Datasheet

The Game1 class contains the Initialize, Update, and Draw methods mentioned a little bit earlier.

Initialize does nothing for now and Update just checks if the Back button on the first connected

gamepad was pressed.

For now you are just interested in the

Draw method, which basically just executes the following line to

clear the background to a specific color:

graphics.GraphicsDevice.Clear(Color.CornflowerBlue);

F5 and Go

If you press F5, the project starts (same as Debug-Start Debugging) and you see the screen shown in

Figure 1-11, which shows the blue color on a blank boring window that is specified in the

Draw method.

To feel like you are actually doing something, change the

Color to Color.Green and press F5 again.

The window now has a green background. The

Clear method of the graphics device has other over-

loads that can be used to clear the depth and stencil buffers, which will be done automatically if you just

set the color. For example, later in this book you will just need to clear the depth buffer, but not the color

of the background. To do that you just write the following line:

graphics.GraphicsDevice.Clear(ClearOptions.DepthBuffer,

Color.Green, 1, 0);

By default, the ClearOptions are set to ClearOptions.Target | ClearOptions.DepthBuffer,

which means both the background color and the depth buffer are cleared. By the way, if you don’t know

it already, the | operator between the

ClearOptions flags will combine both settings.

Figure 1-11

Part I: XNA Framework Basics

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