Slides from in-class lecture

1. THE TEAL EDITION
LIZ RUTLEDGE
rutle173@newschool.edu
DAY 4 esrutledge@gmail.com
August 4, 2011 cell phone: 415.828.4865

2. agenda.
Review: Do:
Homework PsuedoCode
+,-,*,% Logic for Ball Bounce
Data Types - String, int, float
Variables - assigning and good labelling
practices
Learn:
Drawing Curves
Operators - &&, ||, !=, ==, >
Conditionals - if, and, or, random, noise
Displaying text in the sketch window -
PFont, Create/Load Font, text()
PImage
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

3. review.
now wasn’t that fun?
homework:
questions?
let’s put that bad boy together
topics we covered yesterday:
+,-,*,%
Data Types - String, int, float
Variables - assigning and good labelling practices
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

4. curves.
like using the Illustrator pen tool...wearing a blindfold.
Curves Example:
http://www.openprocessing.org/visuals/?visualID=2124
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

5. conditionals!
the tool that allows you to do anything of
any actual interest...tever.
the operators: examples:
> greater than
println(3 > 5); // Prints what?
<= less than or equal to
< less than println(3 >= 5); // Prints what?
== equality
println(5 >= 3); // Prints what?
>= greater than or equal to
!= inequality println(3 == 5); // Prints what?
println(5 == 5); // Prints what?
what do they do? println(5 != 5); // Prints what?
return a boolean value of whether or not the
expression is in fact true
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

6. if statements.
1. The test must be an expression that resolves to true or false.
sample code: 2. When the test expression evaluates to true, the code inside the
if (test) { brackets is run. If the expression is false, the code is ignored.
statements 3. Code inside a set of braces is called a block.
}
examples:
int x = 150;
if (x > 100) { // If x is greater than 100,
ellipse(50, 50, 36, 36); // draw this ellipse
}
if (x < 100) { // If x is less than 100
rect(35, 35, 30, 30); // draw this rectangle
}
line(20, 20, 80, 80);
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

7. if-else statements.
adding complexity.
= a tree diagram made of code.
if (test) {
statements;
}
else { else = execute only if first test
statements 2; is not met
}
if (test) {
statements;
}
else if (test2) { else if = execute only if first test is
statements 2; not met AND second test IS met
}
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

8. logical operators.
sometimes one condition just
isn’t enough.
examples:
int a = 10;
int b = 20;
&& = AND if ((a > 5) || (b < 30)) {
line(20, 50, 80, 50);
|| = OR }
// Will the code in the block run?
! = NOT if ((a > 15) || (b < 30)) {
ellipse(50, 50, 36, 36);
}
// Will the code in the block run?
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

9. the “NOT” operator.
The logical NOT operator is an exclamation mark. It inverts the
logical value of the associated boolean variables. It changes true
to false, and false to true. The logical NOT operator can be applied
only to boolean variables.
examples:
boolean b = true; // Assign true to b
println(b); // Prints “true”
println(!b); // Prints “false”
println(!x); // ERROR! It’s only possible to ! a boolean variable
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

10. random.
sometimes you just need some random values.
The random() function creates unpredictable values within
the range specified by its parameters.
random(high) => returns a random number between 0 and the high parameter
random(low, high) => returns a random number between the low and the high parameter
examples:
float f = random(5.2); // Assign f a float value from 0 to 5.2
int i = random(5.2); // ERROR! Why?
int j = int(random(0,5.2)); // Assign j an int value from 0 to 5
println(j);
Use random sparingly and be conscious of the math and algorithm of a range of numbers,
rather than choosing random. Often used for color...but hey, let’s make our ranges specific!
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

11. text and images!
finally, something other than
shapes!
PFont()
How to use it:
createFont();
loadFont();
text();
PImage()
How to use it:
image();
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

12. pseudocode.
organize your thoughts to make the coding
part faster, easier and more accurate.
example:
if(stomach grumbling)
{
eat something, stupid!
}
else if (sleepy) {
just go to bed;
}
else {
keep watching tv like a lazy bum;
}
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

13. more pseudocode.
example:
if ((mouse position is in left half of canvas) AND (mouse position is in top half of canvas)) {
draw a orange rectangle in top left quarter of screen;
}
else {
draw a yellow rectangle in bottom right quarter of screen;
}
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

14. a bouncing ball.
let’s try out our sweet new
pseudocode skillz.
in-class activity:
go over logic of a bouncing ball as a class.
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011

15. homework.
optional subheading goes here.
do:
1) Write pseudocode for bouncing balls
2) Add label/text to drawing from the green painting tiles in an interesting way (i.e. not just
a line of text in the middle of the screen)
extra credit:
3) Write pseudocode for bouncing balls that respond realistically. Think the physics of a
billards table.
DAY 4
Tuesday, 4 Aug 2011
CODE
bootcamp 2011