Arrows should be more customizable

[Renkineko]

If you want to make elemental arrow by example it's a little complicated right now. You can use custom entities but it's redundant to make arrow's behavior mimic the engine, if the engine change arrows become incoherent, etc.

[Renkineko]

A way for the customization : allow a max distance for the arrow, possibly changed if you are charging the bow. Like in Secret of Mana. Don't know if the system of charging the bow should be done in the engine side, in the quest side or both (don't see how to do it on quest side alone, but we could talk about it on irc :) )

[christopho]

To implement a bow in pure Lua, basically you have to freeze the hero, show a bow animation on the hero, and after some time shoot an arrow. The arrow can be custom entity with a straight movement that has a max_distance parameter.

(If custom entities had existed a long time ago, I probably would not have created built-in arrows and boomerangs.)

[ekureina]

Does ekureina/libsolarus-mudora@b08e321 suit your purposes, @Renkineko?

[Renkineko]

I don't really need this customization of a max distance, I often just say ideas others could use. I think in a first time, we should concentrate to reproduce exactly the actual built-in arrow, so with a max distance of 0 (or infinite if you prefer ^^). I didn't tested the code, but it does not have a condition to go on forever if max_distance = 0. With a collision listener testing if the entity is an arrow-sensitive entity, we should be good for the arrow.

Anyway, good job for this arrow, it seems good ^^

[christopho]

We won't improve built-in arrows after all. The right approach is to script them, this will be done in #517.