I thought I figured out a great way to Just render a basic shadow, and it still worked out OK, but not great.
But my first thought Should work. Create a new model set, and don't link materials. Apply a black emissive material to the entire thing. Turn off visible to camera, reflections, refractions.
And yay, a nice shadow on the ground. But...wait. There are a Bunch black pieces all over my model.
My Guess on what is happening, is it's visible where pieces of the model touch, but not sure.
I ended up just making the emissive plain white. Then just eliminate the white later.
The issue still is that you get half pixels that just don't really work. It's an antialiasing issue. That's why I Really want the entire shadow under my object. That way, no worries of background leaking through that selection.
The reason I did this, is it's for package rendering where the thing is cut out from the background. The lighting on the product ended up a bit dramatic. But I don't want long shadows. So I also created a Very boring environment with just one light up top to cast a Really boring shadow. I was hoping that would be less work, and potentially look better than creating a shadow in photoshop. For the time being, I was wrong.
