libRainworldmc
libRainworldmc is a small Fabric library for Minecraft 1.21.1 that other mod developers can build on, from GUI widgets to shader and text tools.
What it does
The library bundles a set of GUI widgets, among them a no-texture button for the main menu, plus modular settings screens and a config system that selects tools by biome. Its nine slice tiling system supports the widgets and a custom server MOTD renderer, and advanced text manipulation is included for the same purpose.
A Rain World atlas system and a shader rendering layer sit beside these parts. The shader code offers framebuffer capture and works with Iris Shaders, and it can render quads in the world using core shaders. The project changes little about the game itself and is meant for developers who use it as a base.
Installation needs Fabric API, Geckolib and Iris Shaders, all three required. A server running it needs every connecting player to have it too. Files are published for Fabric only, for 1.21.1, and the latest build is 2.0.5, released 2026-10-15 on the beta channel, under the MIT License.
Key features
No-texture GUI button
A button that draws without a texture file, with a menu attempt that places it on the main menu screen.
Modular settings and config
Settings screens and a config system are built from modular selection tools, including a biome-based tool.
Nine slice tiling
Nine slice tiling supports the library widgets and a custom server MOTD renderer, so panels scale without distortion.
Shader rendering with framebuffer capture
Rain World shaders and framebuffer capture render quads in the world with core shaders and work alongside Iris Shaders.
Compatibility
Latest build for each game version and loader.
Only full game releases are shown. This mod publishes no snapshot builds.
Requirements
Dependencies declared by the latest file for each loader.
Required 3
Use cases
Who it’s for: The library is aimed at mod developers who need GUI widgets, shader helpers or text tools for their own Fabric projects on 1.21.1.
How it compares
Kaboom Library is also a Fabric library, with Client and server environment and the MIT License, but it is published for 1.21 and is not open source. Luminance is a Fabric and Quilt client library, open source under the GNU Lesser General Public License v3.0 only, with files for 1.20.5 – 1.21.11.
| Mod | Loaders | Game versions | Environment | Updated |
|---|---|---|---|---|
| libRainworldmc | Fabric | 1.21.1 | Client and server | 2026-10-14 |
| Kaboom Library | Fabric | 1.21 | Client and server | 2026-06-26 |
| Luminance | Fabric and Quilt | 1.20.5 – 1.21.11 | Client required, server optional | 2026-07-28 |
Questions
Does libRainworldmc need Fabric API?
Does the server need libRainworldmc?
Which game versions does libRainworldmc support?
In the catalog
libRainworldmc is one of 3,514 Library mods on ModsFinder, and one of 2,348 Library mods for Fabric. 32,366 mods support Minecraft 1.21.1.
Similar mods
What the author says
This library adds a bunch of GUI widgets, viewable through the no-texture button in the main menu, an attempt at a modular settings and config system, a modular selection tool system based on the biome tool and a bunch of code that implements a version of the Rainworld atlas system into minecraft. There's also a…
Official listing
- Modrinth page
- modrinth.com/mod/librainworldmc
- Owner
- BrickCraftDream
- Published
- 2026-02-23
- Updated on Modrinth
- 2026-10-14
- Facts verified
- 2026-10-15