Minecraft V1.19.1

// Add roof level.setBlock(new BlockPosition(pos.getX() + buildingSize / 2, pos.getY() + 1, pos.getZ() + buildingSize / 2), Blocks.STONE_SLAB.defaultBlockState(), 2); } } To register the feature, you can use the following code:

public CityStructure(Level level, BlockPosition pos) { this.level = level; this.pos = pos; } Minecraft v1.19.1

// CityFeatureRegistration.java package com.example.minecraft.feature; // Add roof level