So my mod adds Ice slabs and stairs. In 1.6, my slabs and stairs worked just fine. But in 1.7.2, due to the rendering changes, I can see normal Ice, as well as other instances of my ice slabs/stairs through my slabs and stairs. I fixed this with this code:

	    @SideOnly(Side.CLIENT)
    public boolean shouldSideBeRendered(IBlockAccess blockAccess, int X, int Y, int Z, int side)
    {
    	Block block = blockAccess.getBlock(X, Y, Z);
        return !(block==this)&&this.modelBlock.shouldSideBeRendered(blockAccess, X, Y, Z, side);
    }

 

It works, but It also messes up the non-full block parts of the slabs and stairs.

 

http://i59.tinypic.com/2vj5wyh.png

 

I also can still see my slabs through my stairs, and visa-versa.

 

I tried using a function that checked if it was any one of my ice blocks, or ice itself, and that worked, but I still had the invisible stair section problem. The corner of the bricks next to the stairs also would be invisible with that method. Lastly, you could still see vanilla Ice through my Ice.

 

I am wondering what would be the best way to fix this, obviously I am going to probably have to do custom rendering, but how should I go about that?

shouldSideBeRendered() is only useful for solid blocks. You'll have to use your own rendering code for stairs and slabs.