post render step on rank 0 (pixel normalization). Then rank0 returns
the final image to paraview and all ranks N>0 return an empty (black) image.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">This means that the compositing step we do (inefficient because it is using MpiReduce and not binary swap or direct send - or any other nice stuff in IceT) is performed once, and then paraview does its own compositing step as well.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’d like to remove the duplicated compositing phase, but our image has no depth buffer information and so I need to tell paraview/IceT to do a composition of the images using a SUM operation rather than a z-buffer test.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">is it possible to do this? (from a representation?)<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">If it is not possible to override the compositing step from paraview, could I implement a compositing step like allReduce(MPI::SUMP_OP), but using iceT instead of just raw MPI as it might improve performance.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">We’d like to use>1024 GPUs to render some really big cosmological data and so the compositing will be expensive and doing it twice is naturally undesirable.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">many thanks for any clues (I may have asked this question a couple of years ago, but have forgotten the answer).<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">yours<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">JB<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Courier New";mso-fareast-language:EN-GB">--
<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Courier New";mso-fareast-language:EN-GB">John Biddiscombe, email:biddisco @.at.@ cscs.ch<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Courier New";mso-fareast-language:EN-GB"><a href="http://www.cscs.ch/"><span style="color:windowtext">http://www.cscs.ch/</span></a><o:p></o:p></span></p>
<p class="MsoNormal"><span lang="EN-US" style="font-size:10.0pt;font-family:"Courier New";mso-fareast-language:EN-GB">CSCS, Swiss National Supercomputing Centre | Tel: +41 (91) 610.82.07<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="IT-CH" style="font-size:10.0pt;font-family:"Courier New";mso-fareast-language:EN-GB">Via Trevano 131, 6900 Lugano, Switzerland | Fax: +41 (91) 610.82.82<o:p></o:p></span></p>
<p class="MsoNormal"><span lang="IT-CH"><o:p> </o:p></span></p>
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