[1.8.9] Generate biome terrain beneath the surface

[blahblahbal]

I've been working on a biome in which the stone beneath the surface (to a point) is replaced with a variant. The code I have now works to a degree, but this is what happens when it generates a cave:

 

I'm pretty sure I know why this happens (the vanilla gen doesn't recognize the variant and thus does not replace it with air), but what I don't know is how to fix it. Here is the code:

 

public void generateBiomeTerrain2(World worldIn, Random rand, ChunkPrimer chunkPrimerIn, int p_180628_4_, int p_180628_5_, double p_180628_6_)
    {
        int i = 63;
        IBlockState iblockstate = this.topBlock;
        IBlockState iblockstate1 = this.fillerBlock;
        IBlockState seashell = ModBlocks.seashell.getDefaultState();
        int rn2 = rand.nextInt(4);
        if (rn2 == 0)
        	seashell = ModBlocks.seashell.getDefaultState().withProperty(FACING, EnumFacing.EAST);
        else if (rn2 == 1)
        	seashell = ModBlocks.seashell.getDefaultState().withProperty(FACING, EnumFacing.WEST);
        else if (rn2 == 2)
        	seashell = ModBlocks.seashell.getDefaultState().withProperty(FACING, EnumFacing.SOUTH);
        else if (rn2 == 3)
        	seashell = ModBlocks.seashell.getDefaultState().withProperty(FACING, EnumFacing.NORTH);
        IBlockState l_seashell = ModBlocks.largeSeashell.getDefaultState();
        int rn = rand.nextInt(4);
        if (rn == 0)
        	l_seashell = ModBlocks.largeSeashell.getDefaultState().withProperty(FACING, EnumFacing.EAST);
        else if (rn == 1)
        	l_seashell = ModBlocks.largeSeashell.getDefaultState().withProperty(FACING, EnumFacing.WEST);
        else if (rn == 2)
        	l_seashell = ModBlocks.largeSeashell.getDefaultState().withProperty(FACING, EnumFacing.SOUTH);
        else if (rn == 3)
        	l_seashell = ModBlocks.largeSeashell.getDefaultState().withProperty(FACING, EnumFacing.NORTH);
        int j = -1;
        int k = (int)(p_180628_6_ / 3.0D + 3.0D + rand.nextDouble() * 0.25D);
        int l = p_180628_4_ & 15;
        int i1 = p_180628_5_ & 15;

        for (int ypos = 255; ypos >= 0; --ypos)
        {
            if (ypos <= rand.nextInt(5))
            {
                chunkPrimerIn.setBlockState(i1, ypos, l, Blocks.bedrock.getDefaultState());
            }
            else
            {
                IBlockState iblockstate2 = chunkPrimerIn.getBlockState(i1, ypos, l);

                if (iblockstate2.getBlock().getMaterial() == Material.air)
                {
                    j = -1;
                }
                else if (iblockstate2.getBlock() == Blocks.stone)
                {
                    if (ypos >= 32 - rand.nextInt(7))
                    {
                    	chunkPrimerIn.setBlockState(i1, ypos, l, ModBlocks.tropicStone.getDefaultState());
                    }
                    if (j == -1)
                    {
                    	if (k <= 0)
                    	{
                    		iblockstate = null;
                    		iblockstate1 = ModBlocks.blackSand.getDefaultState();
                    	}
                    	else if (ypos >= i - 4 && ypos <= i + 1)
                    	{
                    		iblockstate = ModBlocks.blackSand.getDefaultState();
                    		iblockstate1 = ModBlocks.blackSand.getDefaultState();
                    	}
                        j = k;
                        if (ypos >= i - 1)
                        {
                        	if (rand.nextInt(40) == 0 && chunkPrimerIn.getBlockState(i1, ypos + 1, l).getBlock().getMaterial() == Material.air)
                        	{
                        		if (rand.nextInt(35) == 0) chunkPrimerIn.setBlockState(i1, ypos + 1, l, l_seashell);
                        		else chunkPrimerIn.setBlockState(i1, ypos + 1, l, seashell);
                        	}
                        	chunkPrimerIn.setBlockState(i1, ypos, l, ModBlocks.blackSand.getDefaultState());
                        }
                        else if (ypos < i - 1 && ypos >= i - 7 - k)
                        {
                        	iblockstate = null;
                        	iblockstate1 = ModBlocks.tropicStone.getDefaultState();
                        }
                        else if (ypos < i - 7 - k)
                        {
                            iblockstate = null;
                            iblockstate1 = ModBlocks.tropicStone.getDefaultState();
                            chunkPrimerIn.setBlockState(i1, ypos, l, Blocks.gravel.getDefaultState());
                        }
                        else
                        {
                            chunkPrimerIn.setBlockState(i1, ypos, l, iblockstate1);
                        }
                    }
                    else if (j > 0)
                    {
                        --j;
                        chunkPrimerIn.setBlockState(i1, ypos, l, iblockstate1);

                        if (j == 0 && iblockstate1.getBlock() == ModBlocks.blackSand)
                        {
                            j = rand.nextInt(4) + Math.max(0, ypos - 63);
                            iblockstate1 = ModBlocks.blackSandstone.getDefaultState();
                        }
                        /*if (j == 0 && iblockstate1.getBlock() == Blocks.stone)
                        {
                        	//j = rand.nextInt(4) + Math.max(0, ypos - 63);
                        	int rn3 = 7 + rand.nextInt(15) 
                        	if (ypos >= rn3)
                        	chunkPrimerIn.setBlockState(i1, ypos, l, ModBlocks.tropicStone.getDefaultState());
                        }*/
                    }
                }
            }
        }
    }

 

I don't think there needs to be any more code shown, but if I'm wrong, let me know.

[jeffryfisher]

Cave creation seems to work around all manner of custom ores, so you might be able to do your stone variant as a kind of "ore" generation that is restricted by biome. NB: If you generate large amounts of this stuff, just be careful that it doesn't overflow its chunk boundaries (contributing to runaway terrain-gen).

 

BTW,  Do you get vanilla coal and iron ore bodies forming in your variant stone? Do you want them? By delaying your replacement until ore-generation, you might also control vanilla ores.

[blahblahbal]

I actually don't get vanilla coal and iron in the stone. I 'fixed' this by creating a variant of coal and iron ore that only generates in the variant stone.

 

I thought about using the ore generator to replace the stone, but then the problem is getting the borders, like you said. I guess it wouldn't be too problematic if it extended partially outside the biome. I'll try this way of generating the stone.