Slabbed — Changelog

0.4.0-beta (changes since 0.3.0)

Builds in this release

• slabbed-1.21.11-0.4.0-beta.4.jar — Minecraft 1.21.11
• slabbed-1.21.1-0.4.0-beta.3.jar — Minecraft 1.21.1

0.4.0-beta is a large step up from 0.3.0: a ground-up overhaul of the Terrain Slabs compatibility layer, plus a long list of positioning, rendering, and stability fixes — including several found and confirmed during live play-testing. The 1.21.11 build carries the newest fixes (-beta.4); the 1.21.1 build (-beta.3) shares the same core behavior.

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Terrain Slabs compatibility — overhaul

• Objects sit correctly on Terrain Slabs surfaces, exactly as they do on vanilla slabs: torches, lanterns, fences, walls, glass panes, signs, chests / hoppers / furnaces and other block-entities, the crafting table, and a curated set of decorative full cubes (pumpkin, carved pumpkin, jack o'lantern, melon, bookshelf, hay bale, note block, dried kelp block, sponge/wet sponge, target, redstone lamp, smithing/fletching/cartography tables, loom).
• Full range of Terrain Slabs surfaces recognized (named/extended support surfaces), and works with both the modern terrain_slabs and the legacy terrainslabs mod id.
• Natural terrain stays put. Plain opaque world cubes (stone, dirt, grass block, sand, ore, …) are no longer lowered onto Terrain Slabs surfaces — what keeps natural terrain hole-free.
• Stacking on slabs: objects stack correctly over a slab (a torch on a fence, a fence on a fence, …).
• Connections respect height steps: fences, walls, and panes no longer connect across a Slabbed height step, and stay as single posts down a slab.

Vegetation — FIXED (new in -beta.4, 1.21.11)

• Short grass, ferns, and tall grass no longer render invisible or sunk on Terrain Slabs terrain. They now sit correctly on the slab surface. (Root cause: Slabbed and Terrain Slabs were each offsetting the same plant model, double-lowering it out of sight — fixed so Terrain Slabs owns the vegetation offset and Slabbed does not add a second.)

Decorations & hangers

• Hanging roots, spore blossom, and hanging signs hang flush under a slab — no gap — and no longer pop up when a neighboring block is broken.
• Hanging lanterns hang flush under a flush slab (previously dropped with a visible gap). (new in -beta.4)
• Decorative hangers follow a lowered support block down instead of clipping into it.

Stacks & compound (mixed) slabs

• Vertical compound stacks sit flush. A slab / block / slab / block tower no longer leaves the top block floating half a block above the slab — it compounds to sit flush. (new in -beta.4)
• Mixed slabs (a vanilla slab capping a Terrain Slabs surface) compound to the full lowered height, and objects resting on them follow down with them.
• An object on a vanilla top slab capping a Terrain Slabs slab now sits flush instead of floating.

"Never pop" placement law

• A block you place stays exactly where you put it. Slabbed no longer recomputes a placed block's height on the fly, so adding or removing a neighboring slab can no longer make a placed block autonomously pop up or down. Note: build support-first — a block placed in mid-air will not retroactively drop when you add support under it later; place it on its support (or break and replace).

Rendering

• Fence, wall, and glass-pane posts sit flush on vanilla slabs (GitHub #21). Previously the post's model floated at full height while its outline/selection box lowered correctly — so the post appeared to hover above its own hitbox on a vanilla slab (it already worked on Terrain Slabs surfaces). The model now renders at the same lowered position as its outline on every slab, and connection arms still break correctly across a height step. (new in -beta.4)
• Ghost-window / see-through seams on lowered cubes are gone — the exposed step faces between a lowered block and a flush neighbor render solid now, across vanilla, compound, and cantilever lowering, on both the Sodium and the vanilla render paths.
• World-hole "DODO" fixed — natural Terrain Slabs terrain no longer tears see-through holes (the bug that pulled the previous 0.4.0-beta.3). The terrain-flush test is now view-independent, so it can't disagree between the render thread and the main thread.
• Powder snow stays flush on and beside Terrain Slabs terrain (no half-block step across snowy ground).

Targeting & interaction

• Lowered chests, torches, and beds target correctly — the outline/selection box and the raycast align with where the block is actually drawn.
• Slabs place correctly against lowered slab and lowered full-block faces.

Dev / debug

• /slabdy in-game overlay shows the targeted block's computed vertical offset and its source (vanilla vs Terrain Slabs) — for diagnosing positioning.

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Stability / under the hood

• Headless game-test suite expanded substantially (compound, cull, freeze, hanger, vegetation, powder-snow, terrain-hole, fence-connection, and adversarial-regression guards) — 46 server tests green on the 1.21.11 build.
• Render-region boundary lookups guarded against world-load crashes.
• Release jars exclude dev/debug entrypoints, and all remaining diagnostic logging is gated off by default (a pre-release hygiene pass stripped the last always-on debug traces).

Compatibility: Minecraft 1.21.11 (Fabric) with Countered's Terrain Slabs; a separate Minecraft 1.21.1 build is included. Slabbed is inert when Terrain Slabs is not installed (vanilla slab behavior only).