lightmeter/positionfinder/positionfinder.pde

/**
 * Simple Read
 * 
 * Read data from the serial port and change the color of a rectangle
 * when a switch connected to a Wiring or Arduino board is pressed and released.
 * This example works with the Wiring / Arduino program that follows below.
 */


import processing.serial.*;

Serial myPort;  // Create object from Serial class
int analoglow;      // Data received from the serial port
int analoghigh;      // Data received from the serial port
int newdata=0;

int screenwidth=1024;
int screenheight=768;

int xstart;
int ystart;
int xend;
int yend;

int testpart=1; //0=finished, 1=left, 2=right, 3=up, 4=down

int readingA=0;
int readingB=0;

int stopsize=30; //minimum rect height and width
int minvaluedistance=50; //how far analog values need to be apart

void setup() 
{
  size(1024, 768);
  
  xstart=0;
  ystart=0;
  xend=width;
  yend=height;
  
  printArray(Serial.list());
  //String portName = Serial.list()[35];
  String portName="/dev/ttyUSB0";
  myPort = new Serial(this, portName, 115200);
}

void draw()
{
  if ( myPort.available() > 0) {  // If data is available,
    String inBuffer = trim(myPort.readString());   
    if (inBuffer != null) {
      //println(inBuffer);
      String[] list = split(inBuffer, ';');
      //print("list=");
      //printArray(list);
      if (list.length>=2){
        analoglow=parseInt(list[0]);
        analoghigh=parseInt(list[1]);
        //print("->");
        //print(analoglow);
        //print(",");
        //println(analoghigh);
        newdata+=1;
      }
    }
  }
  
  
  
  
  
  if (newdata>=3){ //wait some reading
    newdata=0; //reset counter
    
    int reading=analoglow; //use only one analog value
    
    switch(testpart){
      case 1: //left
        readingA=reading;
        print("A="); println(readingA);
        testpart++; //next part
        break;
      case 2: //right
        readingB=reading;
        print("B="); println(readingB);
        //apply to positions
        if (readingA>readingB+minvaluedistance){ //left part was brighter
          xend=xstart+(xend-xstart)/2;
          println("Left");
          testpart++; //next part
        }else if(readingB>readingA+minvaluedistance){
          xstart=xstart+(xend-xstart)/2;
          println("Right");
          testpart++; //next part
        }else{
          print("No definitely better part found: ");
          print(readingA); print(" vs. "); println(readingB);
          float randommove=random(-(xstart-xend)/20,(xstart-xend)/20);
          while (abs(randommove)<1){
            randommove*=2;
          }
          xstart+=randommove; //move rect a bit
          xend+=randommove;
          testpart--;
        }
        break;
      case 3: //up
        readingA=reading;
        print("A="); println(readingA);
        testpart++; //next part
        break;
      case 4: //down
        readingB=reading;
        print("B="); println(readingB);
        if (readingA>readingB+minvaluedistance){ //upper part was brighter
          yend=ystart+(yend-ystart)/2;
          println("Up");
          testpart++; //next part
        }else if(readingB>readingA+minvaluedistance){
          ystart=ystart+(yend-ystart)/2;
          println("Down");
          testpart++; //next part
        }else{
          print("No definitely better part found: ");
          print(readingA); print(" vs. "); println(readingB);
          float randommove=random(-(ystart-yend)/20,(ystart-yend)/20);
          while (abs(randommove)<1){
            randommove*=2;
          }
          ystart+=randommove; //move rect a bit
          yend+=randommove; //move rect a bit
          testpart--;
        }
        break;
    }
    
    
    if (testpart>4){
      testpart=1;
    }
    
    print("Testing Part:");
    println(testpart);
  }
  
  if (yend-ystart<=stopsize){
    testpart=0; //stop
  }
  
  
  
  background(0);             // Set background to white
  clear();
  fill(255);
  rectMode(CORNERS);
  switch(testpart){ //draw current segment
    case 1: //left
      rect(xstart, ystart, xstart+(xend-xstart)/2, yend);
      break;
    case 2: //right
      rect(xstart+(xend-xstart)/2, ystart, xend, yend);
      break;
    case 3: //up
      rect(xstart, ystart, xend, ystart+(yend-ystart)/2);
      break;
    case 4: //down
      rect(xstart, ystart+(yend-ystart)/2, xend, yend);
      break;
  }
  
  
    
   
  
}