Furnace entities can't be loaded with more than 1 stack of input materials

[shanemadden]

Assemblers, chemical plants, etc's input slots can accept more items than the stack size limit of the item in question, allowing 2 crafts worth of an item in their input slots despite the item potentially having a lower stack size.

The same is not true for furnace entities - because they don't determine a recipe until the ingredients are present, they don't accept any more than 1 full stack worth of an item in their source_inventory slot - it won't ever accept past 1 full stack of the source ingredient.

For performance reasons it's likely not possible to allow a multiple of the recipe input since the recipe isn't predetermined, but maybe it could be possible to specifically allow an over-stack in a furnace entity's input by allowing a source_inventory_size of greater than 1?

[Gergely]

Why wouldn't it be possible to allow a multiple of the recipe input? If the recipe used is determined by the item, there can only be one recipe for each item

This means that there is always a concrete answer to "How many do I need from this item to do the recipe twice?" Just check the recipe linked to that item.

[shanemadden]

I'm not sure when it happened but I just tested again, this limitation no longer appears to be present on furnaces in current 0.17. This can be moved to implemented, thanks!