Transcript Unit 1 Introduction to Scratch

Unit 3 Music and Sound
Evangel College
S.2 ICT
Animal Piano Project
We will use the blocks in the Sound
category to build an Animal Piano project.
New sprite
At first, we add the key sprites.
Click the New Sprite From File button
New sprite
Click Costumes button on the left and then
choose crab1-a in the Animal folder.
Shrink and Rename
Click on the Shrink tool, then click on the
crab in order to shrink it.
Place it on the left hand side.
(Optional: Rename the sprite to “C Note”.)
Play a Note
Drag the PLAY NOTE block to the scripts area.
The value 60 represents middle C. Click on the
script. Can you hear the sound?
Key Press
Drag the KEY PRESS block on top of the PLAY
NOTE block. Change the key from “Space” to “a”.
Press “a” on the keyboard. Can you hear the middle
C sound?
Add other notes
You can change the note using the keyboard.
Add other notes
Prepare other notes:
C Note: 60 Key: a
G Note: 67 Key: g
D Note: 62 Key: s
A Note: 69 Key: h
E Note: 64 Key: d
B Note: 71 Key: j
F Note: 65 Key: f
C Note: 72 Key: k
Hint: You may duplicate the sprite and then change the costume.
Import the stage background
Choose the Stage
and then Import
Animal Piano Project
• Congratulations! You have created an
Animal Piano!
• Can you play a “happy birthday” song on it?
Challenging activities
Activity 1 (Change tempo):
Add script for the stage so that
• When the key “b” is pressed, the tempo
(beats per minute) increases, ie. faster.
• When the key “v” is pressed, the tempo
(beats per minute) decreases, ie. slower.
Challenging activities
Activity 2 (Change volume):
Add scripts for each sprite so that
• When the keys “up-arrow” is pressed,
the volume increases.
• When the keys “down-arrow” is pressed,
the volume decreases.
Challenging activities
Activity 3 (Change instrument):
Add scripts for each sprite so that
• When key “1” is pressed, the piano plays
Acoustic Grand sound.
• When key “2” is pressed, the piano plays
Violin sound.
Challenging activities
Activity 4 (Mouse control):
Add scripts for each sprite so that
• When the user clicks on the keyboard,
the piano plays sound too.
Programming concept: Event
Event
An event is triggered when something
happens. For example, when the user
presses a key on the keyboard, a key press
event is triggered.
There are many kinds of events, such as
Key Press event, Mouse Click event, Green
Flag event or even events triggered by
other sprites.
Programming concept: Event
Event driven programming
Any programming model which uses events
to run a specific portion of the program is
called event-driven programming.
Event capture and event handling
A sprite can capture the event and handle it.
For example, the cat sprite captures the
keyboard event and plays a note.
Summary
You have learnt:
• How to use SOUND blocks to build scripts
• How to new a Sprite, rename, resize and
move it
You have also learnt the following
programming concepts:
• Event – Happenings triggered by user or
other sprites