LDLib2

A modern Minecraft modding library for UI, rendering, synchronization, persistence, and in-game editors.

Documentation | Java Integration | UI Guide | Discord | CurseForge | Modrinth

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LDLib2 is a complete rewrite of the original LDLib, redesigned around modern Minecraft and NeoForge development. It gives mod authors a higher-level foundation for building UI, in-game tools, renderer-backed content, synchronized data, and persistent runtime systems without rebuilding the same infrastructure in every project.

Feature Highlights

LDLib2 UI Build Minecraft screens with Taffy-powered layout, LSS stylesheets, reusable components, XML definitions, data bindings, RPC events, and HUD overlays.	Data Synchronization and Persistence Annotate fields with @Persisted, @DescSynced, and RPC helpers to generate NBT IO, codecs, dirty-field sync, and packet flow with minimal boilerplate.
Node Graph Toolkit Create in-game graph editors with nodes, ports, wires, variables, subgraphs, blackboards, undoable commands, and resource-backed graph assets.	In-game Editor Framework Build Unity-, Blender-, or Blockbench-style tools with dockable views, project files, resource browsers, inspectors, history, settings, and custom editor panels.
Configurable Turn annotated Java objects into inspector-ready property panels, including ranges, selectors, lists, resource locations, search fields, undo history, and persistence.	Rendering and Integrations Use LDLib2's shader, texture, model rendering, scene, and editor utilities together with common modding workflows such as JEI, REI, EMI, KubeJS, and Java plugin entry points.

Java Integration

LDLib2 is published to the FirstDark Maven snapshots repository.

repositories {
    maven { url = "https://maven.firstdark.dev/snapshots" }
}

dependencies {
    implementation("com.lowdragmc.ldlib2:ldlib2-neoforge-${minecraft_version}:${ldlib2_version}:all")
}

For LDLib2 versions before 2.2.1, disable transitive dependencies and add Yoga manually:

dependencies {
    implementation("com.lowdragmc.ldlib2:ldlib2-neoforge-${minecraft_version}:${ldlib2_version}:all") {
        transitive = false
    }
    compileOnly("org.appliedenergistics.yoga:yoga:1.0.0")
}

Recommended project variables:

minecraft_version=1.21.1
ldlib2_version=2.2.26

LDLib Plugin Entry Point

Create a plugin class when your mod needs to register LDLib2 resources, integrations, or startup hooks.

import com.lowdragmc.lowdraglib2.plugin.ILDLibPlugin;
import com.lowdragmc.lowdraglib2.plugin.LDLibPlugin;

@LDLibPlugin
public class MyLDLibPlugin implements ILDLibPlugin {
    @Override
    public void onLoad() {
        // Register LDLib2 extensions here.
    }
}

Quick UI Example

This creates a small ModularUI with a label, a button, and a styled root element.

public class MyScreenUi {
    public static ModularUI createUi() {
        var root = new UIElement()
                .layout(layout -> layout.paddingAll(7).gapAll(5))
                .style(style -> style.background(Sprites.BORDER));

        root.addChildren(
                new Label().setText("My First LDLib2 UI"),
                new Button()
                        .setText("Click Me")
                        .setOnClick(event -> {
                            // Handle the click here.
                        })
        );

        return ModularUI.of(UI.of(root));
    }
}

For a full walkthrough, see the UI Getting Started guide.

Developer Tools

If you develop with LDLib2, install the LDLib Dev Tool IDEA plugin for editor assistance around LDLib2-specific files and annotations. The Java Integration guide covers code highlighting, syntax checks, jump-to-definition, autocomplete, and annotation support.

Migrating from LDLib

LDLib2 is not a small patch over LDLib. It removes old systems and rebuilds the core architecture for Minecraft 1.21+.

• Legacy UI and outdated framework pieces have been removed.
• UI layout, styling, events, and data flow have been redesigned.
• Documentation and examples are written around the new architecture.
• Compatibility work focuses on modern NeoForge and current modding integrations.

Links

• Documentation
• GitHub repository
• CurseForge project
• Modrinth project
• Discord community
• Original LDLib

License

LDLib2 is licensed under the LGPL-3.0 license.