Crash: NeoForgeSlopeBakedModel.getQuads NPEs on null frame sprite when called with empty ModelData (e.g. by Xaero's World Map)

[CN-YiMin]

Version

• Automobility: 0.5.0.h+1.21.1-neoforge
• Minecraft: 1.21.1 / NeoForge 21.1.235
• Triggering mod: Xaero's World Map 1.43.0 (via xaerolib 1.6.0)

Description

NeoForgeSlopeBakedModel.getQuads(...) resolves the frame sprite from
data.get(FRAME_SPRITE). FRAME_SPRITE is only ever populated in
getModelData(). When another mod calls getQuads with an empty/underived
ModelData (Xaero's World Map does this to compute block translucency while
caching map chunks), data.get(FRAME_SPRITE) returns null. That null sprite
is passed into buildSlopeGeometry → rightTriPrism →
NeoForgeGeometryBuilder.vertex, which calls sprite.getU0() and throws NPE.

Stack trace (abridged)

Caused by: java.lang.NullPointerException: Cannot invoke
"net.minecraft.client.renderer.texture.TextureAtlasSprite.getU0()" because "sprite" is null
at automobility/...NeoForgeGeometryBuilder.vertex(NeoForgeGeometryBuilder.java:56)
at automobility/...SlopeBakedModel.rightTriPrism(SlopeBakedModel.java:143)
at automobility/...SlopeBakedModel.buildSlopeGeometry(SlopeBakedModel.java:83)
at automobility/...NeoForgeSlopeBakedModel.getQuads(NeoForgeSlopeBakedModel.java:83)
at xaerolib/...NeoForgeBlockModelUtils.getQuads(NeoForgeBlockModelUtils.java:39)
at xaerolib/...BlockTranslucencyUtils.getModelBasedTranslucency(...)
at xaeroworldmap/...MapWriter.shouldOverlay(MapWriter.java:642)
... (Xaero's World Map chunk writer)

Steps to reproduce

1. Install Automobility + Xaero's World Map on NeoForge 1.21.1.
2. Place any Automobility slope block in the world.
3. Have the world map cache/render a chunk containing that slope block.
   → Client crashes with the NPE above.

Suggested fix

Guard against a missing frame sprite in NeoForgeSlopeBakedModel.getQuads
(and/or null-check sprite in NeoForgeGeometryBuilder.vertex), e.g. return
Collections.emptyList() when data.get(FRAME_SPRITE) == null, since a caller
without proper ModelData cannot provide the sprite anyway.