Why is this sketch so slow? Get() makes it slow

manu123

Hi

Can anyone tell me why this sketch runs so slow? The line with the "Get()" is the problem...

I tried different renderer (P2D, P3D...) but without success..

float  Angle = 0;

void setup() 
{
  size(600, 600,P3D ); 
  noSmooth();
}

void draw() {
  background(0);

  Angle += 0.8;

  // Draw something in the upper left corner (
  colorMode(HSB, 100);  
  pushMatrix();
  translate(7, 7);
  rotate(radians(Angle*34));
  Star5(0, 0, 9.5, 9.5, color(0, 100, 100), color(20, 100, 100), color(40, 100, 100), color(60, 100, 100), color(80, 100, 100), 100);
  popMatrix();


  colorMode(RGB, 255);
  noFill();

  // draw a rect (Pixel scan area)
  strokeWeight(1);
  stroke(255, 255);
  rect(-1, -1, 15, 15);



  int OffsetX = 50;
  int OffsetY = 50;
  int CellSize = 30;
  int GridWidth = 33;
  int CellRadius = 2;

  noStroke();

  // Scan Pixels in the upper left corner and draw matrix
  for (int yy = 0; yy < 13; yy++)
  {
    for (int xx = 0; xx < 13; xx++)
    {      
      color c = get(xx, yy); // THIS LINE MAKES THE WHOLE SKETCH VERY SLOW 
      //color c = color(xx*20,yy*20,0); // TO SEE THE DIFFERENCE... USE THIS LINE INSTEAD
      fill(c);
      rect(OffsetX + (xx * GridWidth), OffsetY + (yy * GridWidth),CellSize,CellSize,CellRadius);
    }
  } 
}


void Star5(float x1, float y1, float r1, float r2, color c1, color c2, color c3, color c4, color c5, int alpha) 
{
  // Draws a star
  noStroke();
  beginShape();
  fill(c1, alpha);
  vertex(x1+cos(radians(36*1))*r2, y1+sin(radians(36*1))*r2);
  vertex(x1+cos(radians(36*2))*r1, y1+sin(radians(36*2))*r1);
  fill(c2, alpha);
  vertex(x1+cos(radians(36*3))*r2, y1+sin(radians(36*3))*r2);
  vertex(x1+cos(radians(36*4))*r1, y1+sin(radians(36*4))*r1);
  fill(c3, alpha);
  vertex(x1+cos(radians(36*5))*r2, y1+sin(radians(36*5))*r2);
  vertex(x1+cos(radians(36*6))*r1, y1+sin(radians(36*6))*r1);
  fill(c4, alpha);
  vertex(x1+cos(radians(36*7))*r2, y1+sin(radians(36*7))*r2);
  vertex(x1+cos(radians(36*8))*r1, y1+sin(radians(36*8))*r1);
  fill(c5, alpha);
  vertex(x1+cos(radians(36*9))*r2, y1+sin(radians(36*9))*r2);
  vertex(x1+cos(radians(36*10))*r1, y1+sin(radians(36*10))*r1);
  endShape();
}

GoToLoop

Renderers P2D & P3D are OpenGL-based. Access to a specific pixel is slow for OpenGL AFAIK. 3:-O

Also, you should favor pixels[] over both get() & set() when possible. *-:)

manu123

Thank you so much!!

Heres my much faster sketch:

float  Angle = 0;

void setup() 
{
  size(600, 600,P3D ); 
  noSmooth();
}

void draw() {
  background(0);

  Angle += 0.8;

  // Draw something in the upper left corner (
  colorMode(HSB, 100);  
  pushMatrix();
  translate(7, 7);
  rotate(radians(Angle*34));
  Star5(0, 0, 9.5, 9.5, color(0, 100, 100), color(20, 100, 100), color(40, 100, 100), color(60, 100, 100), color(80, 100, 100), 100);
  popMatrix();


  colorMode(RGB, 255);
  noFill();

  // draw a rect (Pixel scan area)
  strokeWeight(1);
  stroke(255, 255);
  rect(-1, -1, 15, 15);



  int OffsetX = 50;
  int OffsetY = 50;
  int CellSize = 30;
  int GridWidth = 33;
  int CellRadius = 2;

  noStroke();

  // Scan Pixels in the upper left corner and draw matrix
  loadPixels();
  for (int yy = 0; yy < 13; yy++)
  {
    for (int xx = 0; xx < 13; xx++)
    {      
      color c = pixels[xx+(yy*height)];
      fill(c);
      rect(OffsetX + (xx * GridWidth), OffsetY + (yy * GridWidth),CellSize,CellSize,CellRadius);
    }
  } 
}


void Star5(float x1, float y1, float r1, float r2, color c1, color c2, color c3, color c4, color c5, int alpha) 
{
  // Draws a star
  noStroke();
  beginShape();
  fill(c1, alpha);
  vertex(x1+cos(radians(36*1))*r2, y1+sin(radians(36*1))*r2);
  vertex(x1+cos(radians(36*2))*r1, y1+sin(radians(36*2))*r1);
  fill(c2, alpha);
  vertex(x1+cos(radians(36*3))*r2, y1+sin(radians(36*3))*r2);
  vertex(x1+cos(radians(36*4))*r1, y1+sin(radians(36*4))*r1);
  fill(c3, alpha);
  vertex(x1+cos(radians(36*5))*r2, y1+sin(radians(36*5))*r2);
  vertex(x1+cos(radians(36*6))*r1, y1+sin(radians(36*6))*r1);
  fill(c4, alpha);
  vertex(x1+cos(radians(36*7))*r2, y1+sin(radians(36*7))*r2);
  vertex(x1+cos(radians(36*8))*r1, y1+sin(radians(36*8))*r1);
  fill(c5, alpha);
  vertex(x1+cos(radians(36*9))*r2, y1+sin(radians(36*9))*r2);
  vertex(x1+cos(radians(36*10))*r1, y1+sin(radians(36*10))*r1);
  endShape();
}