使用泛型和向上转换的最佳方法

Question

我具有以下对象，用于执行某些地图导航逻辑：

public interface Node
{
    //.. PathFinder needs this stuff
}

public class MapTile : Node
{
    //.. PathFinder doesn't need this stuff
}

public interface Pathable<T> where T : Node
{
    //.. contains contextual information related to movement that the path finder needs, like whether the agent is walking or flying
}

public class WalkAction : Pathable<MapTile>
{
    //.. PathFinder doesn't need this stuff
}

public static class PathFinder
{
    public static void FindPath(Node start, Node end, Pathable<Node> context)
    {
         //.. logic to find the path
    }
}


public void main()
{   
    WalkAction walkContext = CreateWalkContext();        
    MapTile[] map = CreateMap();
    PathFinder.FindPath(map[0], map[42], walkContext);
}

编译器抱怨我使用“ PathFinder.FindPath”，因为无法将WalkAction类型的对象转换为Pathable 。

从概念上讲，这是为什么？如果我想让寻路逻辑（应该只处理节点和一些上下文信息）与我更具体的实现逻辑清晰地分开，是否有一种更聪明的结构方式？