Hi Katie- > Thanks so much for getting back to me and for trying out my files on > your system. Unfortunately, my network won't allow me to receive > graphical attatchments (don't ask me why) so could you resend the > attatchment either to my personal email or > to this address but as part of a Word document? Thanks so much for all > your help and patience. I've cc'd your other email on this response with the attached image. BTW, I fixed the problem with the display only showing up as a thin column. It was a problem with the projection as I suspected. I now make sure we are in the correct projection before calculating the volume for rendering. The fix is in the latest nightly build. I also noted that your lat/lon points in the netcdf file don't match up with shape of the topography image. The topography image looks like southern Florida (except upside down and backwards), but the lat/lon points put it in a smaller area, just east of Key West (lats from 24.3762 to 24.82356, lons from -81.6238 to -81.17645). It looks like it should go from about 24 to 27 and from -82 to -79 from the topography. Maybe this was just meant to be a sample, but just wanted you to know in case it's not. Don > -----Original Message----- > From: Unidata IDV Support [mailto:address@hidden] > Sent: Wednesday, April 23, 2008 5:47 PM > To: Carbonari, Katie > Cc: address@hidden > Subject: [IDV #WNR-458825]: Problem w/volume rendering > > Hi Katie- > > > Thanks so much for your quick response. > > This one took a little longer. ;-) > > > We have been using the 64 bit version of Java, but we get the same > problems when we run the 32 bit version (of course, we have to use a > smaller data set of 250x250x50). If it's not too much trouble, could you > try to render our data set on your setup? We're using a new machine (a > Mac) and want to be sure that the problem is not with the way ours is > configured. If you could do a volume rendering of the data (lwc) and > send us a screen shot, we'd be very much appreciative. If you're > successful, please let us know what you're using (os, graphics card). > Enclosed is a screen shot of the same data in VAPOR. While VAPOR lacks a > lot of the functions we need (that IDV has), it is giving excellent > results in the volume rendering. Our goal is to get our clouds in IDV to > look as good as the clouds in VAPOR. > > I'm not sure you'll get as good as VAPOR, but I've attached a screen > shot of what I was able to produce. It took a long time because we do > on the fly what VAPOR does when it transforms your netCDF file initially > - put the data into display coordinate space. We do it on the fly > because you can display the data in any projection you want. > > I also ran into the issue with it sometimes producing just a small > column. I think that's an issue with the projection changing when you > display the data. If you set the projection to the data space first > (e.g. display a plan view of qc or something), then I don't think that > will be an issue. I'll look into that more closely when I get a chance. > > My graphics card is an ATI Mobility Radeon X1400 w/ 512 Mb. I am using > the Texture3D. Turning that off made a less pretty display. > For the attached, I set the data range to be 150 to 247 and > I set the transparency to be 50%. The other person who > had the problem with the Texture3D was also using a Mac. He had a > NVIDIA GeForce 8600M GT with 256 Mb RAM. > > Don > > -----Original Message----- > > From: Unidata IDV Support [mailto:address@hidden] > > Sent: Fri 4/18/2008 3:36 PM > > To: Carbonari, Katie > > Cc: address@hidden > > Subject: [IDV #WNR-458825]: Problem w/volume rendering > > > > Hi Katie- > > > > > Hi Don. I have a few more questions concerning volume rendering I > hope you can help me with. > > > > > > First off, a little background. I'm trying to do volume rendering of > lwc (liquid water content, clouds) over terrain. Each file is a netCDF > file (80 meg) that has 1250x1250x50 points of liquid water plus > 1250x1250 of terrain elevation. There are 60 files total to be > visualized (1 file=1min). There are several problems I've been having: > > > > > > 1) Even with 12 gig of memory allocated to IDV, often volume > rendering runs out of memory, even at much courser resolutions. Are > there any parameters I can change that will speed up the volume > rendering? > > > > Does the memory monitor actually show 12 Gb allocated? Are you > > running a 64 bit version of Java? The 32 bit version will only > allocate 2 Gb. > > > > > 2) Sometimes IDV does not use the full 12 gigs allocated to it, but > still takes a very long time to render. Is this just because my data set > is so large? > > > > Volume rendering is very much a hog of memory. To do the volume > > rendering we have to retransform the entire dataset. If these are > > staggered WRF grids, that will be even worse because we need to > destagger them. > > > > > 3) Occasionally, instead of getting the entire volume rendered, only > > > > a small "chimney" will be visualized. It appears to be the full data > > > > set but only over 1/20 of the proper area. Any ideas about what > > > causes this? (Of course, I can't get it to do it now, so I don't > > > have a screen shot to show you) > > > > I hate problems like that. ;-) I can't think of anything off the top > > of my head that would cause that. > > > > > 4) Once the data is fully loaded, I can't seem to make the clouds > > > look like clouds. I want to control the volume to be colored by > > > opacity, not color. If the lwc is below a certain threshold value, I > > > > want those points to be totally transparent (ie, want to be able to > > > see straight to the ground). Any advice on how to control the > > > opacity in this way? (see attached photo of how our clouds currently > > > > look; they are not very good-looking clouds) > > > > The image didn't come across, but here are a couple of suggestions. > > First, use the Visible Range in the display control to set the range > > of the values you want to visualize. Alternatively (or in addition > > to), edit the color table and set the transparency for the range you > > don't want to see to 100% and the values you want to see to 90%. That > > > will make those values you want to see more "cloudy". Transparency is > > > order dependent, so if you have other displays in the View, you'll > > want to use the View->Bring to Front menu on the Volume Control so you > can see the other displays. > > > > > Thank you so much for your time, > > > > Don > > > -----Original Message----- > > > From: Unidata IDV Support [mailto:address@hidden] > > > Sent: Thu 4/17/2008 5:34 PM > > > To: Carbonari, Katie > > > Cc: address@hidden > > > Subject: [IDV #WNR-458825]: Problem w/volume rendering > > > > > > Hi Katie- > > > > > > > Full Name: katie carbonari > > > > Email Address: address@hidden > > > > Organization: northrop grumman > > > > Package Version: 2.5 > > > > Operating System: linux > > > > Hardware: > > > > Description of problem: Hello. I've been trying to do some volume > rendering of clouds in IDV. Isosurface works fine (as you can see in the > attatched picture) but volume rendering gives a gray cube. This gray > cube doesn't change when I change various parameters (color range, > transparency, etc). Any ideas on why this is happening? The 2 pics are > of the same data file, so I don't know why the volume rendering doesn't > give clouds. > > > > > > This is probably a graphics card issue. What is the graphics card > > > you are using? > > > > > > Try the following: > > > > > > - do the volume rendering > > > - bring up the properties for the Volume Rendering control > > > (Edit->Properties menu of the control). > > > - Uncheck the Use Texture 3D property and click the OK button. > > > > > > Does that make your volume rendering appear? > > > > > > Don Murray > > > > > > Ticket Details > > > =================== > > > Ticket ID: WNR-458825 > > > Department: Support IDV > > > Priority: Normal > > > Status: Open > > > > > > > > > > > > > > > > > > > > > > > > Ticket Details > > =================== > > Ticket ID: WNR-458825 > > Department: Support IDV > > Priority: Normal > > Status: Open > > > > > > > > > > > > > Ticket Details > =================== > Ticket ID: WNR-458825 > Department: Support IDV > Priority: Normal > Status: Open > > Ticket Details =================== Ticket ID: WNR-458825 Department: Support IDV Priority: Normal Status: Open
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