Uploaded an experimental editor that supports this.
Whichever graphic set is actually selected in the Level Properties menu will be (a) the level's primary graphic set (the one that determines eg. minimap color, normal vs xmas lemmings, etc), and (b) the one which pieces appear from when adding / changing a terrain or object. However, try placing a piece, then changing to another graphic set.
A single level can currently use pieces from up to 256 graphic sets, whether or not that includes any from its "primary" set.
For those who just want to see it in action, see the attached level. Note that this level WILL NOT WORK on V1.43n-F; it will only work on the recent experimentals. (You don't nessecerially need the
very latest one; the player-side support has been there for a while.)
Use this feature wisely.
Things to look out for:
- Any cases where this isn't working properly
- Any remaining artifacts from support for other engines
- Issues with loading levels from other engines - this should still remain possible!
Known issue:
- If you load a LVL file from an older editor version that contained pieces that had been locked, they'll no longer be locked upon opening with this version.
Also, I still haven't added support for rotating objects. I'd also like to add a "Download graphic sets" menu similar to what Flexi Toolkit has / what the player does automatically if enabled.