Issues with lighting a 3D scene

edited December 2016 in Pro Support

This one is proving particularly frustrating.  I'm sure it's something stupid I'm overlooking, but...

Anyway.  I've got a composite shot in my project with a bitmap set as a 3D plane and a bunch of models, all 3D unrolled.  I drop a light into the space and... nothing.  Directional, spot, ambient, none of them do anything.

I'd assume the models weren't set up correctly, but they are; I'm using them elsewhere in the project in different comps, and they're being lit just fine.  In fact, if I copy-paste one of the lit objects from the other comp into this one, it shows up lit and reacts to whatever light I've put in the scene.  If I drop a blank, colored 3D plane into the scene, it's lit properly as well.

I've gone over the settings of each model in the scene with a fine-toothed comb a dozen times over, but there's absolutely no difference between the lit version and the unlit version.

What could I possibly be doing wrong?


  • edited December 2016

    Okay, I figured it out.  This was a fun one, and I'm sure somebody knows why it was doing this. 

    The 3D plane was the culprit.  That, and possibly the 2D video layer I'd overlayed on top of the scene.  If I pushed the 3D plane (which was serving as my floor) all the way to the bottom of the render stack, and made sure the 2D layer was above the master camera in the scene, my models would suddenly get lit.  The reason the copy-pasted model was working fine was, of course, because it would get pasted into the stack above the plane, whereas the other models were below it.

  • It's an awesome feeling isn't it when you figure it out yourself ;)

    Well done!

  • Steve, "3D space" in Hitfilm is really "3D spaces-plural." 2D layers (keyed video, grade layers, etc) force a render of underlying layers, but Hitfilm renders bottom to top of layer stack. So lights above a 2D layer disconnect from models below it. Also, if you have two 3D models set to 3D unrolled, but have a Grade Layer between them they won't properly occlude.

    Sometimes this is a pain, sometimes its an advantage. Sometimes you want to seperate your 3D elements into seperate "spaces." 

  • edited December 2016

    So lights above a 2D layer disconnect from models below it.

    This was definitely part of the problem.  I know to keep all of my 3D stuff underneath the 2D layers for precisely that reason, but for some reason it wasn't twigging to me that the light and the camera not being there as well was an issue.

    I should stop trying to make video at 2am.

  • Shouldn't affect the camera, just lights. 

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