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Note that significant changes were made to the required contents of the Game.Draw method in XNA 4.0 as compared to XNA 3.1.
As you learned earlier, Update and Draw are called at different rates depending on whether IsFixedTimeStep is true or false.
If IsFixedTimeStep is false, Update and Draw will be called sequentially as often as possible.
If IsFixedTimeStep is true, Update will be called at the interval specified in TargetElapsedTime , while Draw will continue to be called as often as possible. For more information on fixed-step and variable-step game loops, see Application Model Overview ."
Because this program doesn't override the Update method, it doesn't matter how often the Draw method is called. Each time it is drawn, the sprite is drawn in the same position as shown in Figure 3 and Figure 4 .
According to the 2D Graphics Overview ,
According to the documentation for the Bitmap class,
According to the documentation ,
Working backwards through the above information, we started with an image file named gorightarrow.png . We manually added the file to the Content folder producing a game asset with an Asset Name of gorightarrow (see Figure 7 ).
Then we called the Load method in Listing 6 to load the contents of the file into an object of type Texture2D and saved that object's reference in the instance variable named myTexture . At that point in the process, we had converted the contents of our image fileinto a format that can be thought of as a sprite. The variable named myTexture contains a reference to our sprite.
The Game.Draw method begins in Listing 7 . I am referring to the method here as Game.Draw to distinguish it from the method named SpriteBatch.Draw , which we will encounter shortly.
Listing 7 . Beginning of the Game.Draw method.
protected override void Draw(GameTime gameTime) {
GraphicsDevice.Clear(Color.CornflowerBlue); Each time the Game.Draw method is executed, the incoming parameter contains time information encapsulated in an object of type GameTime . According to the documentation, the GameTime object provides a
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