The dev.anvilcraft.lib.v2.rendering.projection package ports the 1.21.1 renderer contract to the existing native rendering module. It does not require OpenGL vertex-buffer calls or a second renderer module.
Populate a ProjectionScene with local block positions, optional block entities, and entities. Populate all neighbors before calling ProjectionRenderer.rebuild(scene, alpha); alpha is in [0, 255]. The scene preserves model data, shifted fluid neighbors and a customizable tint callback. Entities remain caller-owned and are never spawned or ticked by the renderer.
Render on the client render thread, supplying a camera-relative pose and CameraRenderState. The cached block mesh combines the current model-view matrix with that pose, matching the native entity buffer path. Movement requires only a new pose. Rebuild after scene/layer changes or whenever isValid() becomes false after resource reload. Call close() on replacement, world exit and permanent removal; repeated close is safe.
ProjectionFeatures provides native block-entity/entity submission for GUI previews too. Alpha 255 preserves the original render type. Call clear() to drop retained per-scene state without destroying its reusable native dispatcher, and close() when the owner is disposed. ProjectionRenderTypes.blocks() avoids applying entity diffuse lighting a second time to already shaded block/fluid quads.
Validation: module compileJava, jar, check, plus the paired Ageratum runStructureTest real-client fixture (33 checks covering cached rendering, layers, fluid neighbors, entities, movement, resource reload, replacement and cleanup). Ageratum contains repeatable 1.21.1 preview/projection captures. Custom resource packs, shader packs and other platforms were not validated in this node.