/// <summary>
/// LoadContent will be called once per game and is the place to load
/// all of your content.
/// </summary>
protected override void LoadContent()
{
// Create a new SpriteBatch, which can be used to draw textures.
spriteBatch = new SpriteBatch(GraphicsDevice);
MovingSprite ship = new MovingSprite(GraphicsDevice, "spaceShip", 1f);
// TODO: use this.Content to load your game content here
}
public override void Update(float elapsedTime)
{
//Pull all moving sprites towards the star
foreach (KeyValuePair <string, MovingSprite> kvp in movingSprites)
{
MovingSprite sprite = kvp.Value;
//Get sprite and gravObject positions
Vector2 gravObjectPos = new Vector2(this.x, this.y);
Vector2 spritePos = new Vector2(sprite.x, sprite.y);
//Calculate direction vector between GravObject and sprite
Vector2 dirVec = gravObjectPos - spritePos;
//Find the distance between ship and Gravobject
float distance = dirVec.Length();
//Normalize the direction vector
dirVec.Normalize();
//Accelerate the ship toward the star
float spritexAcc = dirVec.X * gravityStrength / distance;
float spriteyAcc = dirVec.Y * gravityStrength / distance;
//Update ship speed
sprite.xSpeed += spritexAcc * elapsedTime;
sprite.ySpeed += spriteyAcc * elapsedTime;
//Update ship position
sprite.x += sprite.xSpeed * elapsedTime;
sprite.y += sprite.ySpeed * elapsedTime;
}
}
public void AddtoAliens(string Key, MovingSprite sprite)
{
aliens.Add(Key, sprite);
}
public void AddtoMovingSprites(string Key, MovingSprite sprite)
{
movingSprites.Add(Key, sprite);
}