<div>That's really interesting, for me the ProjectedTetra was so time consuming I ended up rendering only one slice of my volume so I could at least see some output. I do have many variations in opacity, my dataset is of a chest (I don't have much 'dead' space around the organs), so it sounds like this may really be a bad use of ProjectedTetra.
</div>
<div> </div>
<div>All my output is interactive, fixed point/3d texture have been pretty decent when it comes to responsiveness, except if the camera moves too close to the volume. The ray cast mapper looks the 'nicest' but it really takes too long to be used interactively for me. I was hoping that the responsiveness of ProjectedTetra would be good once ready for display, but it actually had the worst interactivity out of the bunch, even with one slice. Besides the opacity issue, I believe the ray cast mapper etc have built in functions to reduce the quality of the rendering while the user is interacting, which is very nice.
</div>
<div> </div>
<div>Thanks for sharing your experience,</div>
<div>Mark</div>
<div> </div>
<div><br><br> </div>
<div><span class="gmail_quote">On 2/7/06, <b class="gmail_sendername">Randall Hand</b> <<a href="mailto:randall.hand@gmail.com">randall.hand@gmail.com</a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">The last dataset I used was a 512-cube, stored as a vtkImageData I believe. One thing that greatly effects rendering time is the level of opacity you have. in my case, I had large regions of the space that were going to be completely transparent (accumulated opacity =
0.0), with only a small fireball in the center to render. If I adjusted my transfer function so that larger regions were rendered, then the render time increased.<br><br>Using a fixed transfer function that rendered only the small portion of the dataset I wanted to see, the FixedPoint mapper was abysmal at about 30 minutes per frame, and the ProjectedTetra mapper works in about 6 minutes (with the DataSetTriangleFilter time included). All of my stuff is non-interactive, being dumped directly to PNG images on disk.
<div><span class="e" id="q_10945c5bd4f67f86_1"><br><br>
<div><span class="gmail_quote">On 2/7/06, <b class="gmail_sendername">Mark Wyszomierski</b> <<a onclick="return top.js.OpenExtLink(window,event,this)" href="mailto:markww@gmail.com" target="_blank">markww@gmail.com</a>
> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">
<div>Hi Randall, Faith,</div>
<div> </div>
<div>I gave vtkProjectedTetrahedraMapper a try for the first time today but I experienced the longest render times with it out of any of the other mappers. I'm wondering what your input data being rendered is? Mine is a vtkImageData volume with dimensions of 256x256x56. The fixed point mapper or 3d texture mapper give me the fastest results.
<br> </div>
<div>Mark<br> </div>
<div><span>
<div><span class="gmail_quote">On 2/6/06, <b class="gmail_sendername">Randall Hand</b> <<a onclick="return top.js.OpenExtLink(window,event,this)" href="mailto:randall.hand@gmail.com" target="_blank">randall.hand@gmail.com
</a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">I think the best results will actually come from using the vtkProjectedTetrahedraMapper - <a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.vtk.org/doc/release/5.0/html/a01919.html" target="_blank">
http://www.vtk.org/doc/release/5.0/html/a01919.html</a><br><br>I've pretty much tried them all. The vtkVolumeRayCastMapper took about an hour to generate an image for me, the vtkFixedPointRayCastMapper cut it down to about 30 minutes. The vtkProjectedTetrahedraMapper takes the cake, however, at a whopping 5 minutes. Unfortunately, it does take alot more memory as it requires you to "tetrahedralize" your mesh.
<div><span><br><br>
<div><span class="gmail_quote">On 2/6/06, <b class="gmail_sendername"><a onclick="return top.js.OpenExtLink(window,event,this)" href="mailto:flin@enders.tch.harvard.edu" target="_blank">flin@enders.tch.harvard.edu</a></b>
<<a onclick="return top.js.OpenExtLink(window,event,this)" href="mailto:flin@enders.tch.harvard.edu" target="_blank">flin@enders.tch.harvard.edu </a>> wrote:</span>
<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid">Hello all,<br><br>I need some advice on how much imporvement the<br>vtkFixedPointVolumeRayCastMapper will make vs. regular
<br>vtkVolumeRayCastMapper ? I'm doing volume rendering of roughly<br>250x80x150 voxels, and the speed is unacceptable. Any suggestions on how<br>to speed up? Specifically, how to use hardware to accelerate it?<br><br>
Thanks.<br><br>/faith<br><br><br>_______________________________________________<br>This is the private VTK discussion list.<br>Please keep messages on-topic. Check the FAQ at: <a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.vtk.org/Wiki/VTK_FAQ" target="_blank">
http://www.vtk.org/Wiki/VTK_FAQ </a><br>Follow this link to subscribe/unsubscribe:<br><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.vtk.org/mailman/listinfo/vtkusers" target="_blank">http://www.vtk.org/mailman/listinfo/vtkusers
</a><br></blockquote></div><br><br clear="all"><br></span></div><span>-- <br>Randall Hand <br>Visualization Scientist, <br>ERDC-MSRC Vicksburg, MS<br>Homepage: <a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.yeraze.com/" target="_blank">
http://www.yeraze.com</a> </span><br>_______________________________________________<br>This is the private VTK discussion list.<br>Please keep messages on-topic. Check the FAQ at: <a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.vtk.org/Wiki/VTK_FAQ" target="_blank">
http://www.vtk.org/Wiki/VTK_FAQ</a><br>Follow this link to subscribe/unsubscribe:<br><a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.vtk.org/mailman/listinfo/vtkusers" target="_blank">http://www.vtk.org/mailman/listinfo/vtkusers
</a><br><br><br></blockquote></div><br></span></div></blockquote></div><br><br clear="all"><br>-- <br>Randall Hand<br>Visualization Scientist, <br>ERDC-MSRC Vicksburg, MS<br>Homepage: <a onclick="return top.js.OpenExtLink(window,event,this)" href="http://www.yeraze.com/" target="_blank">
http://www.yeraze.com</a> </span></div></blockquote></div><br>