You can create an array of spots, just as you would create an array of numbers in any procedural language.  The draw() method then simply iterates through this array, drawing each spot in turn. The class Spot remains unchanged.

Quote:

Hey Dialogic,

I'm not completely sure what you mean by 'continue to draw spots by the void draw command.' Any code inside of draw(){} will be executed repeatedly until you exit the program. If you want a single Spot drawn every frame at a random position, you'll need to change the Spot's position every frame.

One way to do this would be to manually set the x and y values of your Spot every frame. This kind of defeats the purpose of encapsulating values in your class.
Code:

void draw(){
  spot.x = random(0, width);
  spot.y = random(0, height);
  spot.display();
}
 

Instead, you could define a way for your Spot to move inside the Spot class, and simply tell the Spot to move every frame. Since the Spot knows how it moves about, you don't have to worry about the details of how it gets to its new position. In the future, you'll be able to create a lot of Spots (like in the array example) and never worry about there position values, instead just telling them each to move() and display().

Code:

//in your Spot class, add a move method
class Spot{
...

void move(){
  x = random(0,width);
  y = random(0,height);
}

...
}

//in your draw() function, call the move method

void draw(){
  spot.move(); //this is our new method
  spot.display();
}
 

Have fun experimenting with different implementations of the move() function. Try adding (or subtracting) one to the x value on every move, or changing the range the Spot bounces around in.

You shouldn't have to use noLoop() to stop drawing anchors. The reason it keeps adding them is because you're instantiating them in the draw() function.

Move all your
ancX = new Anchor(xpos, ypos);

statements to the setup() function.

As for the rope, it doesn't work because you have noLoop(). Without the loop, it will never get new mouse coordinates. and redraw the line to whereever the mouse is.
For the rope, you should move it's instantiation to setup() just like the anchors.  Then, in your draw() function you sill have rp.display(), but what happens here? it simply draws the line, it never updates the x2,y2 coords to mouseX/mouseY.  you can update those in the display function, or create an .update() function and run both
rp.update()
rp.display() in draw()

Hope that makes sense.

Oh, and maybe you want to add a
background(255);
to the top of your draw() function.

alecks wrote on Sep 25^th, 2008, 8:55pm:



Could you perhaps clarify the update function or how to make it I've got a build that "works" in the sense that it draws an anchor and draws a line from-mouse-to-anchor but it does so every millisecond. That is to say, every frame it places the anchor somewhere else. In a different build, it wouldn't redraw every frame, and the mouse-line worked as intended, but adding another anchor (anc2) simply draws them on top of eachother.

Any help would be greatly appreciated:

Code:

//Gravity Clone, Cassidy Liston 9-23-08

//Class Anchor has 6 children.

Anchor anc1;
Anchor anc2;
Anchor anc3;
Anchor anc4;
Anchor anc5;
Anchor anc6;

Rope rp;  // A single line that draws from nearest anchor to mouse.


PImage anchor;  //We have a sprite that will be implemented later.

float xpos;
float ypos;   //I am unsure if I need these.

void setup() 
{
 
  size(240,480);
  
  
  anc1 = new Anchor(xpos, ypos); 
  rp = new Rope(xpos, ypos, mouseX, mouseY);
 
  anc2 = new Anchor(xpos, ypos);

  anc3 = new Anchor(xpos, ypos);
  anc4 = new Anchor(xpos, ypos);
  anc5 = new Anchor(xpos, ypos);
  anc6 = new Anchor(xpos, ypos);
  
}

void draw() 
{ 
  xpos = random(0,240);
  ypos = random(20,450);
  background (110, 110, 120);
  stroke(25,30,0); 
  line (0, 470, 240, 470); //this is the "ground"
  
  anc1.display ();
  rp.display ();
   
 // anc2.display ();  //This anchor draws over the first one...
/*  The rest is disabled until I can get two separate Anchors.
  anc3.display ();
  
  xpos = random(10,200);
  ypos = random(20,440);
  
  anc4.display ();
  
  xpos = random(10,200);
  ypos = random(20,440);
  
  anc5.display ();
  
  xpos = random(10,200);
  ypos = random(20,440);
  
  anc6.display ();
  
  frameRate(10);
*/
}

class Anchor {

float x, y;
  
  Anchor (float x, float y) {
    x = xpos; 
    y = ypos;  
  }
  
  void display () {
    anchor = loadImage("anchorgrn.gif");
    image (anchor, xpos, ypos);
   
  }
}

class Rope {
  
  float x1, y1, x2, y2;
  
  Rope (float x1, float y1, float x2, float y2) {
    x1 = xpos;
    y1 = xpos;
    x2 = mouseX;
    y2 = mouseY;
  }
  
  void display () {
    stroke (200);
    line((xpos + 7), (ypos + 7), mouseX, mouseY);
    
  }
}