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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

HTML

              
                <button id="next">Next</button>
<button id="all">All</button>
<button id="reset">Reset</button>
<canvas id="canvas"></canvas>

              
            
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CSS

              
                #canvas {
  display: block;
  border: 1px solid gray;
}

              
            
!

JS

              
                (function() {

  // Class to generate a random masonry layout, using a square grid as base
  class Grid {

    // The constructor receives all the following parameters:
    // - gridSize: The size (width and height) for smallest unit size
    // - gridColumns: Number of columns for the grid (width = gridColumns * gridSize)
    // - gridRows: Number of rows for the grid (height = gridRows * gridSize)
    // - gridMin: Min width and height limits for rectangles (in grid units)
    constructor(gridSize, gridColumns, gridRows, gridMin) {
      this.gridSize = gridSize
      this.gridColumns = gridColumns
      this.gridRows = gridRows
      this.gridMin = gridMin
      this.rects = []
      this.currentRects = [{ x: 0, y: 0, w: this.gridColumns, h: this.gridRows }]
    }

    // Takes the first rectangle on the list, and divides it in 2 more rectangles if possible
    splitCurrentRect () {
      if (this.currentRects.length) {
        const currentRect = this.currentRects.shift()
        const cutVertical = currentRect.w > currentRect.h
        const cutSide = cutVertical ? currentRect.w : currentRect.h
        const cutSize = cutVertical ? 'w' : 'h'
        const cutAxis = cutVertical ? 'x' : 'y'
        if (cutSide > this.gridMin * 2) {
          const rect1Size = randomInRange(this.gridMin, cutSide - this.gridMin)
          const rect1 = Object.assign({}, currentRect, { [cutSize]: rect1Size })
          const rect2 = Object.assign({}, currentRect, { [cutAxis]: currentRect[cutAxis] + rect1Size, [cutSize]: currentRect[cutSize] - rect1Size })
          drawRect(rect1)
          drawRect(rect2)
          this.currentRects.push(rect1, rect2)
        }
        else {
          this.rects.push(currentRect)
          this.splitCurrentRect()
        }
      } else {
        console.log('end')
      }
    }

    // Call `splitCurrentRect` until there is no more rectangles on the list
    // Then return the list of rectangles
    generateRects () {
      while (this.currentRects.length) {
        this.splitCurrentRect()
      }
      return this.rects
    }
  }

  // Generate a random integer in the range provided
  function randomInRange (min, max) {
    return Math.floor(Math.random() * (max - min + 1)) + min
  }

  // Generate a random color
  function randomColor () {
    const color = [0, 0, 0]
    for (let i = 0; i <= 2; i++) {
      if (Math.random() < 0.66666)
        color[i] = 32 + parseInt(Math.random() * 192)
    }
    return 'rgb(' + color[0] + ',' + color[1] + ',' + color[2] + ')'
  }

  // Draw a rect in the canvas
  function drawRect (r) {
    ctx.fillStyle = r.color || randomColor()
    ctx.fillRect(r.x * gridSize, r.y * gridSize, r.w * gridSize, r.h * gridSize)
  }

  // Clear the canvas
  function clearCanvas () {
    ctx.fillStyle = 'white'
    ctx.fillRect(0, 0, width, height)
  }

  // Variables and settings
  const next = document.getElementById('next')
  const all = document.getElementById('all')
  const reset = document.getElementById('reset')
  const canvas = document.getElementById('canvas')
  const ctx = canvas.getContext('2d')
  const gridSize = 50
  const gridColumns = 20
  const gridRows = 10
  const gridMin = 3
  const width = gridSize * gridColumns
  const height = gridSize * gridRows
  canvas.width = width
  canvas.height = height

  // Start a new grid
  let grid
  function start () {
    grid = new Grid(gridSize, gridColumns, gridRows, gridMin)
  }
  start()

  // Listen for click on buttons and run the algoritm

  next.addEventListener('click', () => {
    grid.splitCurrentRect()
  })

  all.addEventListener('click', () => {
    grid.generateRects()
  })

  reset.addEventListener('click', () => {
    clearCanvas()
    start()
  })

})()

              
            
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