Let’s assume that we have these variables.
// base shipping cost of product $product_shipping_cost = 10; // You can send 4 same products in the same pack with $product_shipping_cost $product_shipping_interval_quantity = 4; // Your current quantity in cart $cart_quantity = 9; // defined total shipping cost, should be in this case 30; // because 9 in $cart quantity $total_shipping_cost = 0;
How should this work in real life? So basically we have this:
- When $cart_quantity == 1 then $total_shipping_cost is 10$
- When $cart_quantity <= 4 then $total_shipping_cost is still 10$
- When $cart_quantity == 5 then $total_shipping_cost should be 20$
- When $cart_quantity <= 8 then $total_shipping_cost is still 20$
- When $cart_quantity == 9 then $total_shipping_cost should be 30$
- and so on and so forth …
How to achieve such a formula? I tried to
$total_shipping_cost = $product_shipping_cost * floor($cart_quantity/$product_shipping_interval_quantity)
But it doesn’t work, it changing only when 4/8/12 etc not on 5/9/13 and it is not starting with 10 when ie: 2 pcs in cart.