Snippet Zone

Divide Rectangle Into Smaller Rectangles

const rand = num => ~~(Math.random() * num)

```
 
```
```
let rectNum = 2 + rand(10)
```
```
let rectCount = 0
```
```
 
```

document.body.appendChild(document.createElement('div')).innerText =

```
  'click anywhere to regenerate'
```
```
 
```
```
function reset() {
```

  ;[...document.querySelectorAll('.rect')].forEach(rect => rect.remove())

```
  rectNum = 2 + rand(10)
```
```
  rectCount = 0
```
```
  newRect(300, 300, 50, 50)
```
```
}
```
```
reset()
```
```
onpointerup = reset
```
```
 
```
```
function newRect(w, h, xp, yp) {
```

  const rect = document.body.appendChild(document.createElement('div'))

```
 
```
```
  rect.classList.add('rect')
```
```
  rectCount++
```
```
 
```
```
  Object.assign(rect.style, {
```
```
    position: 'absolute',
```
```
    left: `${xp}px`,
```
```
    top: `${yp}px`,
```
```
    width: `${w}px`,
```
```
    height: `${h}px`,
```
```
    outline: `1px solid black`,
```
```
  })
```
```
 
```
```
  const props = {
```
```
    x: xp,
```
```
    y: yp,
```
```
    height: h,
```
```
    width: w,
```
```
    seed: rand(3),
```
```
    divide() {
```

      const div = 2 + rand(5 * Math.random() * Math.random())

```
      if (rand(2) == rand(2)) {
```

        const newHeight = this.height / div

```
 
```

        newRect(this.width, this.height - newHeight, this.x, this.y)

        newRect(this.width, newHeight, this.x, this.y + this.height - newHeight)

```
      } else {
```
```
        const newWidth = w / div
```

        newRect(this.width - newWidth, this.height, this.x, this.y)

        newRect(newWidth, this.height, this.x + this.width - newWidth, this.y)

```
      }
```
```
      rect.remove()
```
```
    },
```
```
  }
```
```
  window.requestAnimationFrame(() => {
```
```
    if (rectCount < rectNum) {
```
```
      props.divide()
```
```
    } else {
```
```
      console.log('DONE!')
```
```
    }
```
```
  })
```
```
}
```

This snippet comes to mind from time to time – one easy way to divide a rectangle into smaller rectangles- I actually went back and looked it up as it was an answer to a student question from 2006. The original one was written in ActionScript 2. Have a look:

```
var wormNum:Number = 123;
```
```
var wormCount:Number = 0;
```
```
newWorm(400, 400, 0, 0);
```
```
this.onEnterFrame = function() {
```
```
	if (wormCount < wormNum) {
```
```
		for (var props:String in this) {
```
```
			if (this[props]._x != undefined) {
```
```
				this[props].divide();
```
```
			}
```
```
		}
```
```
	}
```
```
};
```
```
function newWorm(w, h, xp, yp) {
```

	var currWorm:MovieClip = this.createEmptyMovieClip("box"+wormCount, this.getNextHighestDepth());

```
	wormCount++;
```
```
	box(w, h, currWorm, random(0xFFFFFF));
```
```
	currWorm._x = xp;
```
```
	currWorm._y = yp;
```
```
	currWorm.seed = random(3);
```
```
	currWorm.divide = function() {
```

		var div = random(4)+(1+Math.random()*1);

```
		if (random(2) == random(2)) {
```
```
			// divide vertically
```
```
			var nh:Number = this._height/div;
```

			newWorm(this._width, this._height-nh, this._x, this._y);

			newWorm(this._width, nh, this._x, this._y+this._height-nh);

```
		} else {
```
```
			// divide horizonatlly
```
```
			var nw:Number = this._width/div;
```

			newWorm(this._width-nw, this._height, this._x, this._y);

			newWorm(nw, this._height, this._x+this._width-nw, this._y);

```
		}
```
```
		this.removeMovieClip();
```
```
	};
```
```
}
```

function box(w:Number, h:Number, mc:MovieClip, col:Number):Void {

```
	with (mc) {
```
```
		lineStyle(0, 0, 20);
```
```
		beginFill(col, 10);
```
```
		moveTo(0, 0);
```
```
		lineTo(w, 0);
```
```
		lineTo(w, h);
```
```
		lineTo(0, h);
```
```
		endFill();
```
```
	}
```
```
}
```

Don’t remember why I called them worms instead of rectangles, some AS2 types floating around…

December 28, 2022

// graphics // humor // javascript // math // oldschool // random // speedcoding

Divide Rectangle Into Smaller Rectangles

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