Forest Pack objects with opacity mapping "leaking" through foreground objects

[The Pixel Artist]

Been seeing this issue on a few scenes that have Forest Pack scattered tree/plant objects.  The FP objects are "leaking" though other foreground objects.  Finally isolated the issue down and found that it was only the scatter objects that used opacity masks in the materials.

Below are a few images to hopefully demonstrate better.
Also, here a panoramic image I rendered that shows the problem as well.
http://www.thepixelartist.com/images/corona/20140126_opacity_bugs/index.html


This has been an issue for at least the last three builds (1/16, 1/17, 1/24), haven't tested it with V5 though.


I'll also mention that I've seen another issue where some forest pack objects will not render at all, even though it's visible (and on) in the viewpoint.  It seems to be intermittent, as after starting the render again that FP object might now render fine, but other FP object might not.  I've been trying to duplicated the issue without luck and may have been fixed in the 1/24, as I havent' noticed it yet.

[Ondra]

Can you upload me the scene? (http://corona-renderer.com/upload/)

[The Pixel Artist]

Sure, but it'll have to be another scene, as this one has a GB or two in resources (plus it's still a propitiatory scene).  I'll make a custom scene with less object to send in just a little bit.

[Ondra]

ok, anything where you can reproduce it, the smaller the better.

[The Pixel Artist]

I just tried building a small test scene and imported that exact same mesh and FP object.  But couldn't reproduce it in the new scene. (see attached image)

However, I've seen this issue now in 3-4 scenes, all quite large scenes with lots of geometry/texture/xrefs/etc, that also started off as Vray scene, then converted to Corona.  So this could be a tricky one as the problem could be do to scene scale, conflict with other mats or FP objects, etc.  Some of the problem plants are also xref'd, but I ruled that out already (did a test were I merged everything).   Could be a conversion issue or bad mat, but I've gone though all the tree mats to make sure they were OK.  Only factor I found was the opacity maps.

I'm going to PM you a dropbox link to another scene that was showing some of the same problem, plus another big Forest Pack issue that I'm about to make another post about.  (random disappearing FP objects).

[Ondra]

note to self: 20140126.zip

[mirokurcik]

This is not a problem ForestPack, I got the same result with CoronaScatter.
The reason is transparency material (leaves with alpha channels), but the solution I have not found yet.

[mirokurcik]

examples:

[Ondra]

ok, I think I know what is causing this. Will attempt to fix later

[The Pixel Artist]

Cool, that's very good news.  Best of luck and thank you!

[The Pixel Artist]

ok, I think I know what is causing this. Will attempt to fix later

Keymaster, any luck with this problem?  It's really driving me crazy, because all of my good trees/plants use opacity mapped leaves and will cause this problem with FFP or CoronaScatter.

[Ondra]

probably fixed. I cannot verify it in the scene since I dont have VRay and you are using vray cameras.

[The Pixel Artist]

That's terrific to hear, thanks KM!!

I'll make sure to test it out.  Is this already fixed in the 2014-02-05 build or the next one?

[Ondra]

it will be in the next one

[The Pixel Artist]

I'm happy to confirm that as of the 2014-02-06 update it does appear to be fixed based on my first tests!  Awesome!!!!  Thanks again!