Method doLaunchContents

plugins/siege-engine.cpp:1713–1788

    }

    void doLaunchContents()
    {
        // Translate cartoon flight speed to parabolic
        float speed = 100000.0f / (fall_delay + 1);
        int min_zspeed = (fall_delay+1)*4900;

        float bonus = 1.0f + 0.1f*(origin_pos.z -cur_pos.z);
        bonus *= 1.0f + (distance_flown - 60) / 200.0f;
        speed *= bonus;

        // Flight direction vector
        df::coord dist = target_pos - origin_pos;
        float vx = dist.x, vy = dist.y, vz = fabs((float)dist.z);
        normalize(vx, vy, vz);

        int start_z = 0;

        // Start at tile top, if hit a wall
        ProjectilePath path(origin_pos, target_pos);
        auto next_pos = path[distance_flown+1];
        if (next_pos.z == cur_pos.z && !isPassableTile(next_pos))
            start_z = 49000;

        bool forbid_ammo = DF_GLOBAL_VALUE(standing_orders_forbid_used_ammo, false);

        MapExtras::MapCache mc;
        std::vector<df::item*> contents;
        Items::getContainedItems(item, &contents);

        for (size_t i = 0; i < contents.size(); i++)
        {
            auto child = contents[i];

            if (forbid_ammo)
                child->flags.bits.forbid = true;

            // Liquids are vaporized so that they cover nearby units
            if (child->isLiquid())
            {
                auto flow = Maps::spawnFlow(
                    cur_pos,
                    flow_type::MaterialVapor,
                    child->getMaterial(), child->getMaterialIndex(),
                    100
                );

                // should it leave a puddle too?..
                if (flow && Items::remove(mc, child))
                    continue;
            }

            auto proj = Items::makeProjectile(mc, child);
            if (!proj) continue;

            bool keep = apply_impact_damage(child, 50000, int(250000*bonus));

            proj->flags.bits.no_impact_destroy = keep;
            //proj->flags.bits.bouncing = true;