g17 Posted December 6, 2023 Share Posted December 6, 2023 Hi, I'm trying use my explosion VDB (density,scatter,temperature,vel) as a holdout using the render geometry settings and it doesn't seem to work, as I'm still able to see my explosion. Is there any other setting that I need to be aware of for this to work. pls let me know. Thanks, Ganesh Quote Link to comment Share on other sites More sharing options...
fencer Posted December 6, 2023 Share Posted December 6, 2023 rendergeometrysettings Primitives > /object_path/ Shading > Holdout mode > Matte Quote Link to comment Share on other sites More sharing options...
g17 Posted December 6, 2023 Author Share Posted December 6, 2023 (edited) 11 minutes ago, fencer said: rendergeometrysettings Primitives > /object_path/ Shading > Holdout mode > Matte Thanks..I have done that already. But for some reason its not not working when i set to matte but it does work when i set it to phantom as phantom Edited December 6, 2023 by g17 Quote Link to comment Share on other sites More sharing options...
fencer Posted December 7, 2023 Share Posted December 7, 2023 Are you sure you're getting what expect? Matte is masking by object (will be empty space instead of object), Phantom keep object behind and add shadows from phantom object. Quote Link to comment Share on other sites More sharing options...
g17 Posted December 7, 2023 Author Share Posted December 7, 2023 (edited) 27 minutes ago, fencer said: Are you sure you're getting what expect? Matte is masking by object (will be empty space instead of object), Phantom keep object behind and add shadows from phantom object. So ..to be clear .when i set it to matte I'm still seeing my explosion instead of empty space which is the issue I'm facing .and when i set it to phantom.. the explosion is not visible in primary ray but visible in seondaries .. which is working as expected Edited December 7, 2023 by g17 Quote Link to comment Share on other sites More sharing options...
fencer Posted December 7, 2023 Share Posted December 7, 2023 (edited) I guess you see is emission in the matte mode. Edited December 7, 2023 by fencer Quote Link to comment Share on other sites More sharing options...
g17 Posted December 7, 2023 Author Share Posted December 7, 2023 1 hour ago, fencer said: I guess you see is emission in the matte mode. Thanks Paul..but unfortunately i see the explosion in alpha as well Quote Link to comment Share on other sites More sharing options...
g17 Posted December 7, 2023 Author Share Posted December 7, 2023 so it seems like the matte is working after disabling the material assignment on the actual explosion.. Quote Link to comment Share on other sites More sharing options...
fencer Posted December 7, 2023 Share Posted December 7, 2023 (edited) In this case you will lose correct density masking. Simply turn off Scatter/Fire in the shader. There is an easy trick as well, you can duplicate explosion and use first for matte, second for light. matte_volume_XPU_v01.hip Edited December 7, 2023 by fencer 1 Quote Link to comment Share on other sites More sharing options...
g17 Posted December 7, 2023 Author Share Posted December 7, 2023 Thanks for the file Paul Really appreciate it .I totally agree with u as i am loosing the correct density masking. i did try disabling fire and scatter..it didn't do any good. But i will look into your file. and also duplicating the pyro and using one for matte and one for phantom is a great idea... thanks you again. Cheers, Ganesh 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.