OK! Here's my example:
Bolt with Negative Space.skp (132.0 KB)
A few disclaimers first:
* Yes. It is huge --- YUUUUGGGGEEEEE! In order to avoid the small face problem, I modeled it in meters!
* Yes, I did use a couple of layers - so you can quickly turn visibility on/off for the bolt separately from the negative space
* No, I did not try to model this realistically. For instance, I don't know if I've left enough room for a socket wrench around the head, nor did I leave any negative space for a nut/washer on the other end. I created this to illustrate my negative space idea - not to create an actual bolt component!
The general thrust of my idea, explained (perhaps poorly) in the original post, is that I'd like to see the negative space idea added to Sketchup. While it could be used independently, the use cases I've been able to think of all involve using the negative space in conjunction with a real model (like a bolt, or a window) where use of the real model implies "clearing away" parts of the rest of the model in order to insert your component - hence my restriction that it only be available as a sub-component of a glued, cutting component. (I include the "glued" criteria only because currently, in SketchUp, you can't make a cutting component that isn't glued.)
While in this conversation we have all (I think) identified the Face Cutter extension as a possible (partial) solution to my recommendation. Examining the example I uploaded, here are a few reasons that the Face Cutter extension is insufficient:
If I used Face Cutter with this, it would cut a hole with the widest diameter - that of the larger part of the negative space around the bolt head. What I want is that something that would cut the widest diameter in the direction of the bolt head and the smaller diameter in the direction of the bolt body!
As supplied, there are two overlapping coplanar faces (the bottom of the bolt head and the 2d "donut" where the negative space transitions between the two diameters. These (as expected) Z-fight on display. In use, should my idea be adopted, I would recommend that SketchUp ignore (for display purposes) faces of the Negative Space that are coplanar and overlapping with faces both within the component and with the rest of the model. Otherwise (when SketchUp adds geometry to replace the "holes" created by the negative space) all the created geometry will z-fight with the negative space!
The example shows a negative space that is "outside" of the item being modeled (except for the coplanar faces), but this isn't necessary - in fact, it might be a limitation! Why? Imagine a model of a manufactured window - most of it is contained inside an imaginary box representing the rough opening, but it also include exterior trim of some sort which is not within the rough opening. Since it's relatively common knowledge that you have to leave clearance to install a manufactured window from the exterior, I don't see the need to require such complexity in a window model - just using the negative space to define the minimum rough opening is enough.
While it's becoming apparent that most of what I want can be done using existing tools and extensions, I remind all that I'm hoping for a solution that allows you to transform (move, rotate, scale) the real item represented by the component and the previous "cuts" would be magically healed and new ones created after the transformation - much as the current ability of a component to cut a single face works.
I'm especially hopeful that this would, in time, result in a number of high quality components becoming available in the 3d warehouse that could be used for the novice wanting to use SketchUp to brainstorm a model quickly (as was the case with me - I started using SketchUp for Tiny Home modeling for personal use). For me, it was the Solid Tools that convinced me to spring for Pro instead of Make. For others? Perhaps they'll be inspired to spring for Pro in order to customize Dynamic Components with Negative Spaces that they've downloaded from the 3DWarehouse!