Object invisible in reflections

[hrisek]

Bug in Corona 1.0 (not new bug fiex version). Path Tracing + HDCache is used. I wan to make my 3D Trees invisible for Camera but visible for reflections (trees should not cast shadows).
When i turn off "Receive Shadows", "Cast Shadows" and next i turn off "Visible in Camera" (object properteis) than my trees are invisible in reflections...when i turn on "Receive Shadows" and "Cast Shadows" than trees are visible in reflections...
What i'm doing wrong (or corona) ?

[romullus]

No need to use object properties for that. Turn everything back on, create CoronaRayswitch material, plug your tree material to rayswitch's Reflect override slot and assign that new material to your trees. That's it.

[hrisek]

but i have 5 leaves materials, 2 barks materials and 3 materials for branches...I have to create 10 new materials (rayswitch) ?

[hrisek]

And now i see that Your solution is not working for me...how can i make my tree INVISIBLE for camera, without shadows and visible for reflections with your trick (rayswitch)? Rayswitch can only which material is for reflective, refraction , GI and for camera...there is no option to "turn off" materials for shadows or "turn off" materials for camera...

[maru]

If you are using multi/sub object material, then no. We are talking about rayswitch material, not rayswitch map.
Maybe this will be helpful:
https://coronarenderer.freshdesk.com/support/solutions/articles/5000529341

[maru]

Is this what you want to achieve?

[hrisek]

Yes - this is what i want to make. Visible only in reflections without shadows....but sorry guys - i have 10 materials per tree and i have 6 species of trees....i have to change  60 materials???? it is joke? Why it's impossible to make it so easy like in Vray -  select all trees, turn off shadows casting, turn off visible for camera and voila...

[maru]

Hmmm... I don't know how your scene is made but here is the first thing I can think of:
-for each of the tree models, attach all parts of it to make it a single model
-pick material from it, it should be multi/sub material automatically
-then use the multi/sub material with rayswitch

If you have 6 species of trees, this would require only 6 materials.

[Frood]

No need to use object properties for that. [...]

"No need" is much more less effort than using rayswitch and is part of many workflows, including mine. A simple test with a mirrorball an a box (not even having a material) shows that when objects "Cast Shadows" setting is off the result is not what is to expect. The box looks somewhat transparent but the reflection does not completely disappear. I´m glad someone found this before I ran into that trap. This has to be fixed. Rayswitch is to be considered a a workaround here, not a solution imho.

Good luck!







 

[maru]

I know this is not a good excuse but as far as I know these settings are considered "fake" by Corona. And Corona doesn't like fakes. I am sure Ondra will take a look at this problem, though.

[Frood]

maru, I agree to the term "fake" but I don´t agree to break with absolutely basic max functionality. If this is considered NOT to work, object and layer rendering controls should be ignored COMPLETELY at the outset. And this should be clearly stated then. No one should be interested to turn Corona into a half-implemented renderer where features are not fully usable.

[PROH]

Hi. AFAIK the "invisible to camera" does work as inspected. But for shadows, reflections and reflections you need to use the Corona Rayswitch. Please correct me if I'm wrong.

I've searched the help files several times for some accurate explanation on which properties are supported and which not, without any luck. Would be nice to have a reliable help file about this.

Just for clearing up: Corona isn't the only renderer having problems with these properties. Iray as well - just for one - doesn't support all settings.

Would be nice to have a more efficient method to do these things than the Rayswitch anyway.

[Ondra]

This thread is too big of a mess, I am closing it down. If someone still has an unsolved problem, please try to describe it better in a new bug report (and with pictures ;)).

Frood: that looks like the expected behavior. Why should "cast shadows" disable entirely reflection? There is another checkbox for that. Casts shadows does exactly what it says - it disables shadows for the green box, so the environment is also visible on top of the object

[Frood]

Ondra, I never stated that it should. That (quoting myself sucks) "but the reflection does not completely disappear" in my post referred to the original post claiming a DIFFERENCE to what hrisek encountered. Also I wanted to point out that for this littlte test, only the shadow setting was used and all other object settings worked as expected and were not touched for this. Sorry if anybody misunderstood that.

[...] it disables shadows for the green box, so the environment is also visible on top of the object

Somebody pinch me please, I seem to have missed something? Why should there be environment visible through the box? Attached the same situation as mr rendering, that is what I would expect: The green box (object settings: Cast Shadows off) looks the same but it simply does not cast shadows. And the same as Corona rendering again, just to have the same angle/scene. Additionally the Corona scene again with some geometry around it. So this is expected behaviour?

Frood
*scratchinghishead*

[Ondra]

Yes, that is the expected behavior. Corona cannot behave the same as mental ray, as it uses 20 year old concepts, not 30 years old (multiple importance sampling). Also there are other situations where people protested the results they got - see attached - that is how it would look if "cast shadows" would mean something different.