i might be a little delayed to chime in here, but
michael blunck wrote:
IIRC, "copper" is the only metal product in "basic tropic" and "in a hot country" economy, hence no collision with any other material. BTW, COPR was just an example, even more redundant labels are METL and STEL.
i think this is the wrong approach. If "metal" and "copper" are likely to have different sprites, they should very much have different cargo labels. there is no reason to minimize the total number of cargo labels across all GRFs. the only thing that achieves is that vehicle set authors must put in additional logic to determine which industry set is loaded to decide which sprite to draw, and the cargo labels was exactly meant to avoid that.
And BTW, take a look into our mess/list of cargo labels. There are already cargoes with no equivalence to their labels, and also the meaning of specific cargoes differ between different industry sets.
and this is the direct result of the above misguided attempt at "reusing" cargo labels, and "bending" them somehow onto your cargo, instead of using new "clean" ones.
You might not exactly be interested in Ferion
, but if you are, have fun