Scratch 2.0 Beginner's Guide电子书

Scratch 2.0 Beginner's Guide Second Edition

Table of Contents

Scratch 2.0 Beginner's Guide Second Edition

Credits

About the Author

About the Reviewers

www.PacktPub.com

Support files, eBooks, discount offers, and more

Why Subscribe?

Free Access for Packt account holders

Preface

What this book covers

What you need for this book

Who this book is for

Conventions

Time for action – heading

What just happened?

Pop quiz – heading

Have a go hero – heading

Reader feedback

Customer support

Downloading the example code

Downloading the color images of this book

Errata

Piracy

Questions

1. Welcome to Scratch 2.0

About Scratch

Encouraging everyone to think programmatically

Sample Scratch uses

Computational thinking

Finding a project for you

Making animations

Telling stories

Building games

Programming games of chance

Creating art projects

Sensing the real world

Programming concepts

Using Scratch 2.0

Looking inside a Scratch project

The stage area

The sprites pane

The scripts area

The built-in image editor

Using Scratch 2.0 offline

Encountering Scratch 1.4

Tinkering encouraged

Summary

2. A Quick Start Guide to Scratch

Joining the Scratch community

Time for action – creating an account on the Scratch website

What just happened?

Time for action – understanding the key features of your account

What just happened?

Abiding by the terms of use

Creating projects under Creative Commons licenses

Finding free media online

Taking our first steps in Scratch

Time for action – moving the cat across the stage

What just happened?

Using events to trigger an action

Have a go hero – testing the move block

Time for action – animating a walking motion with the cat

What just happened?

Understanding the basics of a Scratch Project

Saving early, often, and automatically

Time for action – saving our work

What just happened?

Undoing a deletion

Introducing forever loops

Time for action – setting the cat in motion, forever

What just happened?

Controlling a sprite with loops

Time for action – flipping the cat right-side up

What just happened?

Clicking on a block runs the command

Have a go hero – exploring sprite rotation

Adding sprites to the project

Time for action – adding a second sprite and script

What just happened?

Reviewing a video-sensing project

Time for action – reviewing pop the balloon - video starter

What just happened?

Sensing video

Have a go hero – remixing ideas with our starter project

Pop quiz – getting started with Scratch

Summary

3. Creating an Animated Birthday Card

Introducing the paint editor

Time for action – painting a happy birthday sprite

What just happened?

Changing the size of a bitmap image

Choosing bitmap or vector images

Time for action – drawing a vector image

What just happened?

Changing the size of the vector image

Reviewing the image editing tools

Erasing in the vector mode

Filling the stage with color

Time for action – using the fill with color tool to paint the stage

What just happened?

Adding gradients

Time for action – applying a gradient

What just happened?

Time for action – adding more sprites to address the card

What just happened?

Initializing a sprite's starting values

Time for action – hiding all sprites when the flag is clicked

What just happened?

Time for action – displaying happy birthday

What just happened?

Specifying memorable names and comments

Time for action – renaming sprites

What just happened?

Inserting comments into our code

Time for action – adding comments to a script

What just happened?

Transforming sprites with graphical effects

Time for action – transforming sprites

What just happened?

Graphical transformations

Comparing the repeat and forever blocks

Time for action – turning m in a circle

What just happened?

Have a go hero – cleaning up the animations

Time for action – making a sprite fade in with the ghost effect

What just happened?

Two ways to control timing

Have a go hero – animating the butterfly

Pop quiz – reviewing the chapter

Summary

4. Creating a Scratch Story Book

Designing the outline of a barnyard joke book

Time for action – designing a clickable table of contents

What just happened?

Time for action – adding pages to the book

What just happened?

Time for action – adding a sprite to the Backpack

What just happened?

Using the Backpack to store sprites and scripts

Building a joke with say blocks and sounds

Time for action – making a horse talk with the say block

What just happened?

Time for action – synchronizing and animating the horse

What just happened?

Time for action – importing a horse sound

What just happened?

Playing supported sound formats

Positioning a sprite by its coordinates

Time for action – moving the dog based on x and y coordinates

What just happened?

Locating sprites with x and y coordinates

Creating a new costume

Time for action – duplicating, flipping, and switching a sprite's costume

What just happened?

Comparing costumes to sprites

Composing custom sound effects

Time for action – creating drum sound effects

What just happened?

Creating sound effects and music

Have a go hero – writing a joke sequence for the dog

Time for action – integrating the dog's joke sequence

What just happened?

Have a go hero – adding context to the dog's scene

Navigating the story and coordinating scenes

Time for action – hiding the table of contents

What just happened?

Time for action – displaying the dog scene

What just happened?

Coordinating scenes by backdrop name

Time for action – navigating back to the table of contents

What just happened?

Have a go hero – finishing the sequence and initializing the project

Pop quiz – checking chapter concepts

Summary

5. Creating a Multimedia Slideshow

Importing photos as backdrops

Time for action – importing photos from files

What just happened?

Working with images

Resizing images

Using caution while resizing images

Have a go hero – importing an animated GIF or vector graphic

Adding slideshow controls to display images

Time for action – flipping through the photos

What just happened?

Related backdrop blocks

Playing and recording sounds

Time for action – adding a sound from Scratch's library

What just happened?

Time for action – recording sounds in the sound editor

What just happened?

Understanding sound related blocks

Editing sounds

Time for action – editing a recorded sound

What just happened?

Time for action – appending a sound

What just happened?

Time for action – adding sound effects to recordings

What just happened?

Reviewing available sound effects

Have a go hero – narrating additional images

Using x and y coordinates to find the position of the mouse's pointer

Time for action – using mouse location to hide arrows

What just happened?

Have a go hero – redefining the hot zone

Time for action – providing user instructions

What just happened?

Displaying a project in presentation mode

Time for action – presenting a fullscreen slideshow

What just happened?

Have a go hero – personalizing the slideshow with graphic effects

Pop quiz – reviewing the chapter's concepts

Summary

6. Making an Arcade Game – Breakout (Part I)

Learning about the Breakout game

Discovering Pong

Time for action – importing and playing the Pong starter project

What just happened?

Remixing a legacy Scratch project

Moving a sprite with the mouse or arrows

Using reporter blocks to set values

Customizing the gameplay of the Pong project

Time for action – adding the left and right arrow controls

What just happened?

Evaluating the y position of the ball to end the game

Time for action – determining if the ball is below the paddle

What just happened?

Time for action – adjusting the center of a sprite costume

What just happened?

Have a go hero – using the costume center in projects

Cloning to create identical sprites

Time for action – drawing bricks

What just happened?

Time for action – cloning bricks

What just happened?

Dealing with the cloned sprite

Time for action – breaking bricks when I start as a clone

What just happened?

Cloning explained

Rapid fire shooting with cloning

Cloning related blocks

Ricocheting with the point in direction block

Time for action – changing a sprite's direction

What just happened?

Figuring out the direction

Time for action – setting the starting position and the direction

What just happened?

Time for action – ricocheting off bricks

What just happened?

Conditional statements

Conditional statements in real life

Defining a variable to keep score

Time for action – adding a score variable

What just happened?

Setting variables For all sprites

Setting variables For this sprite only

Have a go hero – creating a graphical effect for the bricks

Pop quiz – reviewing the chapter

Summary

7. Programming a Challenging Gameplay – Breakout (Part II)

Implementing lives

Time for action – adding a variable to track lives

What just happened?

Time for action – checking for game over

What just happened?

Evaluating multiple programming solutions

Have a go hero – programming a character's health

Adding more bricks to the level with a custom block

Time for action – creating a second brick

What just happened?

Time for action – drawing rows of bricks with custom blocks

What just happened?

Introducing procedures by way of custom blocks

Setting custom block inputs

Have a go hero – creating a custom block with options

Time for action – coordinating the ball play

What just happened?

Increasing ball speed and difficulty

Time for action – increasing ball speed

What just happened?

Using Boolean evaluations

Keeping score based on a clone's costume

Time for action – decreasing the paddle size based on the clones' costume

What just happened?

Considering alternative solutions

Time for action – detecting when we clear the level

What just happened?

Keeping the score using cloud variables

Time for action – keeping a global scoreboard

What just happened?

Understanding cloud variables in Scratch 2.0

Viewing the cloud data log

Pop quiz – reviewing the chapter's concepts

Have a go hero – extending Breakout

Summary

8. Chatting with a Fortune Teller

Creating, importing, and exporting lists

Time for action – creating lists to store multiple values

What just happened?

Working with an item in a list

Importing a list

Time for action – importing fortunes to a list

What just happened?

Exporting a list from Scratch

Prompting the player for a question

Time for action – asking a question

What just happened?

Using stored questions

Time for action – validating the seeker's question

What just happened?

Deleting the list values

Have a go hero – finding and using the player's username

Selecting a random fortune

Time for action – selecting a random fortune

What just happened?

Time for action – counting our fortunes with mod

What just happened?

Using magic numbers

Creating a custom say fortune block

Time for action – creating a custom say fortune block

What just happened?

Using the if () then else block

Manipulating the text

Time for action – ensuring grammatically correct questions

What just happened?

Testing your project

Creating a keyword scanner

Time for action – scanning a text string to build a list of words

What just happened?

Have a go hero – creating a more intelligent chat bot

Pop quiz – understanding how to work with text

Summary

9. Turning Geometric Patterns into Art Using the Pen Tool

Drawing basic shapes

Time for action – drawing our first square

What just happened?

Have a go hero – exploring squares

Time for action – building on the square

What just happened?

Drawing user-defined shapes

Time for action – enabling the user to create custom shapes

What just happened?

Time for action – turning triangles into pinwheels

What just happened?

Have a go hero – adding a stem to the flower

Defining procedures for home and shapes

Time for action – creating a custom shapes procedure

What just happened?

Plotting the coordinates of shapes

Time for action – plotting x,y coordinates to draw a square

What just happened?

Understanding and using color

Time for action – coloring our shapes

What just happened?

Understanding color shades

Working with the set pen color to () block

Time for action – finding a color picker workaround

What just happened?

Finding a color to use by its number

Time for action – creating a color palette

What just happened?

Have a go hero – finding all shades for a color

Adding color slider inputs to the shapes project

Time for action – limiting color values with a slider

What just happened?

Have a go hero – expanding the shapes application

Creating asymmetrical patterns

Time for action – creating an explosion

What just happened?

Turning straight lines into string art

Time for action – animating a radar screen

What just happened?

Time for action – breaking out of the circle

What just happened?

Have a go hero – twisting your perspective

Pop quiz – getting into shape

Summary

A. Connecting a PicoBoard to Scratch 1.4

Using Scratch 1.4, the PicoBoard, and Raspberry Pi

Finding Scratch 1.4

Purchasing the PicoBoard

Time for action – enabling and testing the PicoBoard support in Scratch 1.4

What just happened?

Adding the PicoBoard support to Scratch 2.0

Animating webcam images by detecting sound

Time for action – creating a talking head

What just happened?

Have a go hero – using sound to move a sprite forward and backward

Sharing Scratch 1.4 projects online

Sensing the environment with the PicoBoard

Measuring resistance

Time for action – recording the resistance of a thermistor over time

What just happened?

Completing a circuit

Time for action – charting our measurements

What just happened?

Interpreting the graph

Time for action – revising the graph

What just happened?

Have a go hero – brainstorming data collection topics

Pop quiz – connecting to the real world

Summary

B. Pop Quiz Answers

Chapter 2, A Quick Start Guide to Scratch

Pop quiz – getting started with scratch

Chapter 3, Creating an Animated Birthday Card

Pop quiz – reviewing the chapter

Chapter 4, Creating a Scratch Story Book

Pop quiz – reviewing the chapter

Chapter 5, Creating a Multimedia Slideshow

Pop quiz – reviewing the chapter

Chapter 6, Making an Arcade Game – Breakout (Part I)

Pop quiz – reviewing the chapter

Chapter 9, Turning Geometric Patterns into Art Using the Pen Tool

Pop quiz – getting into shape

Appendix A, Connecting a PicoBoard to Scratch 1.4

Pop quiz – connecting to the real world

Index