Volumetric lights and transmap Issues
Zev0
Posts: 7,045
Is it possible to get volumetric lights to shine through transmapped areas and actually working? Eg I have a tree and transmapped leaves but when I apply a volumetric light all the transmap planes are visible and I have a tree with all these squares and my god rays cast shadows around those. Is there a solution to this?
Post edited by Zev0 on
Daz 3D is part of 
Connect
DAZ Productions, Inc.
224 S 200 W, Suite #250
Salt Lake City, UT 84101
Licensing Agreement | Terms of Service | Privacy Policy | EULA
© 2024 Daz Productions Inc. All Rights Reserved.
Comments
I dont know about a fix in 3delight, but transmaps with fog does work when using Reality 2.0
To me, Fog and Volumetric are two different things. Fog works fine with transmap in DAZ Studio. Its volumetric vs transmap that is the issue. Volumetric creates the effect below. I can get this with a full polygon tree with polygon leaves but not transmapped leaves. To be specific I am using this
http://www.daz3d.com/shop/atmospheric-effects-cameras-for-daz-studio/
I don't do much with volumetric lighting, but if you're seeing a consistently reproducible issue then please file a bug report on it. That's the best route to getting it fixed. Thanks!
Thats the thing. Is it a bug Or just a software limitation? Or is there a setting I am overlooking? I don't want to file a bug report unless it definately is one.
What's your raytrace depth set to? Remember for transparency it has to be [layers of transparency] +1 for any type of shadow/special effect to work.
Where is that setting? Oh found it. Mine is set on 2
Doubtful that is high enough. That would be only a single transmapped leaf of thickness. I'm wondering if it's even possible to set it high enough to work. LOL. The old default used to be 6, you might try that, but even that assumes that there's no point where you will have more than 5 leaves in a row before you get to the ground...
I'll bump it up and do a test render and see what happens..
Be prepared for a massive render time hit. ^_^
OK did my test render and its the same story. Bumped the Ray trace depth up to 10. I used this tree because it is a combination of polygon and transmap. The top part is polygon, hense no issues. On the trunk is transmapped areas. Notice the white transmap blocks.
I'd say a bug report is in order.
OK. I'll submit one. Thanks
Hi Zev0,
Thanks for reporting the bug. This is something that I and the testers missed before releasing the cameras. We did test with transparency but, evidently, the situations we tested under didn't produce the flaw or the error was so faint we didn't notice it.
At this stage I think I know what the issue is but I haven't yet figured out how to correct it. I am able to lessen the problem in some cases by changing the start distance to 0 and increasing the end distance (You may need to increase the limits of the slider to allow this). This does not eliminate the problem and may not even lessen it in all cases but it may be worth a try.
Please forgive me for not noticing it pre-release and for not having a proper fix yet. I will continue to work on the camera to see if I can't find a solution then update it.
Sorry about the problems,
William
Was this problem ever resolved with an update?
Not that I know of. I still use it a lot though, just now when I use the volume camera I use less transmapped objects. Its also dependant on what lights you have in the scene. Sometimes its not so bad, but still an isue.
No, there has not been an update though the issue has not been forgotten. The cameras do work in DS 4.5 but the issue with the volumetric camera showing transparent objects slightly darker or lighter than they should be is still there. It is a very puzzling issue and, so far, I have not found a solution.
The only thing I can recommend at this point is to set the Distance Start setting in the Volume camera to 0 and increase the quality as it lessens the inconsistency. You can virtually eliminate the transparency problem by adjusting those 2 settings.
Honestly, the fact that the quality setting affects the strength of the volume inside transparencies proves to me something is not working quite right. Unfortunately the code to correct it has eluded me so far.
Here are two possible ways to lessen the issue.
Solution 1: Set the Volume Distance Start at 0 and the quality to 99%
Solution 2: With lower quality settings, turn off the limits on the Distance Start Parameter and set it to a value slightly less than 1. In my tests a Distance Start setting of -0.25 Meters worked the best when the quality setting was at 50%. A Distance Start at -0.42 gave the best results when the quality setting was at 10%.
The lower the Distance Start setting the brighter the fog inside transparent objects became. So if you are using a low quality setting and your transmapped objects are too dark then try setting the start distance to a small negative value. If they are too bright then try increasing the start distance a little bit.
Solution 1 gives the best results but does take longer to render. I'll post some examples from my tests.
But the effect is different with a transparent obj compared to a transmapped obj. With transmapped the obj is at full opacity but is masked out by a transparency texture, which is where the problem lies isn't it? I'll do more testing on my side. As stated before this is a fantastic product and I hope something can be done.:)
....yes been running into a similar issue.
For example the JeanZ for V4 use transmaps for the shorter legging styles. In the pic below I applied the "short shorts" style and you can still see an outline of the full length legging transmap. Shortening the leggings by turning off the shin and thigh zones doesn't work as it doesn't give a smooth clean edge.
Ye. Its even worse when the light is coming from behind towards you.
Sorry for not replying yesterday... It was a busy day.
I did do additional tests with transparency maps and my results were the same where setting the Distance Start to 0 and the quality high eliminated the problem with transparency. Also using the second method of setting the Distance start to slightly lower than 1 when using lower quality settings helped lessen the issue too. All these tests were done in DS 4.5.
Just to be sure I did a few with a bright light behind the transmapped objects with and without shadows. Here are some examples of the high quality tests.
WOW. Thanks for looking into this. I will use these settings. Those example are perfect for what I need.
What is the settings for the fog density, light density in your last 3 examples? Also what brightness is that light set on?