I just had a wonderful idea and was wondering if it would work. Is there a way to damage an item instead of destroying it when used as fuel in the furnace? Then you could have more fuel in one block without it going to waste. And also if it is possible how would you do it?

Make your fuel item damageable.

now i havtn actually tried this so correct me if im wrong, but surely making the item damageable doesn't make the furnace do it dmg instead of destroying it? surely you would have to find a method similar to onCrafting or make your own custom furnace to check for dmg before removing one from the fuel itemstack?

A wooden pickaxe in a Furnace gets used up straight away, it doesn't get damaged...

Then override getContainer(ItemStack) by returning the itemstack, damaged as you want it to.

I was thinking 'that can't work, Lava Buckets are container items and are used up too'. Tested it, and they didn't. I didn't know that. When did Mojang add that . It has been some while that I've used a Lava Bucket as fuel source.

 

Anyway, cool feature, and GotoLink's solution will work .