KeyShot Forum

Technical discussions => General discussion => Topic started by: Paleohunter on August 04, 2017, 10:54:22 AM

Title: Backface Culling?
Post by: Paleohunter on August 04, 2017, 10:54:22 AM
Hi all,

I have ran into an issue that I'm hoping that you can help me with. I need to not render the backfaces that are facing the camera in this scene. This is a Lidar scan of a cave and I need to exclude the roof of the cave for this render. I found an older post that suggested adding an emissive node in the material graph, I tried that but it didn't work for me.

Keyshot 6.3 Pro for Zbrush is the version I'm using.

Thanks!
Title: Re: Backface Culling?
Post by: DriesV on August 04, 2017, 12:27:52 PM
If you enable Experimental features (Preferences > Advanced), then you get the Surface Backside Mask utility node in the Material Graph. You can hook this up to the Opacity channel, with maybe a Color Invert in between depending on the normal orientation. This will give you the desired effect.

Dries
Title: Re: Backface Culling?
Post by: DriesV on August 04, 2017, 12:30:40 PM
Something like this rather simplified cave. :)

Dries
Title: Re: Backface Culling?
Post by: Paleohunter on August 04, 2017, 12:44:41 PM
Thank you, Dries! That was exactly what I needed, worked like a charm. The original thread I found had you insert an emissive node instead of a color invert node.

Thanks again!
Title: Re: Backface Culling?
Post by: cjwidd on September 18, 2017, 08:34:48 PM
I'm using Keyshot 7 and there is no Experimental Features option under the Advanced tab in the preferences window (?)
Title: Re: Backface Culling?
Post by: Esben Oxholm on September 19, 2017, 12:10:06 AM
Quote from: cjwidd on September 18, 2017, 08:34:48 PM
I'm using Keyshot 7 and there is no Experimental Features option under the Advanced tab in the preferences window (?)

Hi cjwidd.

For some reason the experimental features has been removed from the KS7 UI.
I haven't tried this myself but you should be able to make it appear by going to your KS7Settings.xml file
and setting <experimental_features bool="false"/>     to     <experimental_features bool="true"/>

Hope it works.
Best,
Title: Re: Backface Culling?
Post by: cjwidd on September 19, 2017, 02:59:28 AM
Quote from: Esben Oxholm on September 19, 2017, 12:10:06 AMI haven't tried this myself but you should be able to make it appear by going to your KS7Settings.xml file
and setting <experimental_features bool="false"/>     to     <experimental_features bool="true"/>

Where is this file located?
Title: Re: Backface Culling?
Post by: INNEO_MWo on September 19, 2017, 03:37:38 AM
Quote from: cjwidd on September 19, 2017, 02:59:28 AM
Quote from: Esben Oxholm on September 19, 2017, 12:10:06 AMI haven't tried this myself but you should be able to make it appear by going to your KS7Settings.xml file
and setting <experimental_features bool="false"/>     to     <experimental_features bool="true"/>

Where is this file located?
In Windows it's located in the documents folder as keyshot7.xml
On a MAC as Esben said.
Title: Re: Backface Culling?
Post by: cjwidd on September 19, 2017, 05:59:18 AM
No change, unfortunately
Title: Re: Backface Culling?
Post by: Esben Oxholm on September 19, 2017, 06:38:40 AM
Have you checked the graph?
Maybe the experimental nodes becomes available without the need to check the experimental features checkbox.
Title: Re: Backface Culling?
Post by: INNEO_MWo on September 19, 2017, 09:09:52 AM
Just check the lighting tab on the bottom. If there are more than product and interior mode, than experimental features are available. Also in the material graph in the utilities you'll find the new ray mask as well the backside-surface mask.

The preferences doesn't show the "experimental option"


Cheers
Marco
Title: Re: Backface Culling?
Post by: cjwidd on September 19, 2017, 01:16:13 PM
I definitely appreciate the advice, but I am afraid these features are still not available. I am using an education version, which according to the product comparison, should not make a difference.



Title: Re: Backface Culling?
Post by: cjwidd on September 19, 2017, 07:44:48 PM
Quote from: MWo on September 19, 2017, 09:09:52 AM
Just check the lighting tab on the bottom. If there are more than product and interior mode, than experimental features are available. Also in the material graph in the utilities you'll find the new ray mask as well the backside-surface mask.

The preferences doesn't show the "experimental option"


Cheers
Marco

This seems like a fairly serious inconvenience, but perhaps I have missed something?
Title: Re: Backface Culling?
Post by: DriesV on September 20, 2017, 02:42:50 AM
I just tested this with the EDU version and experimental features work perfectly after editing the xml file.
Are you sure you saved the xml file and that you weren't running KeyShot while making the change?

Dries
Title: Re: Backface Culling?
Post by: Esben Oxholm on September 20, 2017, 03:33:18 AM
When I try on mac, I get a critical error, that it can't load the file.
Any suggestions on how to avoid this?

KeyShot is closed while editing and saving the file and I don't edit any other lines in the xml.
Title: Re: Backface Culling?
Post by: hstokholm on September 20, 2017, 03:41:45 AM
Esben: Looks like you are using the wrong brackets around the "true" value. It can happen when using TextEdit.
Title: Re: Backface Culling?
Post by: cjwidd on September 20, 2017, 04:31:07 AM
Quote from: DriesV on September 20, 2017, 02:42:50 AM
I just tested this with the EDU version and experimental features work perfectly after editing the xml file.
Are you sure you saved the xml file and that you weren't running KeyShot while making the change?

Dries

I'm really not sure what to say, I agree it is unusual. I checked the file in two different text editors - just to be sure - and the bool for experimental features is set to true. The file was edited outside of Keyshot while Keyshot was closed. The 'surface backside mask' utility node does not appear in the material graph drop-down menu. Is there is some other set of conditions (e.g. settings that need to be enabled) that I'm unaware of?

Title: Re: Backface Culling?
Post by: Esben Oxholm on September 20, 2017, 06:56:08 AM
Quote from: hstokholm on September 20, 2017, 03:41:45 AM
Esben: Looks like you are using the wrong brackets around the "true" value. It can happen when using TextEdit.

Thanks! That was exactly the case. Now it works. Good catch!
Title: Re: Backface Culling?
Post by: cjwidd on September 23, 2017, 02:45:03 AM
The KS7Settings.xml was stored in C:\Users\Public\Documents\KeyShot 7, not in the default Documents folder. I adjusted the file and the experimental features are now available.