I'm attempting to add the ability to make vehicle lists have an option to group by shared orders (https://www.tt-forums.net/viewtopic.php?f=32&t=84587
), but I've run into an issue there.
In the current master branch, the list of vehicles is backed by a GUIList<const Vehicle*>, and GUIList<T> inherits from SmallVector<T, 32>. In order to implement the ability to group by shared orders, each element in the GUIList can on longer be a single vehicle. Instead, each element should be a list of vehicles (and this list can be arbitrarily long, depending on the number of vehicles sharing the same orders).
Thus comes the problem: SmallVector (unlike std::vector) does not call constructors or destructors of its elements. This means that if I have a GUIList<std::vector<const Vehicle*>> (or any other type that does dynamic memory allocation), it would leak memory because the destruction of GUIList<std::vector<const Vehicle*>> does not call the destructor for each std::vector<const Vehicle*>.
Modifying SmallVector to call constructors and destructors seems to be a bad idea because it is used practically everywhere in the code (so other stuff might break). Also, it might become less performant.
There's also the possibility of storing the actual std::vector<const Vehicle*> somewhere else, and making the GUIList keep just a pointer, i.e. GUIList<std::vector<const Vehicle*>*>. But needing to store the actual data somewhere else seems needlessly complicated to me.