You're wellcome. In fact, I thank you for showing interest in my suggestions. This way there is a slight chance that the future versions of Physion would partly work the way I'd like.
No offense but honestly at the moment I'm using another application (because I don't quite know how to use Physion) but I'm having a hard time with that application, due to 2 aspects of the lack of layers:
1. It's hard to select an underlying body; you have to move the top ones behind. Not to mention that there's no way of easily change the z value of the selected body (incrementally) -- you can only place it either on top or at the bottom of the "stack".
You could say that this can be very well mitigated without layers, by simply clicking more times and cycling through the overlapping bodies, like in Incredibots (which BTW has a smooth workflow for the few features it has
But what when several bodies have the same shape and size? How can you tell which one is selected?
2. The second aspect is visualization. Suppose you d/l a scene and look at an object having more overlapping bodies. How do you figure it out? There are cases when you have to cycle somehow between the bodies, just to see it through.
So, the aspects are building and understanding. Moreover, what we conceptualize in mind can be easily "materialized". Imagine what is the difference between thinking of somebody and looking at her/his picture
. Or computing 2-digit multiplications mentally.
Yes, an object can be in several layers
When a body has more "layers" of collision, it shows up in more of our layers (in each of them. This assuming that you can view individual layers content). You could make it so the scene is more realistic by allowing a body to only span consecutive layers, so not to have "trans-dimensional" bodies
. In that case, the no. of layers would give the width of the body (imagine an object seen into the Y axis).
About the layers, I'd personally prefer not to call them "collision layers" but more like "physical layers", because unlike the former which hardly are layers, due to excessive abstracting, and are restricted to collision, "now" there's more to them, they are physical, concrete, we can see the width of the body, like slices, and you could add to the realism even further, by having the option that the width of the body would influence the mass
You could create objects simultaneously in several layers by selecting them before creation.
When you create a body and want it to have more (physical) layers, you first select the layers that the body would span, then
build the body which now is as thick and influential as the no. of layers.
I said "select" the layers, because by default only one layer (generally the top-most) is selected and you'd have to hold CTRL to select multiple layers.
You mentioned AutoCAD layers. You're right. I think thumbnails for every layer would be more difficult, as you'd have to draw multiple times. Nevertheless, the AutoCAD layers -> thumbnails upgrade would make just an as huge leap as a collision layer -> AutoCAD layer, or if you will, like the evolutions from command-line games -> 2D games and 2D games -> 3D games
. I'm not implying that you should go for thumbnails, I only state what would be the most intuitive and expensive system like, conceivable.
The thumbnails and Y axis view are more like ideas rather than suggestions, I know there's a long way...
If you've read through to see this, I thank you again