Litematica

The mod reads and writes schematic files and renders them in the world so the player can compare a plan with what is built. It covers the main features of an older schematic tool, with the exception of a printer, which the author leaves to extension mods. Required libraries are MaLiLib and Ornithe Standard Libraries. Published for Fabric, Forge, LiteLoader, Ornithe and Rift across 50 release versions spanning 1.12 – 26.3, with snapshot builds as well. Only the client runs it, and the code is open source under the GNU Lesser General Public License v3.0 only.

Default hotkeys open the main menu with M, the configuration menu with M + C, and the Schematic Placements list with M + P. Other keys toggle all rendering with M + R, schematic rendering alone with M + G, and the tool item with M + T. The Schematic Verifier opens with M + V, and the Area Editor with the numpad multiply key. Key bindings may differ on non-QWERTY layouts. Rendering does not work properly with shaders in 1.21.3 and later, so shaders should be disabled while schematics are shown. Some servers may flag the placement feature as cheating, so its use should be checked against each server's rules before use.