Hello,

I'm still very new to Processing, so please forgive me for asking what I'm sure is a silly question.

I've been working on a sketch that takes the red, green and blue values from 16 points in an image. The 16 points are equally spaced throughout the image. I have then used the RGB values to form 16 XYZ vertex points. The idea is that I get a squiggly line on a blank canvas.

When I do the excercise long-hand, filling in the numerical values manually, everything is fine. But I've tried to create arrays for the RGB values, and now when the vertex draws I only get points - no squiggly line.

The mistake is probably simple, but I'm having difficulty finding it. If anyone can help, I'd be extremely grateful.

Thanks, Andy







PImage ethno;

float [] redValue = new float[16];
float [] greenValue = new float[16];
float [] blueValue = new float[16];



void setup() {
  size(640,478, P3D);
  ethno = loadImage("1-17_04_wed.JPG");

}


void draw() {
  background (255);
  stroke(0);
  strokeWeight(5);
  smooth();
  //image(ethno, 0, 0);   


  for (int i =80; i<width; i+=160) {
    for(int j= 60; j<height; j+= 120) {

      color c = ethno.get (i,j);

      float valueR = red(c);
      //println("red = " + valueR);

      float valueG = green(c);
      //println("green = " + valueG);

      float valueB = blue(c);
      //println("blue = " + valueB);

      for(int k =0; k < 16; k++) {
        redValue[k] = valueR;
        greenValue[k] = valueG;
        blueValue[k] = valueB;
       
        beginShape();
        vertex(redValue[k], greenValue[k], blueValue[k]);
       endShape(CLOSE);
      }
    }
  }
}

Hello,

I am very new to Processing, so please forgive what I'm sure will be ignorance to the point of stupidity. So far I have found this forum extremely helpful, but this will be my first post.

I am writing a sketch that will gather the RGB values from a set range of pixels from a loaded image - this is where I have gotten to.
The next step is to convert the RGB values to XYZ co-ordinates in a 3D environment with a vertex shape connecting the points.

My question is, theoretically speaking, how do I save the RGB values, then load them to be read (by something?) in a new 3D sketch.

I'm looking at arrays, but using them seems to assume a knowledge that I don't have yet.

If you know of any relevant tutorials, or any other pointers, I'd be extremely grateful.

Best wishes,
Andy