Thanks for response....

what would be the way of doing this using vectors? Can I use the function PVector.sub(p1.pos, p2.pos)?

Done the particles, just need to initiate springs and create a thread class I reckon..........

thanks for your advise

// IMPORT EXTERNAL LIBRARIES

import peasy.*;               // the camera library
import processing.opengl.*;   // openGL library

/*------------------------------------------------------------------
 *** GLOBAL VARIABLES ***
 ------------------------------------------------------------------*/

//----------declare the camera
PeasyCam  theCamera;

//----------declare the environment
int boundingBox = 600;

//----------declare the mid particles
int numMidParticles = 8;

//----------declare particle array
Particle[] particleList;


/*------------------------------------------------------------------
 *** GLOBAL SETUP ***
 ------------------------------------------------------------------*/

void setup() {

  //----------general
  size(900, 900, OPENGL);
  smooth();

  //----------make the camera
  theCamera = new PeasyCam(this, boundingBox*2);
  theCamera.lookAt(boundingBox/2, boundingBox/2, boundingBox/2);

  //----------make the particle array
  particleList = new Particle[11];

  //----------make the end particles
  // make vectors
  PVector tmpPos1 = new PVector(random(boundingBox), random(boundingBox), 0);
  PVector tmpPos2 = new PVector(random(boundingBox), random(boundingBox), 600);
  // make end particles
  Particle tmpPart1 = new Particle(tmpPos1);
  Particle tmpPart2 = new Particle(tmpPos2);

  particleList[0] = tmpPart1;
  particleList[10] = tmpPart2;



  //----------make the mid particles
  for (int i = 1; i < numMidParticles+2; i++) {
    // sub end vectors
    PVector vecBetween = PVector.sub(tmpPos1, tmpPos2);
    // divide vecBetween by 10
    vecBetween.div(10);
    // scale vecBetween by i
    PVector vecScale = PVector.mult(vecBetween, i);
    // add new vector to end vector
    PVector newVec = PVector.add(vecScale, tmpPos2);
    // create new Particle at newVec
    Particle tmpPartMid = new Particle(newVec);

    particleList[i] = tmpPartMid;
  }
}


/*------------------------------------------------------------------
 *** GLOBAL CONTINUOUS DRAW ***
 ------------------------------------------------------------------*/

void draw() {

  background(255);

  particleList[0].showMe();
  particleList[10].showMe();

  for (int i = 1; i < numMidParticles+2; i++) {
    particleList[i].showMe();
  }

  drawBox();
}



void drawBox() {
  stroke(100);
  strokeWeight(1);
  noFill();
  pushMatrix();
  translate(boundingBox/2, boundingBox/2, boundingBox/2);
  box(boundingBox);
  popMatrix();
}

Yes you can use PVector to store the points see below.

1. int nbrPoints = 10;
2. PVector[] chain;
3. 
   
4. void setup(){
5.   chain = new PVector[nbrPoints];
6.   chain[0] = new PVector(-12, -23, 34);
7.   chain[nbrPoints - 1] = new PVector(58, 87, -26);
8.  
9.   PVector gap = PVector.sub(chain[nbrPoints -1], chain[0]);
10.   gap.div(nbrPoints - 1);
11.   // ignore first and last already done
12.   for(int i = 1; i < chain.length - 1; i++){
13.     chain[i] = PVector.mult(gap, i);
14.     chain[i].add(chain[0]);
15.   }
16.   // display points
17.   for(int i = 0; i < chain.length; i++){
18.     println(chain[i]);
19.   }
20. }