•;If;Scratch;ever;hits;an;edge,;he;should
bounce. (That was another hint.)
•;He;should;only;face;left;or;right.;(This
one is tricky. Look for a set of tiny buttons on the top center panel.)
You’ll see some buttons that control
the cat’s orientation. Don’t be afraid to
experiment!
Shall We Dance?
After you’ve made the cat glide, it’s
time to make him dance. The goal is
something like this:
aharrisbooks.net/
scratchTutorial/ dance.html.
Note that Scratch seems to be changing
appearance. Sprites have images. Right
now your sprite always looks the same,
but he has two images, and you can add
as many as you want. We call the sprite
images “costumes.” If you look at the
center panel (where you’ve been making
scripts), you’ll see a Costumes tab. Click
on this tab, and you’ll see two costumes.
Click the copy button next to one of the
costumes and then click the Edit button.
Scratch includes a complete paint program! You can change your sprite image
or draw your own. You can also load an
image from the library or take a picture of
. . . Part of the fun is
working together with
a friend or parent
to discover how
everything works.
yourself with a web cam and use that as
the foundation of an image. I’ll stop here
and let you play, because these features
alone can keep you busy for some time.
Once you have a number of images
in a sprite, you can swap between them
pretty easily. Look for the Next Costume
button under the Looks tab. This will display the next costume in the list and cycle
through the list of costumes indefinitely.
If you swap images in a Forever loop,
the images might change too quickly to
be realistic. (My sprite looks a little frantic at full speed.) Look for a way to slow
things down (there’s a wait command in
controls—just saying . . .). The default
wait time is one second. That might be
too slow. Is there a way you can change
the speed of animations?
Tell a Joke
The next challenge is to use Scratch to tell
a simple joke. As usual, here’s a working
example. Warning: It’s a really bad joke:
aharrisbooks.net/scratchTutorial/joke
.html.
Here’s what this animation does:
•;It;has;two;sprites.
• Each sprite starts invisible and off
stage.
•;One;sprite;walks;in;and;calls;the;other.
•;The;second;sprite;comes;in.
•;They;tell;a;joke.
•;The;joke;deserves;a;rim;shot;(and;gets
one).
•;The;sprites;walk;off;stage;(.;.;.;and;none
too soon).
Planning and preparation are important parts of this project. First, find a better joke than mine that you want to tell.
Choose or create some characters and a
background. Once you’ve decided on the
characters, the plot, and the scene, you’ll
need to investigate a few new tricks to
make the program work.
You’ve probably used the Move 10
Steps command before, but this command is not the only way to manage
motion. Two numbers determine the
position of the sprite: X relates to the
