Computation as an Expressive Medium

1. Computation as an Expressive Medium Lab 1: Loops, Animation, and Simple User Interaction Jason Alderman *Slides blatantly stolen from Mayhew Seavey. Yoinks!

2. Lab Hours Thanks for your responses! I�ll send out an e-mail by the end of the day with with lab hours. And always feel free to e-mail me if you have questions. I�m at gtg362v@mail.gatech.edu . (If you forget, it�ll be on the whiteboard in here.)

3. What have you gone over? Window size and coordinate system Commenting code Variables Drawing primitives point line rect ellipse triangle print() and println() if(boolean){ do something }else{ do something} logic

4. What will we go over? Courseware! Variables: A Recap Drawing primitives (more info) Java Control Flow: Looping The Processing �draw()� looping function for animation Simple mouse interaction

5. Variables Variables are placeholders for your data.

6. Variables Two main types: Primitives and Objects Primitives: Boolean, Char, Byte, Short, Int, Long, Float, Double Objects: Everything else. Constructed with primitives as a base. For example, a �String� object is a series of Char variables.

7. More info on drawing primitives Zooooom on over to the reference pages�

8. Java Control Flow If-Then-Else: Conditional Logic

9. Java Control Flow: Looping Want to draw ten lines, evenly-spaced apart?

10. Java Control Flow: Looping Want to draw ten lines, evenly-spaced apart?

11. Java Control Flow: While Loops Holy Toledo! We can! Let�s use a while loop!

12. Java Control Flow: While Loops Be careful with loops. Make sure the condition will eventually return false, or else it will go forever.

13. Java Control Flow: For Loops For Loops are just like While loops, but a bit more compact for simple incrementing, like in our last example. These two loops are functionally the same:

14. Java Control Flow: Nested Loops Nesting of loops refers to putting one loop inside the brackets of another.

15. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

16. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

17. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

18. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

19. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

20. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

21. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

22. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

23. Java Control Flow: Nested Loops Still confused? Let�s look at this thing closer.

24. Java Control Flow: Nested Loops Nested Loops are especially useful for drawing in grid formations in a 2-D space. Think about how you could nest another loop inside to make a grid in a 3-D space.

25. The draw() function What is the draw() function? Processing allows you to put code in a special function called draw, which will run a number of times per second. For any graphics that you want to change over time, or have the user interact with, you�ll need to use the draw() function.

26. The draw() function Simple example:

27. The draw() function Simple example:

28. The draw() function Simple example:

29. The draw() function Simple example:

30. The setup() function You can use the setup() function to define some properties of your window once when your program first starts: size(width, height): size of drawing window (in pixels) framerate(fps): number of times per second that the draw() function is called.

31. Tracking Mouse Position Processing uses two global variables which have the current mouse position at all times: mouseX, mouseY: current X and Y of cursor, relative to the top-left of drawing window.

32. Reacting to Mouse Clicks Use the variable mousePressed.

33. That�s It For Today! For and While Loops Processing draw() function Mouse Position and Clicking