chevyray / crunch-rs Goto Github PK

Would it be possible to somehow remove the T: Clone restriction for items? I would think that this should improve performance (especially if the T has some complex data), and possibly streamline the code itself?

It might be possible to do with if the PackedItem<T> would hold references to T, using Packer for lifetime. Another option (but i'm not certain it will work), is for fn pack() to take the ownership of the self.items_to_pack (replacing it with an empty vec), but that seem to conflict with fn pack_into_po2() which can call pack() multiple times. Lastly, perhaps the packed structure could just store a vector of usize, referencing the indexes of self.items_to_pack.

One thing to note - I believe it would be possible to optimize this only if all public API would become consuming, e.g. pack(self, ...) instead of pack(&mut self, ...) (and same for pack_into_po2)

Stuff you probably already know

Algorithms that pack arbitrary shapes are useful for a variety of applications. For example, a manufacturer can pack parts to be cut from a sheet of material so as to minimize the amount of material wasted. In the most general setting the problem has no known solution. Particular cases, like the one this crate solves, can be shown to be NP-complete. But as with many NP-complete problems, there are approximating algorithms that do pretty well in practice.

Arbitrary shapes

It would be nice to have a crate that can pack arbitrary shapes. Such a crate, if it were generic, would have many potential uses.

Most types benefit from a Debug implementation, and it looks like only Rect supports it in this crate right now.

Specifically, the lack of the Debug trait for PackedItem means that you can't .unwrap() or .expect() the result of Packer::pack.

I think you should be able to add #[derive(Debug)] to all of {Item, PackedItem, PackedItems, Packer, and Rotation}. It looks like maybe you were avoiding it on the generic types but the derive macro should handle the generic type correctly for this crate's purposes.

I can't figure out how to add images to atlas