+ // setting the video is required before you can run the engine and should
+ // probably be done before adding any layers
+ void setVideo(VideoP video);
+ VideoP getVideo() const;
+
+ void setTimestep(int ts);
+ int getTimestep() const;
+
+ void setMaxFps(int maxFps); // draw rate is always capped at the timestep
+ int getMaxFps() const;
+
+ int getFps() const;
+
+ void push(LayerP layer); // push a layer onto the top
+ LayerP pop(); // pop the top layer
+ LayerP pop(Layer* layer); // pops a specific layer and all layers above it
+ void clear(); // remove all layers (the engine will stop)
+
+ int getSize() const; // get the size of the stack
+
+ // set this machine in motion