jjstanley Posted July 1, 2005 Share Posted July 1, 2005 I am trying to use the SSSfull5 and not sure were to put everything. I have the otl's loaded but what about the items in the other folders? Thanks, I can't wait to try it out! Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 1, 2005 Share Posted July 1, 2005 I have that all figured out and working quite well. I am very impressed and having a lot of fun with it. I was wondering though how to set it up in VOPS to vary the "density" of the object. I am trying to set up ice and want to have the strata compressions in ice. I have tried lots of thing in VOPs but not getting anything that looks right. I am guessing that either a Turbulent Noise or Ramp should work but should I put them before or after the SSS VOP? The best result I have had so far is Ramp into the ksss on the SSS but still not quite right. THanks for any ideas. Quote Link to comment Share on other sites More sharing options...
Mario Marengo Posted July 3, 2005 Author Share Posted July 3, 2005 I am trying to set up ice and want to have the strata compressions in ice. Hi jjstanley Basically, there are two ways of doing this, one is cheap and the other expensive. The cheap way is to assume the material has the same scattering characteristics everywhere (homogeneous) and then modulate the overall result with some texture map or something. It probably won't look as good as the expensive way, but if you can get away with it, I'd say go for it. And the expensive way is to evaluate the actual scattering using either a varying scattering distance or a varying surface color, but for a varying surface color you need to toggle "Evaluate RGB Separately" on. If you choose the expensive way, here's the key thing to remember: the less distance the light scatters, the more points you'll need in your cloud. So if the minimum scattering distance given in your variations is way smaller than the distance between points in your cloud, then there won't be enough points to filter and the image will probably end up looking screaming white... increase the number of points in your cloud until the average distance between them is about 1/4th the minimum expected scattering distance. This is not an issue for single scattering if you choose to do single scattering using ray tracing (omit entering a point cloud map). Here's the demo hip file with some horizontal bands of varying density (you'll have to generate the cloud before rendering): test_thindisk2.zip Hope that helps, Cheers! Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 4, 2005 Share Posted July 4, 2005 That looks awesome! I have followed trough the file and I think I can make sense of all of it. There a few spots I will need to play with a bit to understand exactly how they affect the final render. The main problem I am having is outputting a point cloud file. I have made sure that the folder is there, tried other folders, and reopened the file but the .tbf is never created. On the other thin-disk file I did not have any problems so I know that it has worked on my computer. Is there a way to freeze the command screen so I can see what is happening? It just blips on the screen so fast I can't read any of it. I'm sure there is some very simple thing I am missing but I am running out of things to try. Quote Link to comment Share on other sites More sharing options...
Mario Marengo Posted July 4, 2005 Author Share Posted July 4, 2005 On the other thin-disk file I did not have any problems so I know that it has worked on my computer. Is there a way to freeze the command screen so I can see what is happening? It just blips on the screen so fast I can't read any of it. I'm sure there is some very simple thing I am missing but I am running out of things to try. Try moving the new test_thindisk2.hip file to the same location as your old test_thindisk.hip file that came with the SSSfull5 bundle. Open it there and save the point cloud... it should do it without complaining. It tries to save to $HIP/Map, where $HIP is the directory where the hip file itself lives. And if the subdirectory Map doesn't exist, then it won't save. I'm guessing that's what was happening. Cheers! Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 6, 2005 Share Posted July 6, 2005 I have no idea what is going on but it just will not output a .tbf file for me. Does it need the "opname" param in the name? Is there a way to see what is happing from the command window? It goes so fast I can't read it. I have tried changing directories and gone over file names and locations until I think I must be going crazy! A whole search on the hard drive only turns up the original .tbf file that is in the original ZIP file. Any other ideas would be great. Sorry to be such a pain. Jerry Try moving the new test_thindisk2.hip file to the same location as your old test_thindisk.hip file that came with the SSSfull5 bundle. Open it there and save the point cloud... it should do it without complaining.It tries to save to $HIP/Map, where $HIP is the directory where the hip file itself lives. And if the subdirectory Map doesn't exist, then it won't save. I'm guessing that's what was happening. Cheers! 19235[/snapback] Quote Link to comment Share on other sites More sharing options...
edward Posted July 6, 2005 Share Posted July 6, 2005 I don't remember now but H7 might not have had support for writing out .tbf files yet. Quote Link to comment Share on other sites More sharing options...
Mario Marengo Posted July 6, 2005 Author Share Posted July 6, 2005 Strange... No, H7 doesn't save .tbf files but that's why I put a little script in the HDA that would save .bgeo and then run i3dconvert on it to turn it into a .tbf. Are you on Windows? Could it be that your environment is not set up correctly? When you run i3dconvert in a shell, does it spew out a help message, or do you get a "command not found" error? If all else fails, then go inside the HDA "Multi", RMB on the yellow-colored nullSOP called "PCLOUD" and select "Save Geometry...", then save as .bgeo to some location where you have permissions. then change the "Pointcloud File" parameter in the shader to point to this .bgeo file you just saved. It *should* work (either .bgeo or .tbf files should work, but .tbf files are more memory efficient). Let me know if that works. Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 6, 2005 Share Posted July 6, 2005 I am trying to use the i3dconvert command line but I get the error "No attribute data was found on geometry file." What does that mean? I think I am very close but just missing something. I am also curoius about the SH_disp shader. I have been trying it on different objects and on some it works great and others the object seem to break apart. Why would that be? Thanks for all the help! Quote Link to comment Share on other sites More sharing options...
Mario Marengo Posted July 7, 2005 Author Share Posted July 7, 2005 I am trying to use the i3dconvert command line but I get the error "No attribute data was found on geometry file." What does that mean? I think I am very close but just missing something. Not sure what that error is about, but you should run i3dconvert like this: i3dconvert -c input.bgeo output.tbf But remember that you can still just use .bgeo files and forget this whole .tbf headache if it's not working for you. I am also curoius about the SH_disp shader. I have been trying it on different objects and on some it works great and others the object seem to break apart. Why would that be? 19333[/snapback] Hmmm... that's just a plain-vanilla noise displacement shader -- nothing fancy going on there. Perhaps you're feeding it polys with unique'd points (i.e not fused)? In any case, please feel free to use your own displacement shader. That was just a quick example of how to duplicate displacement for both the pointcloud and the shaded surface, but displacement is not at all required to get subsurface scattering to work. Cheers! Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 8, 2005 Share Posted July 8, 2005 The displacement shader issue is actually one that has plagued me in Houdini. It is not just yours. If I take a grid and apply a surface and displacement shader such as VEX_choppywater, as soon as the camera is brought down to a low angle the water appears to break apart. Changing the size of the grid seems to have little to no effect and I have tried every SOP I can think of including the Fuse and nothing seems to help. It is one of the few consistant problems I have had with rendering in Houdini and have not seen this happen in any other 3D apps so not sure what I am doing wrong. I have the SSS shader working nicely although i'm sure slower than it should as the bgeo is quite large and I have to keep high detail to make the scatter work right. I will post some pics soon. Quote Link to comment Share on other sites More sharing options...
edward Posted July 8, 2005 Share Posted July 8, 2005 Did you increase the displacement bound? Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 8, 2005 Share Posted July 8, 2005 I am not sure what htis is or how to change it. I lookes in several shops and could not find any settings for it. How would I do this? Did you increase the displacement bound? 19364[/snapback] Quote Link to comment Share on other sites More sharing options...
sibarrick Posted July 8, 2005 Share Posted July 8, 2005 It's on the render tab of the parameters at object level for each object you can set it individually. Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 8, 2005 Share Posted July 8, 2005 Thanks, I'll give that a try. Here is a test render I just did. It's on the render tab of the parameters at object level for each object you can set it individually. 19370[/snapback] Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 8, 2005 Share Posted July 8, 2005 Here is one with some transparency. My next step is to get a slightly melting feel to it. Thanks, I'll give that a try. Here is a test render I just did. 19372[/snapback] Quote Link to comment Share on other sites More sharing options...
jjstanley Posted July 11, 2005 Share Posted July 11, 2005 Thanks for the tip on the displacement bounds. It does help in most setups. I'm really strating to understand VOPs better and it's a lot of fun. Thanks everyone for the help. Quote Link to comment Share on other sites More sharing options...
abvfx Posted May 3, 2006 Share Posted May 3, 2006 on the subject of vops, i cant get my file to work. I got the demo working, which means i have the vops and the sample shader. But when i use it on my characters i get a black render. I have recreated the demo file and still cant get it woring and i know why. My inability to use Vop's correctly. Could someone show me how to setup my vop shop network as all im doing is getting a ayzx single and pluging the output to the colour or the output vop. I have no parameters etc because of the way i just tried to plugin and play. Do i need the specular vop, or a lighting model? please help, cheers Quote Link to comment Share on other sites More sharing options...
symek Posted May 3, 2006 Share Posted May 3, 2006 Did you render out pointclouds first and point shader to your file on disk? Sorry, but this is first thing has came to my mind... basics. If you done this, you should write something more or send your hip file. cheers, SY. Quote Link to comment Share on other sites More sharing options...
abvfx Posted May 3, 2006 Share Posted May 3, 2006 yea i did the whole point cloud setup, shoulda added that in my post... doh! I will construct a quick scene, and should it not work and i feel everything is in its rightful place i will post here and await that vital and simple step that i carelessly missed hehe. Thanks for your response Symek, thought this thread might be a ghost town . Quote Link to comment Share on other sites More sharing options...
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