Block Attributes
textureFileBack
This attribute defines texture file that the block will use for its back side. Texture files for this attribute go into the textures/blocks directory of your mod.
Examples
// Uses textures/blocks/myBlockBack.png from the mod's directory
textureFileBack[0] = "myBlockBack.png";
// Uses textures/blocks/wood.png from the minecraft.jar
textureFileBack[1] = "/wood.png";
// Uses mods/SomeMod/blocks/someBlock.png
textureFileBack[0] = "/SomeMod:someBlock.png";
textureFileBack[0] = "myBlockBack.png";
// Uses textures/blocks/wood.png from the minecraft.jar
textureFileBack[1] = "/wood.png";
// Uses mods/SomeMod/blocks/someBlock.png
textureFileBack[0] = "/SomeMod:someBlock.png";