Sculptory

For Minecraft 1.21.1 with Fabric Loader 0.16.14+ and Fabric API 0.116.4+1.21.1, as 0.4.0-beta. Network protocol 6, as 0.4.0-beta: the two work together, with the differences at the end. Released with the first NeoForge mod and Paper plugin (below), built on the same code, so the fixes and changes here are in them too.

New

• Building by hand goes into the history by default. Builder mode's new ninth power, Record, is on from the first start: in Creative (with the builder permission on servers), every block you place or break and every item frame, painting or armor stand you hang, place, change or break is one undo step. Buckets, bone meal, tools used on blocks and other item uses stay vanilla's (rules). Switch Record off in the G ring to play unrecorded; that is remembered.
• Item frames, paintings and armor stands are history steps with a builder power on: hanging, placing, putting an item in a frame, dressing a stand or breaking any of them is one step, undone and redone like a block. Where builder mode would refuse a block, nothing is placed. Mirror does not copy them.

Fixed

• Placing blocks in Survival with a builder power on: a player in Survival, or without the builder permission, with a power still on could not place blocks on a server with Sculptory. Builder mode now steps in only while it acts for the player.
• Building by hand with editing switched off on the server (editingEnabled false, or a broken server.json): every place and break was refused. Clicks now go the vanilla way, the editor can't be opened (B says "Editing is off here"), and a reload that switches editing on gives both back.
• Frames and paintings no longer drop off when their wall goes: an edit that removes the block a frame or painting hangs on takes it into its step, and undo hangs it back with its item. Undoing a wall takes along the frames hung on it since; redo hangs them again, also after a restart.
• Surface mode on thin walls: Raise and Lower work the side you aim at on any wall 3 or more blocks tall, however thin; a wall one block thick was often worked from above. Single blocks and steps up to 2 blocks high still count as ground. Flatten's plane and the cursor ring follow the same rule, so Flatten aimed at a wall flattens along its face.
• Surface Smooth keeps thin walls and slabs: walls 3 or more blocks tall and one-block slabs keep their ends and corners, and Smooth no longer piles blocks against a thin wall or a slab. Bumps, spikes, pillars and ridges under 3 blocks still smooth away.
• Lines and roads are the same wherever they are built: Generate's Line and Road work from their first point, so the same shape moved by whole blocks has exactly the same blocks. Straight lines (Line, Sweep, Extrude along a path, the Shape brush's Line, a Hanging line's chord) are exact: a half-block-per-block climb steps at every other block. Curves are as in 0.4.0-beta.

Changed

• New jar and version form: sculptory-fabric-0.5.0-beta+1.21.1.jar (was sculptory-0.4.0-beta.jar). The build id, version plus Minecraft version, is what the mod list shows and what client and server show each other. Take the old jar out of mods.
• Generate roads: curved roads end in their true end direction, a road whose last two points share a column keeps a round end, straight roads round half-block steps the same wherever they are, and Use Stairs and Slabs on a 45° road always steps along x.

With a 0.4.0-beta client or server

• A 0.4.0-beta client on this server predicts Surface Raise, Lower and Smooth near walls the old way: its preview can differ, the server's result is what is built. Update clients and server together.
• On a 0.4.0-beta server, Record is greyed out ("needs a newer server") and plain clicks are recorded only with another power on, as before. A 0.4.0-beta client on this server has no Record and works as it did.
• Going back to a 0.4.0-beta client forgets a switched-off Record: it is on again when you return.