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Hi- We're interested in using Chimera to prepare POVray files for a movie to be shown on a hemispherical dome. The first part of the movie will be a 360 degree rotation of a DNA/drug complex showing water occupancy around the drug, and the second half will come from an AMBER MD trajectory. We've figured out the content and rendering. The two remaining issues are that the camera must be changed from "perspective" to "omnimax" (fisheye), and the extensive rendering time that will be required for the large system at very high resolution (4096x4096). Here is our plan: 1. Use a command-line script to rotate the system and export the scene to x3d files. 2. Use per-frame scripting in MD movie to export each trajectory frame to x3d files. 3. Use x3d2pov to translate into *.pov files. 4. Change the camera from perspective to omnimax in each .pov file. 5. Render the individual images in parallel on our cluster using povray (different version than the one that ships with Chimera). 6. Compress to jpeg. 7. Assemble movie as .mov (format compatible with projection system in the dome). Does anyone have a better idea? I'm assuming that I can't change the camera to omnimax from within Chimera? Thanks for any suggestions! Kristina -- Kristina Furse Postdoctoral Research Associate 262 Stepan Chemistry Hall Notre Dame, IN 46556 (574)631-3904
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Hi Kristina, Wow, this movie sounds great!! Our main POV-Ray expert is not in today, but I can address one part of your question. It looks like postprocessing the *.pov files to specify "omnimax" is the way to go. Maybe it could be combined with the x3d2pov step somehow. Firstly, although you can change the viewing angle ("horizontal field of view," see Tools... Viewing Controls... Camera) in Chimera, I do not know if this setting is carried forward into *.x3d and *.pov output. Secondly, the POV-Ray documentation http://www.povray.org/documentation/view/3.6.1/247/ says that "omnimax" uses different amounts of fisheye distortion in the vertical and horizontal directions, which I don't think can be achieved in Chimera. I think adjusting the viewing angle in Chimera corresponds to changing the angle in perspective projection in POV-Ray. I would suggest validating your scripts with a smaller image size and without raytracing, but it sounds like you have already done that or something similar. If anybody else has thoughts or suggestions, please pipe up! Best, Elaine ----- Elaine C. Meng, Ph.D. meng@cgl.ucsf.edu UCSF Computer Graphics Lab and Babbitt Lab Department of Pharmaceutical Chemistry University of California, San Francisco http://www.cgl.ucsf.edu/home/meng/index.html On Feb 26, 2008, at 8:41 AM, Kristina Furse wrote:
Hi-
We're interested in using Chimera to prepare POVray files for a movie to be shown on a hemispherical dome. The first part of the movie will be a 360 degree rotation of a DNA/drug complex showing water occupancy around the drug, and the second half will come from an AMBER MD trajectory. We've figured out the content and rendering. The two remaining issues are that the camera must be changed from "perspective" to "omnimax" (fisheye), and the extensive rendering time that will be required for the large system at very high resolution (4096x4096). Here is our plan:
1. Use a command-line script to rotate the system and export the scene to x3d files. 2. Use per-frame scripting in MD movie to export each trajectory frame to x3d files. 3. Use x3d2pov to translate into *.pov files. 4. Change the camera from perspective to omnimax in each .pov file. 5. Render the individual images in parallel on our cluster using povray (different version than the one that ships with Chimera). 6. Compress to jpeg. 7. Assemble movie as .mov (format compatible with projection system in the dome).
Does anyone have a better idea? I'm assuming that I can't change the camera to omnimax from within Chimera?
Thanks for any suggestions! Kristina
-- Kristina Furse Postdoctoral Research Associate 262 Stepan Chemistry Hall Notre Dame, IN 46556 (574)631-3904
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Wow, this movie sounds great!!
Thanks! It started with the fairly innocent idea of making use of the digital imaging resources here to make something for recruiting that was based on real research and not canned fly throughs of buckyballs. (Not that a good buckyball fly through isn't fun...) It has snowballed in complexity as we have discovered the cool things you can do with Chimera.
Our main POV-Ray expert is not in today, but I can address one part of your question. It looks like postprocessing the *.pov files to specify "omnimax" is the way to go. Maybe it could be combined with the x3d2pov step somehow.
OK, good. That was the step we were least sure of.
Secondly, the POV-Ray documentation http://www.povray.org/documentation/view/3.6.1/247/ says that "omnimax" uses different amounts of fisheye distortion in the vertical and horizontal directions,
Yes--from our tests it looks very weird on a computer screen. Severe compression in the vertical but not the horizontal.
I would suggest validating your scripts with a smaller image size and without raytracing, but it sounds like you have already done that or something similar.
We are testing on a single frame to get the perspective -> omnimax conversion right. Looks like the camera needs to be moved significantly closer to the object, possibly with a change in viewing angle too. We're still working it out. We'll also test a frame on the dome before we swing into full production. Unfortunately, the guru who knows how to spit the image to the 8 projectors is out with the plague or something... Thank you! Kristina
On Feb 26, 2008, at 8:41 AM, Kristina Furse wrote:
Hi-
We're interested in using Chimera to prepare POVray files for a movie to be shown on a hemispherical dome. The first part of the movie will be a 360 degree rotation of a DNA/drug complex showing water occupancy around the drug, and the second half will come from an AMBER MD trajectory. We've figured out the content and rendering. The two remaining issues are that the camera must be changed from "perspective" to "omnimax" (fisheye), and the extensive rendering time that will be required for the large system at very high resolution (4096x4096). Here is our plan:
1. Use a command-line script to rotate the system and export the scene to x3d files. 2. Use per-frame scripting in MD movie to export each trajectory frame to x3d files. 3. Use x3d2pov to translate into *.pov files. 4. Change the camera from perspective to omnimax in each .pov file. 5. Render the individual images in parallel on our cluster using povray (different version than the one that ships with Chimera). 6. Compress to jpeg. 7. Assemble movie as .mov (format compatible with projection system in the dome).
Does anyone have a better idea? I'm assuming that I can't change the camera to omnimax from within Chimera?
Thanks for any suggestions! Kristina
-- Kristina Furse Postdoctoral Research Associate 262 Stepan Chemistry Hall Notre Dame, IN 46556 (574)631-3904
-- Kristina Furse Postdoctoral Research Associate 262 Stepan Chemistry Hall Notre Dame, IN 46556 (574)631-3904
participants (2)
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Elaine Meng
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Kristina Furse