Minecraft模组开发：如何通过代码在指定World和BlockPos位置放置方块

核心逻辑 #

• 重写底部方块的放置触发方法，放置底部时自动检测上方可放置空间，生成对应上半部分方块
• 同步重写底部方块的移除触发方法，底部被破坏时同步销毁上方的上半部分方块，避免出现浮空残留

Forge 端实现代码 #

// 重写底部方块的onPlace方法
@Override
public void onPlace(BlockState state, Level level, BlockPos pos, BlockState oldState, boolean isMoving) {
    if (!level.isClientSide) {
        BlockPos upperPos = pos.above();
        if (level.getBlockState(upperPos).canBeReplaced()) {
            // 替换为你自己注册的上半部分方块实例
            level.setBlock(upperPos, YourModBlocks.UPPER_HALF_BLOCK.get().defaultBlockState(), 3);
        }
    }
    super.onPlace(state, level, pos, oldState, isMoving);
}

// 同步处理破坏逻辑
@Override
public void onRemove(BlockState state, Level level, BlockPos pos, BlockState newState, boolean isMoving) {
    if (!level.isClientSide) {
        BlockPos upperPos = pos.above();
        if (level.getBlockState(upperPos).is(YourModBlocks.UPPER_HALF_BLOCK.get())) {
            level.removeBlock(upperPos, false);
        }
    }
    super.onRemove(state, level, pos, newState, isMoving);
}

setBlock 第三个参数3为更新标记组合，代表同时向客户端同步更新、阻止多余重渲染，是方块放置场景的常用配置。

Fabric 端实现代码 #

@Override
public void onPlaced(World world, BlockPos pos, BlockState state, LivingEntity placer, ItemStack itemStack) {
    if (!world.isClient) {
        BlockPos upperPos = pos.up();
        if (world.getBlockState(upperPos).isReplaceable()) {
            // 替换为你自己注册的上半部分方块实例
            world.setBlockState(upperPos, YourModBlocks.UPPER_HALF_BLOCK.getDefaultState(), Block.NOTIFY_ALL);
        }
    }
    super.onPlaced(world, pos, state, placer, itemStack);
}

@Override
public void onStateReplaced(BlockState state, World world, BlockPos pos, BlockState newState, boolean moved) {
    if (!world.isClient) {
        BlockPos upperPos = pos.up();
        if (world.getBlockState(upperPos).isOf(YourModBlocks.UPPER_HALF_BLOCK)) {
            world.removeBlock(upperPos, false);
        }
    }
    super.onStateReplaced(state, world, pos, newState, moved);
}

上半部分阴影问题修复方案 #

• 方块属性注册时添加noOcclusion配置，关闭方块遮光判定，避免相邻方块投射阴影
• 方块模型JSON文件中添加配置 "ambientocclusion": false，关闭模型的环境光遮蔽计算，即可消除异常阴影

内容的提问来源于stack exchange，提问作者F4LS3