Updating colorfill

Dino_van_Deijzen

Hi team,

I have an issue regarding the updating of the colorfill when using a beginShape() / endShape() function.

I have a plane ( x & y grid) which has a colorfill that changes during time (updates). It doesnt update though. When i use random(255) it does change, though when using a variable it only takes the1st (or last). the colorgrid (static looks as such:

Do i need to include a command that allows updtating fill colors with changing values on the x-y grid. code with example of variable that changes the grid ( in real it will be an array with data for each gridpoint (vertex) that refreshes ech iteration):

void setup() {
  size(900, 700, P3D);
  //noStroke();
}

void draw() {
  background(0);
  translate(width/4, height/1.2);

 int fillvariable= 0;
  
 for(int w=0; w< 400; w+= 25){
   for(int h=0; h> -400; h-= 25){
  
beginShape(QUADS);
  normal(0, 0, 1);
  fill(w/2, h/2, 200);
  vertex(w, h);
  
   fill(fillvariable, h/2, 200);
  vertex(w+25, h);
  
  fill(w/2, h/2, 200);
  vertex(w+25, h-25);
  
   fill(w/2, h/2, 200);
  vertex(w, h-25);
  endShape();
  
  
   fillvariable += 20;
   if( fillvariable >255)  {  fillvariable=0; }
   println(fillvariable);
   
  }
 }
}

Is this way of filling a grid the smartest way (basically its making an colored isosurface)? Might be that this way takes much memory or cpu in the way its looping. I am trying to read into shaders and how + when to use them, but at the beginning of the gpu to cpu difference and how processing uses such.

Lord_of_the_Galaxy

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Dino_van_Deijzen

Dear L_o_t_Galaxy: Did my best to adjust it in the correct format. hope its readable in this way. warmest regards,

Dino

Lord_of_the_Galaxy

OK.
Did you mean to declare your fillvariable inside draw? If so, your code cannot be dynamic.

Dino_van_Deijzen

The variable itself is dynamically updated by a for loop that opens an array of data that will influence the color and make up the isosurface. I think the only way to do so is to hav ethem both in draw() .

Not yet sure how to solve this using another approach in order to achieve a dynamically update color.

Lord_of_the_Galaxy

What exactly was your question anyway?

Dino_van_Deijzen

Dear L_o_t_Galaxy.

The question : How can i upate the fill color data in a BeginShape() ......endShape() in which the pixels are colored by the local vertex points?

Secondly is there a better aproach (it might be the wrong way trying to color the pixels like this)

beginShape(QUADS);
  normal(0, 0, 1);
  fill( Variable);
  vertex(w, h);
   
   fill( Variable);
  vertex(w+25, h);
   
  fill(255, 255, 200);
  vertex(w+25, h-25);
   
   fill(255, 255, 200);
  vertex(w, h-25);
  endShape();

seems only a "random(255)" will dynamically change the values. The goal is to drive the fill() command by data comming from an array that changes each iteration.

warmest regards,

Dino

Lord_of_the_Galaxy

No, as long as your variable is dynamically changing, the color also changes. However, note that only one edge of the square is affected by the "Variable".

Dino_van_Deijzen

Dear L_o_t_Galaxy, It gave me the insight i needed , from here i can build further to include the array's.

int fillvariable= 0;

 void setup() {
   size(900, 700, P3D);
   //noStroke();
 }

 void draw() {
   background(0);
   translate(width/4, height/1.2);

  for(int w=0; w< 400; w+= 50){
    for(int h=0; h> -400; h-= 50){

 beginShape(QUADS);
   normal(0, 0, 1);
   fill(fillvariable);
   vertex(w, h);

    fill(fillvariable);
   vertex(w+25, h);

   fill(0);
   vertex(w+25, h-25);

    fill(0);
   vertex(w, h-25);
   endShape();

    fillvariable += 20;
    if( fillvariable >255)  {
      fillvariable=0;
    }
    println(fillvariable);

   }
  }
 }

much much apreciated

Lord_of_the_Galaxy

Yes, that's what I meant. And that's why I asked why you declared your variable in draw().