Learning XNA 3.0

Creating a Sprite Class

Now you can go ahead and get started on your Sprite base class. What might you want to include in that class? Table 4-1 lists the members, and Table 4-2 lists the methods.

Table 4-1. Members of your Sprite class

Member	Type	Description
textureImage	Texture2D	Sprite or sprite sheet of image being drawn
position	Vector2	Position at which to draw sprite
frameSize	Point	Size of each individual frame in sprite sheet
collisionOffset	int	Offset used to modify frame-size rectangle for collision checks against this sprite
currentFrame	Point	Index of current frame in sprite sheet
sheetSize	Point	Number of columns/rows in sprite sheet
timeSinceLastFrame	int	Number of milliseconds since last frame was drawn
millisecondsPerFrame	int	Number of milliseconds to wait between frame changes
speed	Vector2	Speed at which sprite will move in both X and Y directions

Table 4-2. Methods of your Sprite class

Method	Return type	Description
Sprite(...) (multiple constructors)	Constructor	Sprite constructor method
Update(GameTime, Rectangle)	void	Handles all collision checks, movement, user input, and so on
Draw(GameTime, SpriteBatch)	void	Draws the sprite

This chapter will build upon the code that you created in Chapter 3. Open the code from that chapter and add a new class to your project by right-clicking on the project in Solution Explorer and selecting Add → Class. Name the new class file Sprite.cs ...