HTML5 Canvas Drag, Drop, and Resize Images

Code Editor

<!DOCTYPE HTML>
<html>
  <head>
    <style>
      body {
        margin: 0px;
        padding: 0px;
      }
    </style>
  </head>
  <body onmousedown="return false;">
    <div id="container"></div>
    <script src="http://d3lp1msu2r81bx.cloudfront.net/kjs/js/lib/kinetic-v4.4.0.min.js"></script>
    <script>
      function update(activeAnchor) {
        var group = activeAnchor.getParent();

var topLeft = group.get('.topLeft')[0];
        var topRight = group.get('.topRight')[0];
        var bottomRight = group.get('.bottomRight')[0];
        var bottomLeft = group.get('.bottomLeft')[0];
        var image = group.get('.image')[0];

var anchorX = activeAnchor.getX();
        var anchorY = activeAnchor.getY();

// update anchor positions
        switch (activeAnchor.getName()) {
          case 'topLeft':
            topRight.setY(anchorY);
            bottomLeft.setX(anchorX);
            break;
          case 'topRight':
            topLeft.setY(anchorY);
            bottomRight.setX(anchorX);
            break;
          case 'bottomRight':
            bottomLeft.setY(anchorY);
            topRight.setX(anchorX); 
            break;
          case 'bottomLeft':
            bottomRight.setY(anchorY);
            topLeft.setX(anchorX); 
            break;
        }

image.setPosition(topLeft.getPosition());

var width = topRight.getX() - topLeft.getX();
        var height = bottomLeft.getY() - topLeft.getY();
        if(width && height) {
          image.setSize(width, height);
        }
      }
      function addAnchor(group, x, y, name) {
        var stage = group.getStage();
        var layer = group.getLayer();

var anchor = new Kinetic.Circle({
          x: x,
          y: y,
          stroke: '#666',
          fill: '#ddd',
          strokeWidth: 2,
          radius: 8,
          name: name,
          draggable: true,
          dragOnTop: false
        });

anchor.on('dragmove', function() {
          update(this);
          layer.draw();
        });
        anchor.on('mousedown touchstart', function() {
          group.setDraggable(false);
          this.moveToTop();
        });
        anchor.on('dragend', function() {
          group.setDraggable(true);
          layer.draw();
        });
        // add hover styling
        anchor.on('mouseover', function() {
          var layer = this.getLayer();
          document.body.style.cursor = 'pointer';
          this.setStrokeWidth(4);
          layer.draw();
        });
        anchor.on('mouseout', function() {
          var layer = this.getLayer();
          document.body.style.cursor = 'default';
          this.setStrokeWidth(2);
          layer.draw();
        });

group.add(anchor);
      }
      function loadImages(sources, callback) {
        var images = {};
        var loadedImages = 0;
        var numImages = 0;
        for(var src in sources) {
          numImages++;
        }
        for(var src in sources) {
          images[src] = new Image();
          images[src].onload = function() {
            if(++loadedImages >= numImages) {
              callback(images);
            }
          };
          images[src].src = sources[src];
        }
      }
      function initStage(images) {
        var stage = new Kinetic.Stage({
          container: 'container',
          width: 578,
          height: 400
        });
        var darthVaderGroup = new Kinetic.Group({
          x: 270,
          y: 100,
          draggable: true
        });
        var yodaGroup = new Kinetic.Group({
          x: 100,
          y: 110,
          draggable: true
        });
        var layer = new Kinetic.Layer();

/*
         * go ahead and add the groups
         * to the layer and the layer to the
         * stage so that the groups have knowledge
         * of its layer and stage
         */
        layer.add(darthVaderGroup);
        layer.add(yodaGroup);
        stage.add(layer);

// darth vader
        var darthVaderImg = new Kinetic.Image({
          x: 0,
          y: 0,
          image: images.darthVader,
          width: 200,
          height: 138,
          name: 'image'
        });

darthVaderGroup.add(darthVaderImg);
        addAnchor(darthVaderGroup, 0, 0, 'topLeft');
        addAnchor(darthVaderGroup, 200, 0, 'topRight');
        addAnchor(darthVaderGroup, 200, 138, 'bottomRight');
        addAnchor(darthVaderGroup, 0, 138, 'bottomLeft');

darthVaderGroup.on('dragstart', function() {
          this.moveToTop();
        });
        // yoda
        var yodaImg = new Kinetic.Image({
          x: 0,
          y: 0,
          image: images.yoda,
          width: 93,
          height: 104,
          name: 'image'
        });

yodaGroup.add(yodaImg);
        addAnchor(yodaGroup, 0, 0, 'topLeft');
        addAnchor(yodaGroup, 93, 0, 'topRight');
        addAnchor(yodaGroup, 93, 104, 'bottomRight');
        addAnchor(yodaGroup, 0, 104, 'bottomLeft');

yodaGroup.on('dragstart', function() {
          this.moveToTop();
        });

stage.draw();
      }

var sources = {
        darthVader: 'http://www.html5canvastutorials.com/demos/assets/darth-vader.jpg',
        yoda: 'http://www.html5canvastutorials.com/demos/assets/yoda.jpg'
      };
      loadImages(sources, initStage);

</script>
  
  </body>
</html>

< Oscillating Bubble Shape Tooltips >

More Examples

Modified on January 24th, 2013 by Eric Rowell