Page 37 - Learn To Program With Scratch

Use this color to This part of the image has a
make any part of an white color.
image transparent.

This is what we see when
we paint the white part with
the transparent color.
This grid is the backdrop of
the Stage.

Figure 1-17: You can make any part of an image transparent by filling it with the “trans-
parent” color .

Now that you know your way around the Scratch interface, we’ll put
that knowledge to good use and make something fun. Roll up your sleeves
and get ready: We’re making a game!

Your first Scratch game

Pong .sb2 In this section, you’ll create a single-player game in which players will move
Pong_NoCode a paddle to keep a bouncing tennis ball from hitting the floor, based on the
.sb2 classic arcade game Pong. The user interface for our game is illustrated in
Figure 1-18.
When the game begins, the
ball starts here and moves
down at a random angle.

When the ball hits the
paddle, it bounces back
up at a random angle.
Use the mouse to move the
paddle horizontally.

If the ball touches this part of
the Stage, the game is over.

Figure 1-18: Our game screen

As shown in the figure, the ball starts at the top of the Stage and
moves down at some random angle, bouncing off the edges of the Stage.
The player moves the paddle horizontally (using the mouse) to send the
ball back up. If the ball touches the bottom of the Stage, it’s game over.
We’ll build this game one step at a time, but first we need to open a fresh
project. Select File4New to start a new Scratch project. Then delete the Cat
sprite by right-clicking it and selecting delete from the pop-up menu.

Getting Started 15

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