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Index › Programming Questions & Help › Syntax Questions › Help with text()
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Help with text() (Read 508 times)
Matt Witmer
Help with text()
May 25th, 2009, 9:43am  
I am trying to display a double which is coming from my Arduino but everytime the variable updates the old value still stays on the screen.

Code:
import cc.arduino.*;
import processing.serial.*;

double temperature;
Arduino arduino;
int tempPin = 0;

PFont myFont;

void setup () {
  size(600, 200);
  println(Arduino.list());
  arduino = new Arduino(this, Arduino.list()[0]);
  arduino.pinMode(tempPin, Arduino.INPUT);
  myFont = createFont("HelveticaNeue", 48);
  textFont(myFont);
}

void draw(){
  if(arduino.analogRead(tempPin)==0)
  {
    System.out.println("Loading..");
    delay(5000);
  }
  float temperature = Thermister(arduino.analogRead(tempPin));
  text("Temperature: " + temperature, 35, 185);
}

float Thermister(int RawADC) {
 float Temp;
 Temp = log(((10240000/RawADC) - 10000));
 Temp = 1 / (0.001129148 + (0.000234125 * Temp) + (0.0000000876741 * Temp * Temp * Temp));
 Temp = Temp - 273.15;            // Convert Kelvin to Celcius
 Temp = (Temp * 9.0)/ 5.0 + 32.0; // Convert Celcius to Fahrenheit
 if ( Temp > 0 )
   {return float(floor(Temp * 100))/100;}
 else
   {return float(ceil(Temp * 100))/100;}
}


I would post a screenshot, but I don't have enough posts.

Anyone know why this would be?

Thanks,
Matt
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Quark
Re: Help with text()
Reply #1 - May 25th, 2009, 10:22am  
At the being of the draw() method you need to clear the screen before drawing text etc.

Place the following lines at the beginning of the draw function and see what happens. I think thiis will solve your problem. Smiley


Code:

void draw() {
   background(0); // black background
   fill(0,255,0);   // green text
   noStroke();
   // your code
}
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WWW  
Matt Witmer
Re: Help with text()
Reply #2 - May 25th, 2009, 10:26am  
Fantastic. Thanks for your help.
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