Latitude 1.5.1 Beta 3 — Minecraft 1.21.11

This brings the 1.21.11 line level with the 26.2 line, plus the fixes found in live testing afterwards.

New

• Other World Types & Datapacks… — a new option on Latitude's create-world screen that opens Minecraft's full setup, so Superflat, datapacks, and other mods' world types are reachable from inside Latitude. Your world name and seed carry across.
• Desert riverbanks can be green. Where an arid biome meets fresh water, the bank sometimes grows grass and wildflowers instead of running bare sand to the waterline.

Improved

• Badlands is no longer a seed lottery. The noise deciding where mesa country sits scaled with world size, so one unlucky roll could hand most of the dry belt to badlands. Measured across twelve seeds it covered 24%–71% of the dry belt; it now covers 11%–30%, in many more, smaller regions.
• Green riverbanks read as banks, not speckle. They now hug the waterline, form longer and rarer verdant reaches, and fade smoothly with distance from water instead of ending at a hard rim.
• Ctrl+Tab cycles the tabbed create-world panels, and switching panels no longer leaves keyboard focus on a hidden control.

Fixed

• Creating a world no longer crashes. Latitude picks your start point by testing candidate spots in your chosen climate zone; when none passed, it failed at the Create World screen. Measured across 240 fresh worlds this hit 41 of them — about one in six, worst in Polar. An exhausted search now hands off to Minecraft's own safe-spawn placement instead of failing.
• Far-polar terrain no longer shows degraded husks of tree-bearing biomes from other worldgen mods, or their decorations left floating in mid-air. Latitude's polar ecology now recognizes treed biomes by what they actually plant rather than by their names, and stripped vegetation can no longer strand what was growing on it.
• Fresh worlds now nearly always reserve their swamp province. The reservation asked for conditions to hold across a 224-block span in four directions at once, which swamp's patchy ground rarely manages; it failed on roughly a quarter of worlds. It now asks for a span that fits, and fails on roughly one world in forty. Ordinary swamp generation was never affected — swamps were never missing, only the reservation.
• Shallow coastlines no longer receive deep-ocean identities. Outside the tropics, ocean identity was rolled by map noise regardless of actual depth; every band now respects true depth.
• Temperate forests no longer cross into the true desert belt. Soft band boundaries could promote spots deep inside the 23.5°–35° dry belt into the temperate pool, planting lush forest islands in open desert.
• Unrecognized modded beaches stay beaches, rather than being rerouted into inland biomes or bypassing swamp and mangrove placement rules.
• Loading the Nether can no longer briefly disarm world generation. An ordering quirk let the Nether's load step clear Latitude's overworld authority for a moment; chunks generated in that window silently fell back to vanilla.
• Each climate zone spawns you at the middle of its own band, with a regression test pinning it.

Known limitation

The reserved-biome system can still miss. Across forty fresh worlds on this build, three lost a reserved biome — one swamp, two in the mountain/windswept family. This is pre-existing, is not caused by these fixes, and is not specific to any one biome: the underlying check is too strict and can hit whichever biome is unlucky on a given seed.

The biomes themselves still generate normally. Only the reservation guarantee fails, and the symptom is messages in the log rather than anything missing in play. A better test is planned.

World-generation changes apply to newly generated terrain.