Chisel/src/main/java/com/cricketcraft/chisel/client/render/CTM.java

package com.cricketcraft.chisel.client.render;

import net.minecraft.block.Block;
import net.minecraft.world.IBlockAccess;
import net.minecraftforge.common.util.ForgeDirection;

import com.cricketcraft.chisel.api.IFacade;

public class CTM {

	static int submaps[][] = { { 16, 17, 18, 19 }, { 16, 9, 18, 13 }, { 8, 9, 12, 13 }, { 8, 17, 12, 19 }, { 16, 9, 6, 15 }, { 8, 17, 14, 7 }, { 2, 11, 6, 15 }, { 8, 9, 14, 15 }, { 10, 1, 14, 15 },
			{ 10, 11, 14, 5 }, { 0, 11, 4, 15 }, { 0, 1, 14, 15 }, {}, {}, {}, {}, { 16, 17, 6, 7 }, { 16, 9, 6, 5 }, { 8, 9, 4, 5 }, { 8, 17, 4, 7 }, { 2, 11, 18, 13 }, { 10, 3, 12, 19 },
			{ 10, 11, 12, 13 }, { 10, 3, 14, 7 }, { 0, 11, 14, 15 }, { 10, 11, 4, 15 }, { 10, 11, 4, 5 }, { 10, 1, 14, 5 }, {}, {}, {}, {}, { 2, 3, 6, 7 }, { 2, 1, 6, 5 }, { 0, 1, 4, 5 },
			{ 0, 3, 4, 7 }, { 2, 11, 6, 5 }, { 8, 9, 4, 15 }, { 2, 1, 6, 15 }, { 8, 9, 14, 5 }, { 0, 1, 4, 15 }, { 0, 1, 14, 5 }, { 10, 1, 4, 15 }, { 0, 11, 14, 5 }, {}, {}, {}, {}, { 2, 3, 18, 19 },
			{ 2, 1, 18, 13 }, { 0, 1, 12, 13 }, { 0, 3, 12, 19 }, { 10, 1, 12, 13 }, { 0, 3, 14, 7 }, { 0, 11, 12, 13 }, { 10, 3, 4, 7 }, { 0, 11, 4, 5 }, { 10, 1, 4, 5 }, { 10, 11, 14, 15 },
			{ 0, 1, 4, 5 }, {}, {}, {}, {}, };

	public static int[] getSubmapIndices(IBlockAccess world, int x, int y, int z, int side) {
		int index = getTexture(world, x, y, z, side);

		return submaps[index];
	}

	public static int getTexture(IBlockAccess world, int x, int y, int z, int side) {
		if (world == null)
			return 0;

		int texture = 0;
		Block block = world.getBlock(x, y, z);
		int blockMetadata = world.getBlockMetadata(x, y, z);

		boolean b[] = new boolean[6];
		if (side <= 1) {
			b[0] = isConnected(world, x - 1, y, z, side, block, blockMetadata);
			b[1] = isConnected(world, x + 1, y, z, side, block, blockMetadata);
			b[2] = isConnected(world, x, y, z + 1, side, block, blockMetadata);
			b[3] = isConnected(world, x, y, z - 1, side, block, blockMetadata);
		} else if (side == 2) {
			b[0] = isConnected(world, x + 1, y, z, side, block, blockMetadata);
			b[1] = isConnected(world, x - 1, y, z, side, block, blockMetadata);
			b[2] = isConnected(world, x, y - 1, z, side, block, blockMetadata);
			b[3] = isConnected(world, x, y + 1, z, side, block, blockMetadata);
		} else if (side == 3) {
			b[0] = isConnected(world, x - 1, y, z, side, block, blockMetadata);
			b[1] = isConnected(world, x + 1, y, z, side, block, blockMetadata);
			b[2] = isConnected(world, x, y - 1, z, side, block, blockMetadata);
			b[3] = isConnected(world, x, y + 1, z, side, block, blockMetadata);
		} else if (side == 4) {
			b[0] = isConnected(world, x, y, z - 1, side, block, blockMetadata);
			b[1] = isConnected(world, x, y, z + 1, side, block, blockMetadata);
			b[2] = isConnected(world, x, y - 1, z, side, block, blockMetadata);
			b[3] = isConnected(world, x, y + 1, z, side, block, blockMetadata);
		} else if (side == 5) {
			b[0] = isConnected(world, x, y, z + 1, side, block, blockMetadata);
			b[1] = isConnected(world, x, y, z - 1, side, block, blockMetadata);
			b[2] = isConnected(world, x, y - 1, z, side, block, blockMetadata);
			b[3] = isConnected(world, x, y + 1, z, side, block, blockMetadata);
		}
		if (b[0] & !b[1] & !b[2] & !b[3])
			texture = 3;
		else if (!b[0] & b[1] & !b[2] & !b[3])
			texture = 1;
		else if (!b[0] & !b[1] & b[2] & !b[3])
			texture = 16;
		else if (!b[0] & !b[1] & !b[2] & b[3])
			texture = 48;
		else if (b[0] & b[1] & !b[2] & !b[3])
			texture = 2;
		else if (!b[0] & !b[1] & b[2] & b[3])
			texture = 32;
		else if (b[0] & !b[1] & b[2] & !b[3])
			texture = 19;
		else if (b[0] & !b[1] & !b[2] & b[3])
			texture = 51;
		else if (!b[0] & b[1] & b[2] & !b[3])
			texture = 17;
		else if (!b[0] & b[1] & !b[2] & b[3])
			texture = 49;
		else if (!b[0] & b[1] & b[2] & b[3])
			texture = 33;
		else if (b[0] & !b[1] & b[2] & b[3])
			texture = 35;
		else if (b[0] & b[1] & !b[2] & b[3])
			texture = 50;
		else if (b[0] & b[1] & b[2] & !b[3])
			texture = 18;
		else if (b[0] & b[1] & b[2] & b[3])
			texture = 34;

		boolean b2[] = new boolean[6];
		if (side <= 1) {
			b2[0] = !isConnected(world, x + 1, y, z + 1, side, block, blockMetadata);
			b2[1] = !isConnected(world, x - 1, y, z + 1, side, block, blockMetadata);
			b2[2] = !isConnected(world, x + 1, y, z - 1, side, block, blockMetadata);
			b2[3] = !isConnected(world, x - 1, y, z - 1, side, block, blockMetadata);
		} else if (side == 2) {
			b2[0] = !isConnected(world, x - 1, y - 1, z, side, block, blockMetadata);
			b2[1] = !isConnected(world, x + 1, y - 1, z, side, block, blockMetadata);
			b2[2] = !isConnected(world, x - 1, y + 1, z, side, block, blockMetadata);
			b2[3] = !isConnected(world, x + 1, y + 1, z, side, block, blockMetadata);
		} else if (side == 3) {
			b2[0] = !isConnected(world, x + 1, y - 1, z, side, block, blockMetadata);
			b2[1] = !isConnected(world, x - 1, y - 1, z, side, block, blockMetadata);
			b2[2] = !isConnected(world, x + 1, y + 1, z, side, block, blockMetadata);
			b2[3] = !isConnected(world, x - 1, y + 1, z, side, block, blockMetadata);
		} else if (side == 4) {
			b2[0] = !isConnected(world, x, y - 1, z + 1, side, block, blockMetadata);
			b2[1] = !isConnected(world, x, y - 1, z - 1, side, block, blockMetadata);
			b2[2] = !isConnected(world, x, y + 1, z + 1, side, block, blockMetadata);
			b2[3] = !isConnected(world, x, y + 1, z - 1, side, block, blockMetadata);
		} else if (side == 5) {
			b2[0] = !isConnected(world, x, y - 1, z - 1, side, block, blockMetadata);
			b2[1] = !isConnected(world, x, y - 1, z + 1, side, block, blockMetadata);
			b2[2] = !isConnected(world, x, y + 1, z - 1, side, block, blockMetadata);
			b2[3] = !isConnected(world, x, y + 1, z + 1, side, block, blockMetadata);
		}

		if (texture == 17 && b2[0])
			texture = 4;
		if (texture == 19 && b2[1])
			texture = 5;
		if (texture == 49 && b2[2])
			texture = 20;
		if (texture == 51 && b2[3])
			texture = 21;

		if (texture == 18 && b2[0] && b2[1])
			texture = 7;
		if (texture == 33 && b2[0] && b2[2])
			texture = 6;
		if (texture == 35 && b2[3] && b2[1])
			texture = 23;
		if (texture == 50 && b2[3] && b2[2])
			texture = 22;

		if (texture == 18 && !b2[0] && b2[1])
			texture = 39;
		if (texture == 33 && b2[0] && !b2[2])
			texture = 38;
		if (texture == 35 && !b2[3] && b2[1])
			texture = 53;
		if (texture == 50 && b2[3] && !b2[2])
			texture = 52;

		if (texture == 18 && b2[0] && !b2[1])
			texture = 37;
		if (texture == 33 && !b2[0] && b2[2])
			texture = 36;
		if (texture == 35 && b2[3] && !b2[1])
			texture = 55;
		if (texture == 50 && !b2[3] && b2[2])
			texture = 54;

		if (texture == 34 && b2[0] && b2[1] && b2[2] && b2[3])
			texture = 58;

		if (texture == 34 && !b2[0] && b2[1] && b2[2] && b2[3])
			texture = 9;
		if (texture == 34 && b2[0] && !b2[1] && b2[2] && b2[3])
			texture = 25;
		if (texture == 34 && b2[0] && b2[1] && !b2[2] && b2[3])
			texture = 8;
		if (texture == 34 && b2[0] && b2[1] && b2[2] && !b2[3])
			texture = 24;

		if (texture == 34 && b2[0] && b2[1] && !b2[2] && !b2[3])
			texture = 11;
		if (texture == 34 && !b2[0] && !b2[1] && b2[2] && b2[3])
			texture = 26;
		if (texture == 34 && !b2[0] && b2[1] && !b2[2] && b2[3])
			texture = 27;
		if (texture == 34 && b2[0] && !b2[1] && b2[2] && !b2[3])
			texture = 10;

		if (texture == 34 && b2[0] && !b2[1] && !b2[2] && b2[3])
			texture = 42;
		if (texture == 34 && !b2[0] && b2[1] && b2[2] && !b2[3])
			texture = 43;

		if (texture == 34 && b2[0] && !b2[1] && !b2[2] && !b2[3])
			texture = 40;
		if (texture == 34 && !b2[0] && b2[1] && !b2[2] && !b2[3])
			texture = 41;
		if (texture == 34 && !b2[0] && !b2[1] && b2[2] && !b2[3])
			texture = 56;
		if (texture == 34 && !b2[0] && !b2[1] && !b2[2] && b2[3])
			texture = 57;
		return texture;
	}

	public static boolean isConnected(IBlockAccess world, int x, int y, int z, int side, Block block, int meta) {

		ForgeDirection dir = ForgeDirection.VALID_DIRECTIONS[side];

		int x2 = x + dir.offsetX;
		int y2 = y + dir.offsetY;
		int z2 = z + dir.offsetZ;
		
		Block con = getBlockOrFacade(world, x, y, z, side);
		Block obscuring = getBlockOrFacade(world, x2, y2, z2, side);
		
		// no block or a bad API user
		if (con == null) {
			return false;
		}
		
		boolean ret = con.equals(block) && getBlockOrFacadeMetadata(world, x, y, z, side) == meta;
		
		// no block obscuring this face
		if (obscuring == null) {
			return true;
		}
		
		// check that we aren't already connected outwards from this side
		ret &= !(obscuring.equals(block) && getBlockOrFacadeMetadata(world, x2, y2, z2, side) == meta);
		
		return ret;
	}

	public static int getBlockOrFacadeMetadata(IBlockAccess world, int x, int y, int z, int side) {
		Block blk = world.getBlock(x, y, z);
		if (blk instanceof IFacade) {
			return ((IFacade) blk).getFacadeMetadata(world, x, y, z, side);
		}
		return world.getBlockMetadata(x, y, z);
	}

	public static Block getBlockOrFacade(IBlockAccess world, int x, int y, int z, int side) {
		Block blk = world.getBlock(x, y, z);
		if (blk instanceof IFacade) {
			blk = ((IFacade) blk).getFacade(world, x, y, z, side);
		}
		return blk;
	}

}