ddintz Posted August 18, 2010 Share Posted August 18, 2010 i am trying to have smoke emit from just a painted red($CR) area of an surface. similar to what you can do in pops. right now i think i have a convoluted process, in pops i got particles emitting on just the red area, and then i emitting smoke from those points. is there a better way? i rather not use points if i dont have to. thanks! d Quote Link to comment Share on other sites More sharing options...
Macha Posted August 18, 2010 Share Posted August 18, 2010 How about you delete the non-red points? Or do you want emission to be based on the color's strength as well? Quote Link to comment Share on other sites More sharing options...
ddintz Posted August 18, 2010 Author Share Posted August 18, 2010 yeah, in pops, i have birth probability at $CR and $CR. Source is set to emission type 'surfaces random' and that works well... justs births on the red, and the intensity of red will determine the amount birth. good technique. but i'd rather not use pops with the smoke fluids... curious to see if there is something comparable in volume fluids, emit just from the surface $CR. cheers, d How about you delete the non-red points? Or do you want emission to be based on the color's strength as well? Quote Link to comment Share on other sites More sharing options...
johner Posted August 18, 2010 Share Posted August 18, 2010 yeah, in pops, i have birth probability at $CR and $CR. Source is set to emission type 'surfaces random' and that works well... justs births on the red, and the intensity of red will determine the amount birth. good technique. but i'd rather not use pops with the smoke fluids... curious to see if there is something comparable in volume fluids, emit just from the surface $CR. If you're using the ApplySource DOP to do the emission, it supports multiplying the emission amount by a point attribute value. See the attached file. Coincidentally, I just posted a more complicated file that uses that feature here. emit_density_painted.hip Quote Link to comment Share on other sites More sharing options...
Macha Posted August 18, 2010 Share Posted August 18, 2010 I think this works. emi.hipnc Quote Link to comment Share on other sites More sharing options...
Macha Posted August 18, 2010 Share Posted August 18, 2010 Uups, sorry Johner, didn't see your post. Same method though. Quote Link to comment Share on other sites More sharing options...
ddintz Posted August 18, 2010 Author Share Posted August 18, 2010 great, thanks guys. yeah, thats it. I think this works. Quote Link to comment Share on other sites More sharing options...
Jim M Posted August 19, 2010 Share Posted August 19, 2010 (edited) Your example doesnt work for me Macha, as the whole thing emits. Also Johners example doesnt work right for me either, I see what it should do, yet it still emits from the whole object, not just the red painted bit. I am having a few issues with the install after deleting a shelf, that wont come back. I think I need to reinstall. Will see if that helps, as its been really buggy since i did that. Edited August 19, 2010 by Jim M Quote Link to comment Share on other sites More sharing options...
Macha Posted August 19, 2010 Share Posted August 19, 2010 (edited) Your example doesnt work for me Macha, as the whole thing emits. Also Johners example doesnt work right for me either, I see what it should do, yet it still emits from the whole object, not just the red painted bit. I think what you are seeing is a mixture of noise, fluid behavior and emission from points with $CR not exactly 0. If you remove all those factors you can see that there is no emission. It may be that if you try and render the whole thing with a pyro shader you don't see certain parts that you see in the viewport as there are remappings applied to the smoke density and other fields. I guess this is much simpler in the viewport, although I haven't tried it in this particular example. Edited August 19, 2010 by Macha Quote Link to comment Share on other sites More sharing options...
Jim M Posted August 19, 2010 Share Posted August 19, 2010 I think what you are seeing is a mixture of noise, fluid behavior and emission from points with $CR not exactly 0. If you remove all those factors you can see that there is no emission. It may be that if you try and render the whole thing with a pyro shader you don't see certain parts that you see in the viewport as there are remappings applied to the smoke density and other fields. I guess this is much simpler in the viewport, although I haven't tried it in this particular example. I reinstalled and both example work as expected. Ta! Quote Link to comment Share on other sites More sharing options...
ddintz Posted August 19, 2010 Author Share Posted August 19, 2010 hi Jim, in the apply_source > SDF Generation> turn on 'Copy DFS Volume from Source Object'. its not turned on by default. also, like in my case i am animating the color across, check on 'Use Deforming Geometry' below that. Your example doesnt work for me Macha, as the whole thing emits. Also Johners example doesnt work right for me either, I see what it should do, yet it still emits from the whole object, not just the red painted bit. I am having a few issues with the install after deleting a shelf, that wont come back. I think I need to reinstall. Will see if that helps, as its been really buggy since i did that. Quote Link to comment Share on other sites More sharing options...
Jim M Posted August 19, 2010 Share Posted August 19, 2010 hi Jim, in the apply_source > SDF Generation> turn on 'Copy DFS Volume from Source Object'. its not turned on by default. also, like in my case i am animating the color across, check on 'Use Deforming Geometry' below that. Thanks m8. It was an install problem. Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.