I like the idea, it just requires us to go through them all by hand which might be a bit rough (some of the models don't have a proper hierarchy; the dragon and most newer models might be the only ones that really do).
An alternate method I had thought of was basically a separate "tool" that draws the full model as transparent, and you wipe your finger/"draw" over the pieces you want to be visible, then hit an OK button to switch back to drawing. Might be a bit easier especially if it's combined with a keyboard shortcut on desktop.
PMCSkin3D Auto-View
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1. Tap the 3 line bar on the top right of the screen (On PC, simply navagate to the sidebar on PMCSKIN3D.)
2. Tap/click 'Visible Parts'
3. Untick every box under 'Visible Parts' except for Head and Jaw, which usually takes a while.
4. Navagate out of the sidebar (tap on the right side of the screen on mobile)
5. Tap the 'Zoom In' button about 30 times (scroll the zoom slider down on PC)
And only then can you start drawing on the head.
Here are the theoretical steps with the Auto-Zoom feature:
1. Tap the 3 line bar on the top right of the screen (On PC, simply navagate to the sidebar on PMCSKIN3D.)
2. Tap/click Auto-View
3. Under the dropdown menu, tap/click 'Head' (and this should also automatically zoom too)
And you're done!
Essentially what the sidebar/menu would now look like is:
(This would be the drawing tools options up here)
| Mirror |
| Brush Stroke |
| Visible Parts |
| Auto-view |
And this is what the autoview menu should look like (for cow model)
[ ] Body
|--- [ ] Main Body
|--- [ ] Utter
[ ] Head
|--- [ ] Main Head
|--- [ ] Horns
[ ] Legs
|--- [ ] Front Left Leg
|--- [ ] Front Right Leg
|--- [ ] Back Left Leg
|--- [ ] Back Right Leg
Granted, I'm limited with what I can show the menus as because I'm limited to ASCII text.