Render negative-Y sections on 1.18+ worlds - #488
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A camera below y=0 renders nothing but the clear color: a bot standing on the surface of any 1.18+ world (surface ~y=-60 in the overworld's lower range, or anywhere in a deepslate cave) shows a uniform sky-blue frame with the surrounding chunks fully loaded. Three spots hardcode the pre-1.18 world range [0, 256): - worldrenderer.js dirty-section loops in addColumn/removeColumn iterate y=0..240, so sections below y=0 are never queued for meshing - worker.js indexes chunk.sections[floor(y/16)], but 1.18+ ChunkColumn indexes from minY (-64): sections[(y - minY) >> 4]; y<0 resolves to sections[-1] = undefined and the section is skipped - models.js culls faces against a hardcoded y<0 instead of the world's minY Derive minY/worldHeight from the version's chunk implementation (defaults 0/256, so pre-1.18 is unchanged), iterate the real range, index worker sections by (y - minY)/16, and gate models.js culling on world.minY. Revives PrismarineJS#485 (closed); no longer stacked on the 26.1 PR.
…enderer Requiring prismarine-chunk from worldrenderer.js pulled all of minecraft-data into the browser index bundle, OOMing webpack in CI. The node-side loadChunk producers already have the column, so they send minY/worldHeight along with the chunk.
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Revives #485 as a standalone change (the original was stacked on #484; this one is based on master and depends on nothing else).
Problem
A camera below y=0 renders nothing but the clear color — a mineflayer bot standing on the surface of any 1.18+ overworld, or anywhere in a deepslate cave, shows a uniform sky-blue frame even with the surrounding chunks fully loaded.
Cause
Three spots hardcode the pre-1.18 world range [0, 256):
worldrenderer.jsdirty-section loops inaddColumn/removeColumniteratey = 0..240, so sections below y=0 are never queued for meshing.worker.jsindexeschunk.sections[Math.floor(y / 16)], but 1.18+ChunkColumnindexes fromminY(-64):sections[(pos.y - minY) >> 4]. For y<0 this resolves tosections[-1]= undefined and the section is skipped.models.jsculls faces against a hardcodedy < 0instead of the world'sminY, so every face on a below-zero surface is culled.Fix
minY/worldHeightfrom the version's chunk implementation insetVersion(defaults0/256, so pre-1.18 behavior is unchanged) and iterate the real range.(y - (chunk.minY ?? 0)) / 16.minYon the worker'sWorldwrapper and gatemodels.jsculling onworld.minY ?? 0.Verification
Confirmed live: a mineflayer bot on a Paper 1.21.8 server standing at y=-60 rendered a blank sky before and a full grass-plains first-person view after (headless-gl + this branch).
setVersion('1.16.5')/'1.12.2'still resolve to{ minY: 0, worldHeight: 256 }, so pre-1.18 is untouched.