book

Getting Started with Processing

by Casey Reas, Ben Fry

June 2010

Beginner

210 pages

3h 45m

English

Make: Community

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A Note Regarding Supplemental Files
Advance Praise for Getting Started with Processing
Preface
How This Book Is OrganizedWho This Book Is ForConventions Used in This BookUsing Code ExamplesHow to Contact UsSafari® Books OnlineAcknowledgments
1. Hello
Sketching and PrototypingFlexibilityGiantsFamily TreeJoin In
2. Starting to Code
Your First ProgramExample 2-1: Draw an EllipseExample 2-2: Make CirclesShowSaveShareExamples and Reference
3. Draw
Example 3-1: Draw a WindowExample 3-2: Draw a PointBasic ShapesExample 3-3: Draw a LineExample 3-4: Draw Basic ShapesExample 3-5: Draw a RectangleExample 3-6: Draw an EllipseExample 3-7: Draw Part of an EllipseExample 3-8: Draw with DegreesDrawing OrderExample 3-9: Control Your Drawing OrderExample 3-10: Put It in ReverseShape PropertiesExample 3-11: Draw Smooth LinesExample 3-12: Set Stroke WeightExample 3-13: Set Stroke AttributesColorExample 3-14: Paint with GraysExample 3-15: Control Fill and StrokeExample 3-16: Draw with ColorExample 3-17: Set TransparencyCustom ShapesExample 3-18: Draw an ArrowExample 3-19: Close the GapExample 3-20: Create Some CreaturesCommentsRobot 1: Draw
4. Variables
Example 4-1: Reuse the Same ValuesExample 4-2: Change ValuesMaking VariablesProcessing VariablesExample 4-3: Adjust the Size, See What FollowsA Little MathExample 4-4: Basic ArithmeticRepetitionExample 4-5: Do the Same Thing Over and OverExample 4-6: Use a for LoopExample 4-7: Flex Your for Loop’s MusclesExample 4-8: Fanning Out the LinesExample 4-9: Kinking the LinesExample 4-10: Embed One for Loop in AnotherExample 4-11: Rows and ColumnsExample 4-12: Pins and LinesExample 4-13: Halftone DotsRobot 2: Variables
5. Response
Example 5-1: The draw() FunctionExample 5-2: The setup() FunctionExample 5-3: setup(), Meet draw()FollowExample 5-4: Track the MouseExample 5-5: The Dot Follows YouExample 5-6: Draw ContinuouslyExample 5-7: Set Thickness on the FlyExample 5-8: Easing Does ItExample 5-9: Smooth Lines with EasingMapExample 5-10: Map Values to a RangeExample 5-11: Map with the map() FunctionClickExample 5-12: Click the MouseExample 5-13: Detect When Not ClickedExample 5-14: Multiple Mouse ButtonsLocationExample 5-15: Find the CursorExample 5-16: The Bounds of a CircleExample 5-17: The Bounds of a RectangleTypeExample 5-18: Tap a KeyExample 5-19: Draw Some LettersExample 5-20: Check for Specific KeysExample 5-21: Move with Arrow KeysRobot 3: Response
6. Media
ImagesExample 6-1: Load an ImageExample 6-2: Load More ImagesExample 6-3: Mousing Around with ImagesExample 6-4: Transparency with a GIFExample 6-5: Transparency with a PNGFontsExample 6-6: Drawing with FontsExample 6-7: Draw Text in a BoxExample 6-8: Store Text in a StringShapesExample 6-9: Draw with ShapesExample 6-10: Scaling ShapesRobot 4: Media
7. Motion
Example 7-1: See the Frame RateExample 7-2: Set the Frame RateSpeed and DirectionExample 7-3: Move a ShapeExample 7-4: Wrap AroundExample 7-5: Bounce Off the WallTweeningExample 7-6: Calculate Tween PositionsRandomExample 7-7: Generate Random ValuesExample 7-8: Draw RandomlyExample 7-9: Move Shapes RandomlyTimersExample 7-10: Time PassesExample 7-11: Triggering Timed EventsCircularExample 7-12: Sine Wave ValuesExample 7-13: Sine Wave MovementExample 7-14: Circular MotionExample 7-15: SpiralsTranslate, Rotate, ScaleExample 7-16: Translating LocationExample 7-17: Multiple TranslationsExample 7-18: Isolating TransformationsExample 7-19: RotationExample 7-20: Combining TransformationsExample 7-21: ScalingExample 7-22: Keeping Strokes ConsistentExample 7-23: An Articulating ArmRobot 5: Motion

8. Functions
Function BasicsExample 8-1: Roll the DiceExample 8-2: Another Way to RollMake a FunctionExample 8-3: Draw the OwlExample 8-4: Two’s CompanyExample 8-5: An Owl FunctionExample 8-6: Increasing the Surplus PopulationExample 8-7: Owls of Different SizesReturn ValuesExample 8-8: Return a ValueRobot 6: Functions
9. Objects
Classes and ObjectsDefine a ClassExample 9-1: Make an ObjectExample 9-2: Making Multiple ObjectsRobot 7: Objects
10. Arrays
Example 10-1: Many VariablesExample 10-2: Too Many VariablesExample 10-3: Arrays, Not VariablesMake an ArrayExample 10-4: Declare and Assign an ArrayExample 10-5: Compact Array AssignmentExample 10-6: Assigning to an Array in One GoExample 10-7: Revisiting the First ExampleRepetition and ArraysExample 10-8: Filling an Array in a for LoopExample 10-9: Track Mouse MovementsArrays of ObjectsExample 10-10: Managing Many ObjectsExample 10-11: Sequences of ImagesRobot 8: Arrays
11. Extend
3DExample 11-1: A 3D DemoExample 11-2: LightingExample 11-3: The Processing CameraImage ExportExample 11-4: Saving ImagesExample 11-5: Draw to a PDFHello ArduinoExample 11-6: Read a SensorExample 11-7: Read Data from the Serial PortExample 11-8: Visualizing the Data StreamExample 11-9: Another Way to Look at the DataCommunity
A. Coding Tips
Functions and ParametersColor CodingCommentsUppercase and LowercaseStyleConsoleOne Step at a Time
B. Data Types
C. Order of Operations
D. Variable Scope
Index
About the Authors
Colophon
Copyright

Content preview from Getting Started with Processing

Chapter 4. Variables

A variable stores a value in memory so that it can be used later in a program. The variable can be used many times within a single program, and the value is easily changed while the program is running.

The primary reason we use variables is to avoid repeating ourselves in the code. If you are typing the same number more than once, consider making it into a variable to make your code more general and easier to update.

Example 4-1: Reuse the Same Values

For instance, when you make the y-coordinate and diameter for the two circles in this example into variables, the same values are used for each ellipse:

size(480, 120);
smooth();

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Getting Started with Processing

by Casey Reas, Ben Fry

Chapter 4. Variables

Example 4-1: Reuse the Same Values

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