Need to composit renders, where is ground plane alpha in nXt 5?

Hi there,

As the topic says: Need to composit renders, where is ground plane alpha in nXt 5?

Has this functionality been removed? I have updated to the latest release and I cant find the ground plane alpha option anywhere. I’m assuming its just hard to find as it would be colossally stupid to have removed it as an option. Getting very desperate on time, need to find out quickly.

Thank you very much,


Did you mean this?

Yes, there should be a tick box for alpha channel but it’s gone. This existed in previous versions of nXt. If it’s gone then nxt5 if effectively useless for me and I will need an alternative.

Actually i’m using the last Flamingo nXt 5.5 for rhino 6 and 5.0 for rhino 5 it’s working that same pic.

This what I am looking for:

In the older Flamingo you could render with an invisible ground plane, complete with shadows. If you saved the image as a png the transparency remained. It is then easy to drop ypur render into a background in photoshop, and you have realistic shadows under the object. See the attached car render. I can not find how to achieve this with nxt 5. I have downloaded and installed the latest version yesterday. I found a thread on the forum from two years ago where a McNeel guy said it was a bug and would be fixed.



To be fair, he wrote:

I have filed this bug […] and hopefully we can have a solution to it soon for you.

The YT item (FL-6159) clearly hasn’t yet made it to the top of the priorities list - possibly partly because there is a script that you can run to make this work. Have you tried that script?

I have not tried this. I am not familiar with scripts and running them, would not really know where to start. Is there a tutorial?

Thanks a million,


To test the script, download it here and save it to a folder that makes sense to you. Then, use the RunPythonScript command and browse to the script that you just saved.

If this works and you need it often, you can make a keyboard shortcut, an alias, or make a toolbar button for it. The macro that you need to use is stated in the YT item but let us know if you need more help with that.


That works perfectly, thank you very much :slight_smile:

Alpha channel still not there with the ground plane.
Do I have to have IT run that script? We are locked down from an admin standpoint.
I need shadows on a background image.
V 5.0.16334.11523, rev 10578 This Flamingo is up-to-date

Hi - no, you will have to run that script inside of Rhino using the Rhino RunPythonScript command.
For instructions with more details, please see the discussion above.

Thanks much. I’ve set that up and it’s like the old days, background pictures with model driven shadows.