Method isOnUnmovableItem

plugins/suspendmanager.cpp:317–372

True for buildings planned on a tile with an item that cannot be moved aside

    // True for buildings planned on a tile with an item that cannot be moved aside
    static bool isOnUnmovableItem(df::job *job) {
        CHECK_NULL_POINTER(job);
        auto building = Job::getHolder(job);
        if (!building)
            return false;

        // Check for items on the building, look into all the map blocks overlapping
        // the building
        bool has_item = false;
        for (int32_t block_x = building->x1 >> 4; block_x <= building->x2 >> 4; ++block_x) {
            for (int32_t block_y = building->y1 >> 4; block_y <= building->y2 >> 4; ++block_y) {
                auto block = Maps::getBlock(block_x,block_y,building->z);
                if (!block)
                    continue;

                for (df::item *item : block->items | transform(df::item::find)) {
                    if (!item)
                        continue;
                    if (item->pos.x < building->x1 || item->pos.x > building->x2 ||
                        item->pos.y < building->y1 || item->pos.y > building->y2)
                        continue;

                    // Ok if it's an item of the job
                    if (std::ranges::any_of(job->items, [item](df::job_item_ref *j) {return j->item == item;}))
                        continue;
                    if (item->flags.bits.in_job || item->flags.bits.forbid)
                        return true; // Assigned to a different task or forbidden, not movable
                    has_item = true;
                }
            }
        }

        if (!has_item)
            return false;

        // When there is an item on top of the building, check for the surrounding of the building
        // for a place where the dwarves would be able to move the item to.
        // The dwarves will move an item if there is a walkable space without any
        // building planned, non-diagonally neighbouring the building.
        // The position of the item does not matter, in multi-tile buildings
        // dwarves will move the item multiple tiles if necessary
        for (auto x : {building->x1-1, building->x2+1}) {
            for (auto y = building->y1; y <= building->y2; ++y) {
                if (suitableToMoveItemTo(coord(x,y,building->z)))
                    return false;
            }
        }
        for (auto y : {building->y1-1, building->y2+1}) {
            for (auto x = building->x1; x <= building->x2; ++x) {
                if (suitableToMoveItemTo(coord(x,y,building->z)))
                    return false;
            }
        }

        return true;
    }

    // check if the tile is suitable tile to stand on for construction (walkable & not a tree branch)