Different Lights on in Different Viewports?

Does anyone know how to show shadows from only one light in a perspective in one viewport, and shadows from only another light in another perspective view in another viewport?

This post yesterday outlined everything I’ve tried, but got no replies. I’ll simplify it now to say that despite 6 hours of experimentation and web searches, nothing in this regard is operating for me as the settings seem to imply. “Show lights on layers that are off” has no effect on the shadows, and my attempts to set up a View Mode with only one of the lights active in a lighting scheme results in shadows which either do not match either placed light or show shadows from both lights.

Sorry nope. You could set up different view modes with different directional lighting, that’s it. I guess the question would be, what are you trying to do?

Thanks Jim. That’s exactly what I thought I could do, because the space I have modeled needs different lighting to illustrate each of two different perspective viewports on my layout, I thought I could set up a View Mode for each light, just as you suggest. Sorry the below is long, but there’s a lot of failure to recount, with a lot of settings.

First I set up 2 lights, each creating the shadows desired for one of my two different viewports. But in Options>ViewModes>“ViewModeName”>LightingScheme>LightingMethod, “Default Lighting” and “Custom Lighting” result in shadows that don’t match the ones I’ve created and don’t respond to any movement of the lights. Only “SceneLighting” creates a view mode that will accurately reproduce these shadows, but only from both lights at the same time - I’ve found no way to deactivate only one light in any one viewport: Any settings in the Lights tab affect both viewports, and any settings referring to viewport-specific layer activation or light selection in the tabs affect only the display of the individual light objects, not the presence of the shadows the lights cast.

All these settings seemed to offer Viewmode-specific and/or Viewport-specific controls of which lights are active, but it seems that they don’t.

Either a) I’m missing something, b) there is no way to do this, or c) something’s not working properly.

Hello - I think, if I understand, you need to set up one light and make a display mode using scene lighting and then set up a different light and set up a separate, but similar, display mode using that light. You’d then set each viewport to use the appropriate display mode.

-Pascal

Thanks for the reply, Pascal, but I didn’t get email notification of it and am currently on Chat with Scott. We are both flummoxed on how to do this though the settings seem to suggest that it’s p;ossible.

we are trying the method you recommend, which I have tried for hours prior to the post. We can’t get it to work.

Hello - see how these modes work - I made them as I described. It looks like you may need to hit the ApplyNow button for the lighting while in that new mode, for it to kick in… it seemed a little odd but it worked.

-Pascal

LightFromLeft.ini (12.3 KB)
LightFromRight.ini (12.3 KB)

If you don’t need them to be in action at the same time you probably could use snapshots with the lights and views set as you want, then activate the snapshot you want to look at.

Thanks, Pacal but I have many times in the last couple of days been at the point where I have different lights on in different viewports using this method. The problem is that they will not remotely match the careful positioning/targeting of lights already positioned and targeted in the project when “Use Scene Lighting” is chosen,and there is no clear method of targeting them once they are created by that method. The CustomLighting input fields seem to be using a particular Cplane neither Scoitt nor I have been able to recreate in a model where the lights are setup.

Thanks for the suggestion, Nathan, but unfortunately for my objectives, SnapShot seems only to apply saved light states globally to all viewports. So yes, they can be used to preview different sets of light states (in all viewports), but not create different states from viewport to viewport and create a printable layout with windows showing an updatable model in different light conditions.

Yeah - once set up the lighting follows the camera, its not static. I guess this system could work if the view is the same as when the light was added. e.g. an elevation view.

-Pascal

Thanks, Pascal, but I don’t understand. I have added a light in a locked perspective view and edited the lights points in that view to achieve a lighting angle which creates shadows as required. Customize>UseSceneLighting for the View Mode changes those shadows drastically in this same viewport window. I have tried this both with the perspective’s Cplane set to World Top and set to View, and the results are the identically incorrect on each setting.

I see - so without changing the view, you get a different shadow direction once it is applied to the display mode (and you delete the light)?

Testing… yeah, I see exactly what you mean. Oi. Trying V5 just for comparison… i.e. did we ever do that right?

-Pascal

It could be at least workable if we could understand what coordinate system the “Use Scene Lighting” was using and implement that system when placing the lights. That ought to be reverse-engineerable?

You’ll notice that it’s loading the correct target information in the “direction” fields, but that only establishes one point: where is it putting the source?

I’d think so, but it is not clear to me yet either. I’ll see what I can find out… off hand it looks incorrect to me, as is, but it seems to have been that way since for ever…

It should lock the lighting to the camera as it is when the mode is made. I think.
https://mcneel.myjetbrains.com/youtrack/issue/RH-47215

-Pascal

It might be worth saying that of the View Mode Lighting Method flyout choices, only “Scene Lighting” creates a view mode that will accurately reproduce these shadows (but only from both lights at the same time - I’ve found no way to deactivate only one light in any one viewport). If whatever it’s doing to acquire that information were duplicated in Customize > “Use Current Scene Lights” it seems the intent of the setup would be fulfilled (and so could my objectives.)

Okay, I was wondering what your actual goal was. I guess if I had a task like that to do I’d have separate files for the different setups and merge PDFs in InDesign or the like.

Thanks Jim. Working in AutoCAD for years, I’m used to having a perpetually ready-to-print regenerating layout that automatically updates many changes. I don’t feel that the increased steps required exporting to layouts in another programme would equip me to compete.

I am going to assume for now that it isn’t possible to do this unless I - or someone at your end - can figure out what coordinate system is being used in CustomLighting. I might give that a try as it seems like there’s some sort of logic to it, and with that cracked there’s a workaround within Rhino.