This changelog describes what changed on the 1.21.1 branch since master (1.20.1).

Added

• Minecraft 1.21.1 and NeoForge 21.1 support.
• Fabric support with platform-specific entrypoints, services, model discovery, networking, render events, static model support, and metadata.
• A multi-project layout with common, neoforge, and fabric modules.
• Shared platform services for lifecycle hooks, registration, networking, render events, shader registration, model discovery, static model integration, and loader checks.
• ChaosLibBootstrap as the common initialization entrypoint for networking, examples, client config, shader registration, resource reloads, render hooks, Sodium compatibility, and static model discovery.
• ChaosClientRenderRegistrar for GPU world render dispatch, world light-volume updates, and multipart debug rendering.
• ChaosNetworkRegistrations for multipart bone sync, melee hit hints, and use hints.
• ChaosExampleRegistrations and bundled example content for animated entities, multipart entities, and procedural block rendering.
• Public dev.elifian.chaoslib.api.iris API for optional Iris shader-pack integration.
• Iris-aware render-layer wrapping for entities, block entities, outlines, and explicit custom render phases.
• Iris-compatible custom shader support through IrisCompatibleShaderInstance.
• Dedicated depth-writing shadow render-layer support for translucent and custom entity renderers under Iris shader packs.
• Shader-pack skinning injection for ChaosLib GPU-rendered geometry.
• Shader-pack program compilation and fallback handling for ChaosLib GPU rendering.
• GPU pose retention with shared pose arenas, pose slot stores, pose resampling, and the rendering.retainedGpuPoses option.
• Batched pose sampling so a frame's poses can be sampled in one dispatch per mesh and animation.
• Shared GPU poses for objects that animate in step.
• Streaming instance data through a ring of GPU buffers.
• Instanced GPU render data storage and shader-pack render dispatch support.
• Static geo model discovery on both loaders.
• Fabric static model discovery metadata and Fabric static model rendering path.
• Sodium compatibility surface, Sodium options integration, GPU skinning controls, and debug overlay.
• Chloride compatibility bridge.
• Fabric and NeoForge implementations for static geo baked models.
• Multipart hit hint handling in the same tick that requested the hint.
• Swing-strength capture before vanilla resets the value.
• Centralized build output and run directories.

Changed

• Loader-independent code, resources, tests, and mixins moved into :common.
• Loader projects reduced to platform packages, service implementations, metadata, and bridges.
• Old direct init classes were replaced by service-backed common init classes.
• ModClientRegistries, ModNetworkRegistries, and ChaosShaderRegistrar were replaced by the bootstrap, render registrar, network registrar, and platform shader services.
• Embeddium compatibility naming was replaced with Sodium naming.
• Obsolete Embeddium config flags were removed from the compatibility surface.
• Legacy shader-mod terminology was normalized to Iris on the 1.21.1 codepath.
• Entity and block-entity renderers now submit Iris-aware render layers.
• GPU shader-pack rendering now tracks Iris phases, shadow passes, rendered entity ids, block entity ids, and item ids.
• Block-entity state handling and world render stages were updated for Fabric.
• Fabric render hooks, static model path, and model discovery now match the NeoForge feature surface.
• Static model baking and render-state handling were updated for the 1.21.1 loader split.
• Multipart entity networking and interaction flow were updated around explicit hint packets.
• GPU animation dispatch now runs outside the render state where possible.
• GPU pose storage now grows with explicit compute-write flushing.
• Build scripts now produce loader-specific artifacts into the shared root build/libs directory.
• Mod version changed to 1.1.0.
• DESCRIPTION.md now describes ChaosLib as a Minecraft animation and rendering library with Sodium and Iris compatibility.

Removed

• The old single-loader source layout.
• Forge-only src/main ownership of loader-independent code.
• Legacy Embeddium-named compatibility classes and mixins.
• Legacy shader-mod mixin and compatibility resource names on the 1.21.1 codepath.
• Loader-side copies of common tests and resource files after the multiloader split.
• Obsolete init classes that were replaced by the common bootstrap and platform services.