Creative Coding Week 2: Crazy Clocks
The purpose of this exercise is to ensure an understanding of looping and conditions. A sketch was supplied that shows 25 clocks, each with one hand that rotates anti-clockwise at varying speeds. Our task was to change every second round clock face to a square clockface and reverse the direction of the hands on those clocks.
This is the sketch supplied in the course.
> View source code for preceding sketch.
/*
* Creative Coding
* Week 2, 04 - The Clocks
* by Indae Hwang and Jon McCormack
* Copyright (c) 2014 Monash University
*
* This program draws a grid of circular "clocks", whose hands move according to the elasped time.
* The higher the clock number the faster it moves, the first clock takes 1 min to go all the way around.
* The function "movingCircle" is used to draw each clock. It is passed the position, size and hand angle
* as arguments.
*
*/
void setup() {
size(600, 600);
background(180);
rectMode(CENTER);
noStroke();
}
void draw() {
background(180);
noStroke();
int num = 5;
int margin = 80;
float gutter = 0; //distance between each cell
float cellsize = ( width - (2 * margin) - gutter * (num - 1) ) / (num - 1);
int circleNumber = 0; // counter
for (int i=0; i < num; i++) {
for (int j=0; j < num; j++) {
++circleNumber;
float tx = margin + cellsize * i + gutter * i;
float ty = margin + cellsize * j + gutter * j;
movingCircle(tx, ty, cellsize, circleNumber * TWO_PI * millis() / 60000.0);
}
}
}//end of draw
void movingCircle(float x, float y, float size, float angle) {
// calculate endpoint of the line
float tempX = x + (size / 2) * sin(angle);
float tempY = y + (size / 2) * cos(angle);
stroke(0);
strokeWeight(1);
fill(140, 180);
ellipse(x, y, size, size); // circle
stroke(255, 0, 0);
line(x, y, tempX, tempY); // red line
}
I completed the exercise by testing whether a counter was odd or even and drawing a circle or square depending on the result of the test. The rirection in which the hands rotate was changed by changing the sign of the angle used to calculate the line used for the hand. All the trigonometry I learnt in high school has seeped away over the years. I am having to relearn it.
> View source code for preceding sketch.
/*
* Creative Coding
* Week 2, 04 - The Clocks
* by Indae Hwang and Jon McCormack
* Copyright (c) 2014 Monash University
*
* This program draws a grid of circular "clocks", whose hands move according to the elasped time.
* The higher the clock number the faster it moves, the first clock takes 1 min to go all the way around.
* The function "movingCircle" is used to draw each clock. It is passed the position, size and hand angle
* as arguments.
*
* Amended by Gerard Holden to change every second clockface from circular to square and to reverse the
* direction of the hands on those clocks.
*/
void setup() {
size(600, 600);
background(180);
rectMode(CENTER);
noStroke();
}
void draw() {
background(180);
noStroke();
int num = 5;
int margin = 80;
float gutter = 0; //distance between each cell
float cellsize = ( width - (2 * margin) - gutter * (num - 1) ) / (num - 1);
int circleNumber = 0; // counter
for (int i=0; i < num; i++) {
for (int j=0; j < num; j++) {
++circleNumber;
float tx = margin + cellsize * i + gutter * i;
float ty = margin + cellsize * j + gutter * j;
if(circleNumber % 2 == 0) {
movingCircle2(tx, ty, cellsize, circleNumber * TWO_PI * millis() / 60000.0);
} else {
movingCircle(tx, ty, cellsize, circleNumber * TWO_PI * millis() / 60000.0);
}
}
}
}//end of draw
void movingCircle(float x, float y, float size, float angle) {
// calculate endpoint of the line
float tempX = x + (size / 2) * sin(angle);
float tempY = y + (size / 2) * cos(angle);
stroke(0);
strokeWeight(1);
fill(140, 180);
ellipse(x, y, size, size); // circle
stroke(255, 0, 0);
line(x, y, tempX, tempY); // red line
}
void movingCircle2(float x, float y, float size, float angle) {
// calculate endpoint of the line
float tempX = x + (size / 2) * sin(-angle);
float tempY = y + (size / 2) * cos(-angle);
stroke(0);
strokeWeight(1);
fill(140, 180);
rect(x, y, size, size); // circle
stroke(255, 0, 0);
line(x, y, tempX, tempY); // red line
}
