Category: Young

For this recitation, I intended to utilize the camera and pixel function that I learned in class and the infrared distance sensor to make a device, which can change the resolution of the camera by changing the distance that the infrared sensor senses.

I met some challenges in coding this program. The range of the infrared distance sensor that I used was 20 cm to 150 cm. In the first trial, I set the beginning number of the mapped range as 0 and it turned out that there was an error in the code. When I pressed the run button, only black canvas showed on my screen. Therefore, I changed the beginning range from 0 to 1 and this made the camera interface appeared on the canvas. The interface of the camera appeared unclear at first, after strengthening each connecting part,  the device finally produced the effect I wanted. When the user came close to the infrared sensor, the ellipse on the interface would become smaller, producing the effect that the camera became clearer. And when the distance that the sensor got became larger, the radius of the ellipse would increase which made the camera vague again.

After finish reading “Computer Vision for Artist and Designers”, I contemplated more about the “algorithm communication”. This is exactly how those brilliant works that made by computers come from. I also used this technology in my project. In fact, the code that I have written until now can all be concluded as algorithm communication, since they all rely on simple codes to produce complicated effects.

Code:

Processing

// IMA NYU Shanghai
// Interaction Lab
// This code receives one value from Arduino to Processing

import processing.serial.*;
import processing.video.*;
Capture cam;
int Size = 10;

Serial myPort;
int valueFromArduino;
int PORT_INDEX=5;

void setup() {
size(640, 480);
cam = new Capture (this, 640, 480);
cam.start();

printArray(Serial.list());
// this prints out the list of all available serial ports on your computer.

myPort = new Serial(this, Serial.list()[ PORT_INDEX ], 9600);
// WARNING!
// You will definitely get an error here.
// Change the PORT_INDEX to 0 and try running it again.
// And then, check the list of the ports,
// find the port “/dev/cu.usbmodem—-” or “/dev/tty.usbmodem—-”
// and replace PORT_INDEX above with the index number of the port.
}

void draw() {
if (cam.available()) {
cam.read();
cam.loadPixels();
}
while ( myPort.available() > 0) {
valueFromArduino = myPort.read();
}
int a = int(map (valueFromArduino,200,1500,1,10));
for (int y=0; y<cam.height; y+=a) {
for (int x=0; x<cam.width; x+=a) {
int i= y*cam.width+x;
fill( cam.pixels[i] );
noStroke();
ellipse(x, y, a, a);
}
}
//image(cam,0,0,width,height);
cam.updatePixels();

// to read the value from the Arduino

println(valueFromArduino);//This prints out the values from Arduino
}

Arduino

// IMA NYU Shanghai
// Interaction Lab
// This code sends one value from Arduino to Processing

void setup() {
Serial.begin(9600);
pinMode(pin, INPUT);
}

void loop() {
Serial.write(sensorValue);
uint16_t sensorValue = analogRead (pin);
double distance = get_IR (sensorValue);
Serial.println (sensorValue);
Serial.println (” cm”);
Serial.println ();
delay (500);
delay(10);
double get_IR (uint16_t sensorValue) {
if (sensorValue < 16) sensorValue = 16;
return 2076.0 / (sensorValue – 11.0);
}

For this recitation, I chose Object-Oriented Programming workshop because I will do a game as my final project and this workshop could benefit me the most in my opinion.

Based on what I learned in the class on Thursday, I made some improvements and interaction function to the code.

I changed the interaction form with the mouse from producing more balls to make the balls disappear. Since two kinds of interaction were impossible to perform at the same time, so I deleted the original code and set the number of the balls in the setup loop as 20. In my first trial, I directly put an “if” function, saying that the ball which the mouse clicked on would disappear. However, my alternation didn’t work since the program couldn’t recognize the radius of each different ball. And I realized that to eventually achieve my purpose, another attribute was also needed in the Balls function to represent its radius. And when the position where the mouse clicks falls in the area that is within the radius of that circle, the circle would disappear.

I added the interaction with the keyboard in order to make it more interactive. Since I kept the part of the code of bounce, the balls would still move in the adverse direction when touching the rim of the canvas. Addition to that, users could also control the movement of the balls by clicking on the direction keys. However, when I pressed one of the direction keys, although all the balls will generally move in the intended direction, some balls will ignore the bounce code and disappear at the rim of the canvas. And I wondered why this would happen.

Code:

ArrayList<Ball> balls = new ArrayList<Ball>();

void setup() {
size(500, 600);
noStroke();
balls = new ArrayList<Ball>();
for (int i=0; i<20; i++) {
balls.add(new Ball(width/2, height/2, random(30,75)));
}

}
void draw() {
background(255);
for (int i=0; i<balls.size(); i++) {
Ball b = balls.get(i);
b.move();
b.bounce();
b.display();
if (key==CODED) {
if (keyCode==UP) {
b.y–;
}
if (keyCode==DOWN) {
b.y++;
}
if (keyCode==LEFT) {
b.x–;
}
if (keyCode==DOWN) {
b.x++;
}
}
}
if (mousePressed) {
for (int i=0; i<balls.size(); i++) {
Ball b = balls.get(i);
float diameter=b.w;
float dx = abs(mouseX-b.x);
float dy = abs(mouseX-b.y);
float distance= sqrt(sq(dx)+sq(dy));
if (distance<= diameter) {
balls.remove(i);
}
}
}
}

ArrayList<Ball> balls = new ArrayList<Ball>();

void setup() {
size(500, 600);
noStroke();
balls = new ArrayList<Ball>();
for (int i=0; i<20; i++) {
balls.add(new Ball(width/2, height/2, random(30,75)));
}

}
void draw() {
background(255);
for (int i=0; i<balls.size(); i++) {
Ball b = balls.get(i);
b.move();
b.bounce();
b.display();
if (key==CODED) {
if (keyCode==UP) {
b.y–;
}
if (keyCode==DOWN) {
b.y++;
}
if (keyCode==LEFT) {
b.x–;
}
if (keyCode==DOWN) {
b.x++;
}
}
}
if (mousePressed) {
for (int i=0; i<balls.size(); i++) {
Ball b = balls.get(i);
float diameter=b.w;
float dx = abs(mouseX-b.x);
float dy = abs(mouseX-b.y);
float distance= sqrt(sq(dx)+sq(dy));
if (distance<= diameter) {
balls.remove(i);
}
}
}
}