# Simple Sketch Lagging Despite Low Draw Time

**URL:** <https://discourse.processing.org/t/simple-sketch-lagging-despite-low-draw-time/38491>\
**Category:** Coding Questions\
**Created:** [August 26, 2022, 4:20am UTC](https://discourse.processing.org/t/simple-sketch-lagging-despite-low-draw-time/38491 "2022-08-26T04:20:28Z")\
**Posts on this page:** 4\
**Page:** 1

<div class="post-metadata">

**Author:** ![sudonym](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/sudonym/32/16845_2.png) [@sudonym](https://discourse.processing.org/u/sudonym)\
**Post date:** [August 26, 2022, 4:20am UTC](https://discourse.processing.org/t/simple-sketch-lagging-despite-low-draw-time/38491/1 "2022-08-26T04:20:29Z")

</div>

I have been using Processing for a while, and though my code can get pretty long it never lags. However, while working on this relatively simple sketch the display lags like crazy (~3-4fps).

This is the code for my sketch. I have timed the draw function and it typically takes \<10ms to run.

```auto
ArrayList<float[]> nodePos = new ArrayList<float[]>();
ArrayList<Integer> nodeSizes = new ArrayList<Integer>();
ArrayList<Float> nodePhases = new ArrayList<Float>();
ArrayList<Float> nodePeriods = new ArrayList<Float>();
ArrayList<Integer> nodeAmplitudes = new ArrayList<Integer>();

final int MAX_CIRCLE_SIZE = 10;
final int NUM_CIRCLES = 2;
final int[] posBounds = {-50,450};

void setup(){
  
  size(400,400);
  background(255);
  pixelDensity(2);
  strokeWeight(1);
  //frameRate(60);
  
  float[] pos= {0,0};
  
  for(int i=0; i<NUM_CIRCLES; i++){
    
    float[] newPos = new float[2];
    pos[0] = random(posBounds[0],posBounds[1]);
    pos[1] = random(posBounds[0],posBounds[1]);
    arrayCopy(pos,newPos);
    
    nodePos.add(newPos);
  }
  
  for(int i=0; i<nodePos.size();i ++){
    nodeSizes.add((Integer) (int)random(5,MAX_CIRCLE_SIZE));
    nodePhases.add(random(0,6.28));
    nodePeriods.add(random(1,2));
    nodeAmplitudes.add((Integer) (int)random(10,15));
  }
  
}

int start = 0;

void draw(){
  start = millis();
  background(255);
  int count = 0;
  for(int i=0; i<nodePos.size();i ++){
    for(int j=nodeSizes.get(i); j>0; j--){
      float amp = nodeAmplitudes.get(i) * (sin(millis()/1000)+1);
      circle(nodePos.get(i)[0],nodePos.get(i)[1], j*amp);
      count ++;
    }
  }
  print("Number of circles drawn: "+count+"\n");
  
  int end=millis();
  print("Time taken: "+(end-start)+"\n");
  
}

```

Sample output:

```auto
Number of circles drawn: 10
Time taken: 1
Number of circles drawn: 10
Time taken: 2
Number of circles drawn: 10
Time taken: 1
Number of circles drawn: 10
Time taken: 2
Number of circles drawn: 10
Time taken: 1

```

Can anyone help me figure out what is causing the lag?

I am using a macbook pro, with the M1 Pro chip.

---

<div class="post-metadata">

**Author:** ![scudly](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/scudly/32/5597_2.png) [@scudly](https://discourse.processing.org/u/scudly)\
**Post date:** [August 26, 2022, 4:57am UTC](https://discourse.processing.org/t/simple-sketch-lagging-despite-low-draw-time/38491/2 "2022-08-26T04:57:55Z")

</div>

millis() returns an integer. When you divide it by 1000, also an integer, you get only integer outputs.

In draw(), in your `sin(millis()/1000)` change it to `sin(millis()/1000.0)` to make it a float result.

---

<div class="post-metadata">

**Author:** ![sudonym](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/sudonym/32/16845_2.png) [@sudonym](https://discourse.processing.org/u/sudonym)\
**Post date:** [August 26, 2022, 5:08am UTC](https://discourse.processing.org/t/simple-sketch-lagging-despite-low-draw-time/38491/3 "2022-08-26T05:08:06Z")

</div>

LOL! Thanks. I missed that when debugging

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<div class="post-metadata">

**Author:** ![glv](https://yyz2.discourse-cdn.com/flex036/user_avatar/discourse.processing.org/glv/32/18785_2.png) [@glv](https://discourse.processing.org/u/glv)\
**Post date:** [August 26, 2022, 5:12am UTC](https://discourse.processing.org/t/simple-sketch-lagging-despite-low-draw-time/38491/4 "2022-08-26T05:12:57Z")

</div>

Hello @sudonym,

Consider something like this:

```auto
  float temp = sin(frameCount%400*(TAU/400)); // TAU = TWO_PI
  for(int i=0; i<nodePos.size();i ++){
    for(int j=nodeSizes.get(i); j>0; j--){
      float amp = nodeAmplitudes.get(i) * temp;
      circle(nodePos.get(i)[0], nodePos.get(i)[1], j*amp);
      count ++;
    }

```

I removed that _sin()_ calculation from the loop.

`:)`