Block Attributes
textureFileSides
This attribute defines the texture file that the block will use for all sides except front and back. Texture files for this attribute go into the assets/{mod name}/textures/blocks directory of your mod.
Examples
// Uses assets/{mod name}/textures/blocks/myBlockSides.png from the mod's directory
textureFileSides[0] = "myBlockSides.png";
// Uses assets/minecraft/textures/blocks/wood.png from the minecraft.jar
textureFileSides[1] = "/wood.png";
// Uses assets/SomeMod/textures/blocks/someBlock.png
textureFileSides[0] = "/SomeMod:someBlock.png";
textureFileSides[0] = "myBlockSides.png";
// Uses assets/minecraft/textures/blocks/wood.png from the minecraft.jar
textureFileSides[1] = "/wood.png";
// Uses assets/SomeMod/textures/blocks/someBlock.png
textureFileSides[0] = "/SomeMod:someBlock.png";