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[rbdr/super-polarity] / SuperPolarity / Actors / Actor.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using Microsoft.Xna.Framework;
using Microsoft.Xna.Framework.Content;
using Microsoft.Xna.Framework.Graphics;

namespace SuperPolarity
{
    public class Actor
    {
        protected SuperPolarity game;

        public List<Actor> Children;

        // In-Game Properties
        public bool Active;
		public Rectangle Box;
		public Vector4 BoxDimensions;
		protected Texture2D BoxTexture;
		protected Color Color;

        // Physical Properties
        public Vector2 Position;
		public bool Collides;
        protected Vector2 Velocity;
        protected Vector2 Acceleration;
        public float Angle;

        // Constraints / Behavior
        public float MaxVelocity;
		protected float AccelerationRate;
        public bool Dying;

        public Actor Parent;

        public virtual int Width
        {
            get { return 0; }
        }

        public virtual int Height
        {
            get { return 0; }
        }

        public Actor(SuperPolarity newGame)
        {
            game = newGame;
			BoxDimensions.X = 20;
			BoxDimensions.Y = 20;
			BoxDimensions.W = 15;
			BoxDimensions.Z = 15;
        }

        public virtual void Initialize(Vector2 position)
        {
            Position = position;
            Active = true;

			Collides = false;

            Children = new List<Actor>();

            Velocity = new Vector2(0, 0);
            Acceleration = new Vector2(0, 0);

            MaxVelocity = 5;
            AccelerationRate = 10;

            Dying = false;

			InitBox();
			BoxTexture = new Texture2D(game.GraphicsDevice, 1, 1);
			BoxTexture.SetData(new Color[] { Color.White });

            Color = Color.White;
        }

		protected void InitBox()
		{
			Box = new Rectangle((int)(Position.X - BoxDimensions.X), (int)(Position.Y - BoxDimensions.X), (int)(BoxDimensions.X + BoxDimensions.X + BoxDimensions.W), (int)(BoxDimensions.Y + BoxDimensions.Y + BoxDimensions.Z));
		}

        public void AutoDeccelerate(GameTime gameTime)
        {
            if (Acceleration.X == 0 && Velocity.X > 0)
            {
                if (AccelerationRate * gameTime.ElapsedGameTime.TotalSeconds > Velocity.X)
                {
                    Velocity.X = 0;
                    Acceleration.X = 0;
                }
                else
                {
                    Acceleration.X = -AccelerationRate;
                }
            }

            if (Acceleration.X == 0 && Velocity.X < 0)
            {
                if (-AccelerationRate * gameTime.ElapsedGameTime.TotalSeconds < Velocity.X)
                {
                    Velocity.X = 0;
                    Acceleration.X = 0;
                }
                else
                {
                    Acceleration.X = AccelerationRate;
                }
            }

            if (Acceleration.Y == 0 && Velocity.Y > 0)
            {
                if (AccelerationRate * gameTime.ElapsedGameTime.TotalSeconds > Velocity.Y)
                {
                    Velocity.Y = 0;
                    Acceleration.Y = 0;
                }
                else
                {
                    Acceleration.Y = -AccelerationRate;
                }
            }

            if (Acceleration.Y == 0 && Velocity.Y < 0)
            {
                if (-AccelerationRate * gameTime.ElapsedGameTime.TotalSeconds < Velocity.Y)
                {
                    Velocity.Y = 0;
                    Acceleration.Y = 0;
                }
                else
                {
                    Acceleration.Y = AccelerationRate;
                }
            }
        }

        public virtual void Update(GameTime gameTime)
        {
            Move(gameTime);
            ChangeAngle();
            CheckOutliers();
			UpdateBox ();
        }

		protected virtual void UpdateBox()
		{
			Box.X = (int)(Position.X - BoxDimensions.X);
			Box.Y = (int)(Position.Y - BoxDimensions.Y);
		}

        public virtual void Move(GameTime gameTime)
        {
            AutoDeccelerate(gameTime);

            Velocity.X = Velocity.X + Acceleration.X * (float)gameTime.ElapsedGameTime.TotalSeconds;
            Velocity.Y = Velocity.Y + Acceleration.Y * (float)gameTime.ElapsedGameTime.TotalSeconds;

            if (Velocity.X > MaxVelocity)
            {
                Velocity.X = MaxVelocity;
            }

            if (Velocity.X < -MaxVelocity)
            {
                Velocity.X = -MaxVelocity;
            }

            if (Velocity.Y > MaxVelocity)
            {
                Velocity.Y = MaxVelocity;
            }

            if (Velocity.Y < -MaxVelocity)
            {
                Velocity.Y = -MaxVelocity;
            }

            Position.X = Position.X + Velocity.X;
            Position.Y = Position.Y + Velocity.Y;
        }

        public void ChangeAngle()
        {
            if (Math.Abs(Velocity.Y) <= 0.1 && Math.Abs(Velocity.X) <= 0.1)
            {
                return;
            }
            Angle = (float)Math.Atan2(Velocity.Y, Velocity.X);
        }

        public virtual void Draw(SpriteBatch spriteBatch)
        {
            Actor child = null;
            
            //  TODO: Check what's up with the null children.
            if (Children == null)
            {
                return;
            }
            for (var i = Children.Count - 1; i >= 0; i--)
            {
                child = Children[i];
                child.Draw(spriteBatch);
            }

			//spriteBatch.Draw(BoxTexture, Box, new Color(255, 0, 255, 25));
        }

        void CheckOutliers()
        {
            for (var i = Children.Count; i > 0; i--)
            {
                var actor = Children[i - 1];
                if (actor.Position.X < -SuperPolarity.OutlierBounds || actor.Position.Y < -SuperPolarity.OutlierBounds ||
                    actor.Position.X > game.GraphicsDevice.Viewport.Width + SuperPolarity.OutlierBounds ||
                    actor.Position.Y > game.GraphicsDevice.Viewport.Height + SuperPolarity.OutlierBounds)
                {
                    Children.Remove(actor);
                }
            }
        }

        public virtual void Collide(Actor other, Rectangle collision)
        {
        }

        protected virtual void Die()
        {
            Dying = true;
        }

        public virtual void CleanUp()
        {
			BoxTexture = null;
			Children = null;
        }
    }
}