[1.7.10] Door questions

[Thornack]

Hi so I am looking into the door class's func_150012_g function which I have renamed to be called rotateDoor as it seems to impart this functionality I think.

I have been trying to understand how func_150012_g works and so far I seem to have found some bizarre behaviour. in particular

boolean flag = (doorMetadata &  != 0;

I used

System.out.println("doorMetadata variable equals:" + doorMetadata); 

right below the flag and I get a value between 1 and 8 inclusive printed to the console every tick it seems. Where this number seems to only be zero if the door isnt placed in the world. If I change the value of the 8 to something other than 8 the door halves arent aligned anymore. also at a value of 12 the door halves are once again aligned and at a value of 18 they are aligned but the top half is on the bottom and the bottom half is at the top. I am having a hard time figuring out exactly how this method works. Any helpful comments are appreciated.

 

This is the function I am writing based off of func_150012_g to impart custom functionality to door rotation and change how doors open. But I need to understand them first

public int rotateDoor(IBlockAccess blockAccess, int blockXCoord, int blockYCoord, int blockZCoord)
    {
        int doorMetadata = blockAccess.getBlockMetadata(blockXCoord, blockYCoord, blockZCoord);
        // for some reason the 8 has to be there otherwise the door halves arent aligned. 
        // It isnt intuitive either at a value of 12 they are aligned again and also at a value of 18 but not as they should be
        int offsetDoorHalvesToAlign = 8;
        System.out.println("____________________________________" + doorMetadata);
        boolean flag = (doorMetadata & offsetDoorHalvesToAlign) != 0;
        int i1;
        int j1;

        if (flag)
        {
            i1 = blockAccess.getBlockMetadata(blockXCoord, blockYCoord - 1, blockZCoord);
            j1 = doorMetadata;
        }
        else
        {
            i1 = doorMetadata;
            j1 = blockAccess.getBlockMetadata(blockXCoord, blockYCoord + 1, blockZCoord);
        }

        boolean flag1 = (j1 & 1) != 0;
        return i1 & 7 | (flag ? 8 : 0) | (flag1 ? 16 : 0);
    }

[Draco18s]

If I change the value of the 8 to something other than 8 the door halves arent aligned anymore.

 

No shit.

http://minecraft.gamepedia.com/Door#Block_data

[Thornack]

Im sorry Draco,

 

I am not a JAVA Wizard. I am still learning the ins and outs of the language I dont really understand your comment. (not that good yet) but I am still learning. Could you please elaborate

[Draco18s]

The link goes to the wiki page, which details what the door's metadata does.

In this case, the 4th bit ("8") means "this block is the top half of the door."