The best-fit packing algorithm has been introduced to enable easier setup of the Dimensional Shipping extension. Its a slightly lower level of accuracy than the exact-packing algorithm but its much easier to setup.
Firstly you need to put the following attributes into your attribute set on your products (these are installed as part of the extension). Please ensure you add the following attributes to the Shipping subgroup in the relevant Attribute Sets:
Then setup up your boxes that can be used for your products.
In Shipping Settings switch algorithm to Best Fit Packing, and change the tolerance if required (it defaults to 20% allowing for space in the box).
On your products please enter the length, width, height, and assign the possible boxes that the product can fit in.
The algorithm will work out how much a box can hold based on volume, tolerance and whether it can physically fit (e.g. a 20inch length item cannot fit in a 10x5x5 box physically).
This data is then used to calculate the boxes to use across the cart and fill according to existing algorithms in the extension.
You do not have to enter dimensions for a product. If not entered it will assume that any number of the item can fit in the box (restricted only by max weight/qty on the box itself).
You can combine this with the multiple boxes for a SKU and ship separate capabilities.
You can combine best-fit products with exact-fit products, just select Best-Fit Packing in Shipping Settings and then where required assign your products to single boxes instead of the best-fit configuration