Method addCost

MicropolisCore/src/MicropolisEngine/src/tool.h:180–184

* Add some amount to the total. */

 * Add some amount to the total.
 */
inline void ToolEffects::addCost(int amount)
{
    assert(amount >= 0); // To be on the safe side.
    this->cost += amount;
}

/**
 * Get the value of a map position.