How to make the floor invisible but keep the shadows?

Become a member of the CGSociety

Connect, Share, and Learn with our Large Growing CG Art Community. It's Free!

THREAD CLOSED
 
Thread Tools Search this Thread Display Modes
Old 07 July 2013   #16
Vray outputs a shadow pass that can be multiplied over your image background as well, so the workflow stays the same.
Now, if you are trying to render GI "shadows" this is not the same, since the "shadow" created here does not come from a light object, but from the lack of lighting bouncing around (much like real life).
For this, you're probably better off rendering your background directly in the scene, or fiddle with the various GI passes that Vray offers.
__________________
One on one Online Instructor for Cinema4D | Visit www.Fluffy4D.com for more info.
 
Old 07 July 2013   #17
OK, thanks

getting a bit off topic, but do you do all your multipass layers in vray for c4d? I've run across many posts where people say they only render beauty passes with it, then use the standard renderer for other passes
 
Old 07 July 2013   #18
Originally Posted by LML: OK, thanks

getting a bit off topic, but do you do all your multipass layers in vray for c4d? I've run across many posts where people say they only render beauty passes with it, then use the standard renderer for other passes


Your best source for all questions Vray:
http://forum.vrayforc4d.com/

Nothing better than getting your info "straight from the horses mouth"
__________________
The views expressed in this post are by no means the opinion of those making the post or of any one person in particular.
 
Old 07 July 2013   #19
If you want to do it straight out of Cinema in one image, here is a very strange yet effective approach. It works. I don't know why there isn't a more straightforward way to do a shadow catcher.

Shadow catcher
__________________
2014 Reel
Company website
Behance Portfolio
HyperactiveVR
I reject your reality and substitute my own
 
Old 07 July 2013   #20
Originally Posted by LML: OK, thanks

getting a bit off topic, but do you do all your multipass layers in vray for c4d? I've run across many posts where people say they only render beauty passes with it, then use the standard renderer for other passes

Most passes work fine in Vray, except for the object buffers (which are aliased) and I think vector motion blur.
The motion blur pass can be output in C4D. As for the buffers, the best is to use the MaterialID pass, or make them manually by using black and white materials which you place where needed.
The manual method is a bit of a hassle but works fine.

I personally use materialID passes.

As for the rest of the passes, they should work fine. You'll find that some passes are inverted compared to C4D (Depth pass - for which you need to invert the Depth parameters to work right - and shadow passes, for example), but you'll also find more passes available (raw passes, for example).
All in all, there are still some issues, but you should experiment and see if they fit your workflow.
__________________
One on one Online Instructor for Cinema4D | Visit www.Fluffy4D.com for more info.

Last edited by fluffouille : 07 July 2013 at 01:35 AM.
 
Old 07 July 2013   #21
ok, so, I'm lighting my scene with only an HDR map using the Phys renderer. Doesn't seem to be possible to catch the shadows made by the HDR map using anything. Any ideas how to catch a shadow for compositing using when only using HDR for lighting?
__________________
2014 Reel
Company website
Behance Portfolio
HyperactiveVR
I reject your reality and substitute my own
 
Old 07 July 2013   #22
You ll need to go the compositing route for this, because HDRI shadows are not actual 3D shadows (from a light object), but the result of illumination & GI (so, more a lack of light, than an added effect).

You could play with the Global Illumination pass and see if that suits your needs.
__________________
One on one Online Instructor for Cinema4D | Visit www.Fluffy4D.com for more info.
 
Old 08 August 2013   #23
Originally Posted by fluffouille: You ll need to go the compositing route for this, because HDRI shadows are not actual 3D shadows (from a light object), but the result of illumination & GI (so, more a lack of light, than an added effect).

You could play with the Global Illumination pass and see if that suits your needs.


That's what I figured. It would be great if you could at least drop a light into your scene and be able to turn off illumination while still being able to create a shadow. I would think that would at least be possible. Multipass is all new to me, I traditionally like to try and nail everything in one pass, but I'm trying to step outside my comfort zone and learn some new techniques.

So creating a GI pass includes the shadows it creates or what exactly is created?

Also, I would have thought that something like an AO pass would create something like all of the AO noise against transparent or coupled with some sort of Alpha map. Would be extremely useful if you're trying to create an object with it's shadow against transparent. Trying to create several stills that a compositor can just drop into Final Cut, no AE involved.
__________________
2014 Reel
Company website
Behance Portfolio
HyperactiveVR
I reject your reality and substitute my own
 
Old 08 August 2013   #24
It would be great if you could at least drop a light into your scene and be able to turn off illumination while still being able to create a shadow.


Light panel / Detail Tab / Checkbox Shadow Caster = No illumination but still shadows.

Edit : black and white shadow/GI or AO passes can be used in any pro NLE by setting them to multiply or screen in the timeline. No need for AE there. If certainly works in Premiere.

Best,
Eric
 
Old 08 August 2013   #25
Originally Posted by EricM: Light panel / Detail Tab / Checkbox Shadow Caster = No illumination but still shadows.

Edit : black and white shadow/GI or AO passes can be used in any pro NLE by setting them to multiply or screen in the timeline. No need for AE there. If certainly works in Premiere.

Best,
Eric


I would assume FCP can do this as it's a pretty basic feature, but I don't want to provide a multilayer file and one issue is the model is mostly white as well as the background and floor. Hence the issue.
__________________
2014 Reel
Company website
Behance Portfolio
HyperactiveVR
I reject your reality and substitute my own
 
Old 08 August 2013   #26
Originally Posted by EricM: Light panel / Detail Tab / Checkbox Shadow Caster = No illumination but still shadows.


Did not know it could do that. Thanks!
__________________
2014 Reel
Company website
Behance Portfolio
HyperactiveVR
I reject your reality and substitute my own
 
Old 08 August 2013   #27
All you need is a shadow catching shader in alpha or trans and your done.
 
Old 08 August 2013   #28
Thread automatically closed

This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.
 
Thread Closed share thread



Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
CGSociety
Society of Digital Artists
www.cgsociety.org

Powered by vBulletin
Copyright ©2000 - 2006,
Jelsoft Enterprises Ltd.
Minimize Ads
Forum Jump
Miscellaneous

All times are GMT. The time now is 11:23 AM.


Powered by vBulletin
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.