cssAudio - Activefile-genericCSS - ActiveGeneric - ActiveHTML - ActiveImage - ActiveJS - ActiveSVG - ActiveText - Activefile-genericVideo - ActiveLovehtmlicon-new-collectionicon-personicon-teamlog-outoctocatpop-outspinnerstartv

Pen Settings

CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

Any URL's added here will be added as <link>s in order, and before the CSS in the editor. If you link to another Pen, it will include the CSS from that Pen. If the preprocessor matches, it will attempt to combine them before processing.

+ add another resource

Looking for quick-add? Try the external resource search, it's quicker and gives you access to the most recent version of thousands of libraries. ☝️

You're using npm packages, so we've auto-selected Babel for you here, which we require to process imports and make it all work. If you need to use a different JavaScript preprocessor, remove the packages in the npm tab.

Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

+ add another resource

Looking for quick-add? Try the external resource search, it's quicker and gives you access to the most recent version of thousands of libraries. ☝️

Use npm Packages

We can make npm packages available for you to use in your JavaScript. We use webpack to prepare them and make them available to import. We'll also process your JavaScript with Babel.

⚠️ This feature can only be used by logged in users.

Code Indentation

     

Save Automatically?

If active, Pens will autosave every 30 seconds after being saved once.

Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

            
              <main class="app-container">
  
  <h1>VueJS + HTML5 Canvas</h1>
  <span class="sub">Image upload, resize, crop, and base64 converter</span>
  
  <div id="app">
    <image-uploader 
      width="300px" 
      height="200px">
    </image-uploader>
    <section class="text-area-section">
      <textarea 
        v-model="sharedData.imageData">
      </textarea>
    </section>
  </div>
</main>

<!-- -->
<script type="text/x-template" id="image-uploader-template">
<div class="image-input__container image-uploader" 
	v-bind:style="containerStyles" 
  v-bind:class="{ 'image-loaded': isImageLoaded }">

    <!-- Hidden input we use to access file contents -->
    <form class="image-input__form" ref="form">
      <input @change="previewThumbnail" class="image-input__input" ref="fileInput" type="file" />
    </form>
    <div v-on:click="triggerInput" class="image-input__overlay"></div>
    <div class="image-input__control-buttons">
    	<button v-on:click="toBase64" type="button" class="to-base64">64</button>
      <button v-on:click="scaleUp" type="button" class="scale-up">+</button>
      <button v-on:click="scaleDown" type="button" class="scale-down">-</button>
      <button v-on:click="resetInput" type="button" class="reset-input">x</button>
    </div>

    <!-- Used in place of an image tag -->
    <canvas class="image-input__canvas"
      ref="canvas"
      v-bind:height="height"
      v-bind:width="width"
      v-bind:class="{ 'is-draggable': hoverIsDraggable }">
    </canvas>

  </div>
</script>
            
          
!
            
              /*******************************
 * HTML5 Canvas Image Uploader
 *******************************/
/* Trickery to allow hidden input, but get around safety checks by browsers */
.image-input__input 
{ 
  position: absolute;
  top: -10px; left: -10px;

  width: 9px;
  height: 9px;

  cursor: pointer;
}

.image-input__container {
  position: absolute;
  overflow: hidden;

  border: 1px dashed #FFF;
  
  box-sizing: border-box; /* display border inside */
  -moz-box-sizing: border-box;
  -webkit-box-sizing: border-box;

  &:hover {
    border: 1px solid #7FCC29;
    transition: 0.15s border;

    background: url("https://s3-us-west-2.amazonaws.com/s.cdpn.io/424395/camera.svg");
    background-size: 50px 41px;
    background-position: center;
    background-repeat: no-repeat;
  }
}

.image-input__overlay 
{
  position: absolute;
  top: 0; left: 0;

  width: 100%;
  height: 100%;

  cursor: pointer;

  .image-loaded & {
    display: none;
  }
}

.image-input__control-buttons 
{
  display: none;

  .image-loaded & { display: block; }

  position: absolute;
  top: 5px; left: 5px;

  button {
    margin: 0; padding: 0;
    width: 25px; height: 25px;
  }
}

.image-input__canvas {
  &.is-draggable {
    cursor: move;
  }
}

/*******************************
 * Demo Styles
 *******************************/

body { 
  color: #FFF;
  background-color: #533A71;
  font-family: 'Roboto', sans-serif;
}

h1 { margin-bottom: 0; }
.sub { 
  font-style: italic; 
  font-weight: 300;
}

.app-container { 
  margin: 0 auto; 
  min-width: 650px;
  max-width: 800px;
}
#app { position: relative; }

.image-uploader {
  position: absolute;
  margin: 20px 10px;
  left: 0;
}

.text-area-section {
  position: absolute;
  margin: 20px 10px;
  padding: 0;
  width: 300px;
  height: 200px;
  overflow: hidden;
  right: 0;
}

textarea {
  width: 100%;
  height: 100%;
}
            
          
!
            
              var sharedData = {
  imageData: '',
  updateImageData: function(newData){
    this.imageData = newData;
  }
};

Vue.component('image-uploader', {
  template: '#image-uploader-template',
  props: ['id','width','height'],
  // Must be a function in component definition
  data: function () {
    return {
      isImageLoaded: false,
      hoverIsDraggable: false,
      // Image
      ctx: null, canvas: null,
      img: null, 
      // Properties
      scaleSteps: 0,
      imageX: 0, imageY: 0,
      scaledImageWidth: 0, scaledImageHeight: 0,
      imageWidth: 0, imageHeight: 0, imageRight: 0, imageBottom: 0,
      // State
      draggingImage: false,
      // Mouse 
      startX: 0, startY: 0,
      mouseX: 0, mouseY: 0,
      sharedData: window.sharedData
    }
  },
  computed: {
    containerStyles: function () {
      return {
        width: this.width,
        height: this.height
      };
    }
  },
  mounted: function(){
    this.$on('get-image-base64', function(){
      console.log("ON'ING");
      this.updateTemplateImage();
    });
    
    // Instantiate
    this.canvas = this.$refs.canvas;
    this.ctx = this.canvas.getContext("2d");
    this.img = document.createElement("img");
  },
  methods: {
    toBase64: function()
    {
      var imageData = this.canvas.toDataURL("image/png");
      imageData.replace('data:image/png;base64,', '');
      this.sharedData.updateImageData(imageData);
    },
    draw: function(withBorders) 
    {
      // clear the canvas
      this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);

      // some maths
      var scaleFactor = 1 - (this.scaleSteps * .1) ;
      this.scaledImageWidth = this.img.width * scaleFactor;
      this.scaledImageHeight = this.scaledImageWidth * (this.img.height/this.img.width);

      // draw the image
      // this.ctx.drawImage(
      // this.img, (top left coords of source to use (x,y)), 
      // width & height of source to use (width, height)
      // (x,y) on canvas
      // width & height on canvas
      this.ctx.drawImage(this.img, 0, 0, this.img.width, this.img.height, this.imageX, this.imageY, this.scaledImageWidth, this.scaledImageHeight);

      this.imageRight = this.imageX + this.scaledImageWidth;
      this.imageBottom = this.imageY + this.scaledImageHeight;

      // optionally draw a box around the image (indicates "selected")
      if (withBorders) {
          this.ctx.beginPath();
          this.ctx.moveTo(this.imageX, this.imageY);
          this.ctx.lineTo(this.imageRight, this.imageY);
          this.ctx.lineTo(this.imageRight, this.imageBottom);
          this.ctx.lineTo(this.imageX, this.imageBottom);
          this.ctx.closePath();
          this.ctx.stroke();
      }
    },
    resetInput: function(){
      // clear the canvas
      this.ctx.clearRect(0, 0, this.canvas.width, this.canvas.height);
      // Reset state
      this.$refs.form.reset();
      this.isImageLoaded = false;
    },
    scaleUp: function(){
      this.scaleSteps--;
      this.draw(false);
    },
    scaleDown: function(){
      this.scaleSteps++;
      this.draw(false);
    },
    getMousePos: function(evt){
        var rect = this.canvas.getBoundingClientRect(), // abs. size of element
            scaleX = this.canvas.width / rect.width,    // relationship bitmap vs. element for X
            scaleY = this.canvas.height / rect.height;  // relationship bitmap vs. element for Y

        return {
          x: (evt.clientX - rect.left) * scaleX,   // scale mouse coordinates after they have
          y: (evt.clientY - rect.top) * scaleY     // been adjusted to be relative to element
        }
    },
    isImageHit: function(x, y){
      return (x > this.imageX && x < this.imageX + this.imageWidth && y > this.imageY && y < this.imageY + this.imageHeight);
    },
    triggerInput: function(event)
    {
      event.preventDefault();
      this.$refs.fileInput.click();
    },
    previewThumbnail: function (event) 
    {
      var vm = this;
      var input = event.target;

      if (input.files && input.files[0]) 
      {
        var reader = new FileReader();

        // Set as source
        reader.onload = function (e) {
          vm.img.src = e.target.result;
        }

        reader.readAsDataURL(input.files[0]);

        vm.img.onload = function() 
        {
          // Draw
          vm.ctx.drawImage(vm.img, 0, 0);

          // Grab position info
          vm.imageWidth = vm.img.width;
          vm.imageHeight = vm.img.height;
          vm.imageRight = vm.imageX + vm.imageWidth;
          vm.imageBottom = vm.imageY + vm.imageHeight
          
          // Update CTX
          vm.draw(false);

          // Notify component
          vm.isImageLoaded = true;
        }
      }

      function handleMouseDown(e) {
        var pos = vm.getMousePos(e);
        vm.startX = pos.x;
        vm.startY = pos.y;
        vm.draggingImage = vm.hoverIsDraggable;
      }

      function handleMouseUp(e) {
        vm.draggingImage = false;
        vm.draw(false);
      }

      function handleMouseOut(e) {
        handleMouseUp(e);
      }

      function handleMouseMove(e) 
      {
        // Update cursor property var (;
        var pos = vm.getMousePos(e);
        vm.hoverIsDraggable = vm.isImageHit(pos.x, pos.y);

        if (vm.draggingImage) 
        {
          //
          vm.mouseX = pos.x;
          vm.mouseY = pos.y;

          // move the image by the amount of the latest drag
          var dx = vm.mouseX - vm.startX;
          var dy = vm.mouseY - vm.startY;
          
          // Lock image to canvas viewport
          var collidedOnLeft = vm.imageX > 0 && dx > 0;
          var collidedOnRight = vm.imageRight < vm.canvas.width && dx < 0;
          var collidedOnTop = vm.imageY > 0 && dy > 0;
          var collidedOnBottom = vm.imageBottom < vm.canvas.height && dy < 0;

          if(collidedOnLeft) {
            vm.imageX = 0;
            vm.imageRight = vm.scaledImageWidth;
          }
          else if(collidedOnRight) {
            vm.imageX = vm.canvas.width - vm.scaledImageWidth;
            vm.imageRight = vm.canvas.width;
          } else {
            vm.imageX += dx;
            vm.imageRight += dx;
          }
          
          if(collidedOnTop) {
            vm.imageY = 0;
            vm.imageBottom = vm.scaledImageHeight;
          }
          else if(collidedOnBottom) {
            vm.imageY = vm.canvas.height - vm.scaledImageHeight;
            vm.imageBottom = vm.canvas.height;
          } else {
            vm.imageY += dy;
            vm.imageBottom += dy;
          }

          // Reset the startXY for next time
          vm.startX = vm.mouseX;
          vm.startY = vm.mouseY;

          // Redraw the image with border
          vm.draw(true);
        }
      } // END MOUSEMOVE

      // LISTEN (:
      vm.canvas.addEventListener('mousedown', handleMouseDown, false);
      vm.canvas.addEventListener('mousemove', handleMouseMove, false);
      vm.canvas.addEventListener('mouseup', handleMouseUp, false);
      vm.canvas.addEventListener('mouseout', handleMouseOut, false);
    }
  }
});

var app = new Vue({
  el: '#app',
  data: {
    sharedData: window.sharedData
  },
  methods: {}
});
            
          
!
999px
🕑 One or more of the npm packages you are using needs to be built. You're the first person to ever need it! We're building it right now and your preview will start updating again when it's ready.
Loading ..................

Console