Baddie.cs

using Microsoft.Graphics.Canvas;
using Microsoft.Graphics.Canvas.UI.Xaml;


namespace Game
{

    // This class contains the code that draws and moves the "badguy" image.

    public class Baddie
    {
        public int x;
        public int y;
        private int direction;

        // Call this to set starting position and the direction that the baddie will start going in.
        public Baddie(int start_x, int start_y, int start_direction)
        {
            x = start_x;
            y = start_y;
            direction = start_direction;
        }

        public void Move(int speed, Maze gamemaze)
        {
            // Update the position of the baddie depending on the direction.
            // We can change the speed to make them faster or slower, and so
            // make the game harder or easier.

            switch (direction)
            {
                case 1: y -= speed; break;
                case 2: x += speed; break;
                case 4: y += speed; break;
                case 8: x -= speed; break;

                default: break;
            }

            // Test to see if the baddie is in the middle of a square in the maze, and then we can decide
            // to change direction or not.

            if ((x % 64 == 0) && (y % 64 == 0))
            {

                // Map the screen co-ordinates to the map co-ordinates 
                // (the screen is 1024 by 1024, the maze data is 16 by 16)

                int mx = (x / 64);
                int my = (y / 64);

                // Get the number that tells us the possible directions at this tile
                int possible_directions = gamemaze.GetTile(my, mx);

                // Define the opposite value to the current direction,
                // because we don't want to double back

                int opposite_directon = 0;

                if (direction == 1) opposite_directon = 4;
                if (direction == 2) opposite_directon = 8;
                if (direction == 4) opposite_directon = 1;
                if (direction == 8) opposite_directon = 2;

                int new_direction = 1;

                // Pick a new direction that is both possible AND not doubling back.
                do
                {
                    do
                    {

                        new_direction = gamemaze.NextDirection();
                    } while ((new_direction & possible_directions) == 0);
                } while (new_direction == opposite_directon);

                direction = new_direction;

            }
        }

        // Draw the baddie. Needs a reference to the canvas
        public void Draw(CanvasDrawEventArgs args, CanvasBitmap dino)
        {
            args.DrawingSession.DrawImage(dino, x + 4, y + 4);

        }
    }
}