Function find_engine

plugins/siege-engine.cpp:366–408

static std::map<df::coord, df::building*> coord_engines;

static EngineInfo *find_engine(df::building *bld, bool create = false)
{
    auto ebld = strict_virtual_cast<df::building_siegeenginest>(bld);
    if (!ebld)
        return NULL;

    auto &obj = engines[bld];

    if (obj)
    {
        obj->bld = ebld;
        return obj;
    }

    if (!create || !is_build_complete(bld))
        return NULL;

    obj = new EngineInfo();

    obj->id = bld->id;
    obj->bld = ebld;
    obj->center = df::coord(bld->centerx, bld->centery, bld->z);
    obj->building_rect = coord_range(
        df::coord(bld->x1, bld->y1, bld->z),
        df::coord(bld->x2, bld->y2, bld->z)
    );
    obj->quality = average_quality(ebld);
    obj->is_catapult = (ebld->type == siegeengine_type::Catapult);
    obj->proj_speed = 2;
    obj->hit_delay = obj->is_catapult ? 2 : -1;
    obj->fire_range = get_engine_range(ebld, obj->quality);

    // Base coefficients per engine type, plus 6% exponential bonus per quality level
    obj->sigma_coeff = (obj->is_catapult ? 30.0 : 48.0) * pow(1.06f, obj->quality);

    obj->ammo_vector_id = job_item_vector_id::BOULDER;
    obj->ammo_item_type = item_type::BOULDER;

    obj->operator_id = obj->operator_frame = -1;

    coord_engines[obj->center] = bld;
    return obj;
}

static EngineInfo *find_engine(lua_State *L, int idx, bool create = false, bool silent = false)
{