1 /* 2 * Copyright (c) 2010 Google Inc. All rights reserved. 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions are 6 * met: 7 * 8 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above 11 * copyright notice, this list of conditions and the following disclaimer 12 * in the documentation and/or other materials provided with the 13 * distribution. 14 * * Neither the name of Google Inc. nor the names of its 15 * contributors may be used to endorse or promote products derived from 16 * this software without specific prior written permission. 17 * 18 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 */ 30 31 var LOUPE_MAGNIFICATION_FACTOR = 10; 32 33 function Loupe() 34 { 35 this._node = $('loupe'); 36 this._currentCornerX = -1; 37 this._currentCornerY = -1; 38 39 var self = this; 40 41 function handleOutputClick(event) { self._handleOutputClick(event); } 42 $('expected-image').addEventListener('click', handleOutputClick); 43 $('actual-image').addEventListener('click', handleOutputClick); 44 $('diff-canvas').addEventListener('click', handleOutputClick); 45 46 function handleLoupeClick(event) { self._handleLoupeClick(event); } 47 $('expected-loupe').addEventListener('click', handleLoupeClick); 48 $('actual-loupe').addEventListener('click', handleLoupeClick); 49 $('diff-loupe').addEventListener('click', handleLoupeClick); 50 51 function hide(event) { self.hide(); } 52 $('loupe-close').addEventListener('click', hide); 53 } 54 55 Loupe.prototype._handleOutputClick = function(event) 56 { 57 // The -1 compensates for the border around the image/canvas. 58 this._showFor(event.offsetX - 1, event.offsetY - 1); 59 }; 60 61 Loupe.prototype._handleLoupeClick = function(event) 62 { 63 var deltaX = Math.floor(event.offsetX/LOUPE_MAGNIFICATION_FACTOR); 64 var deltaY = Math.floor(event.offsetY/LOUPE_MAGNIFICATION_FACTOR); 65 66 this._showFor( 67 this._currentCornerX + deltaX, this._currentCornerY + deltaY); 68 } 69 70 Loupe.prototype.hide = function() 71 { 72 this._node.style.display = 'none'; 73 }; 74 75 Loupe.prototype._showFor = function(x, y) 76 { 77 this._fillFromImage(x, y, 'expected', $('expected-image')); 78 this._fillFromImage(x, y, 'actual', $('actual-image')); 79 this._fillFromCanvas(x, y, 'diff', $('diff-canvas')); 80 81 this._node.style.display = ''; 82 }; 83 84 Loupe.prototype._fillFromImage = function(x, y, type, sourceImage) 85 { 86 var tempCanvas = document.createElement('canvas'); 87 tempCanvas.width = sourceImage.width; 88 tempCanvas.height = sourceImage.height; 89 var tempContext = tempCanvas.getContext('2d'); 90 91 tempContext.drawImage(sourceImage, 0, 0); 92 93 this._fillFromCanvas(x, y, type, tempCanvas); 94 }; 95 96 Loupe.prototype._fillFromCanvas = function(x, y, type, canvas) 97 { 98 var context = canvas.getContext('2d'); 99 var sourceImageData = 100 context.getImageData(0, 0, canvas.width, canvas.height); 101 102 var targetCanvas = $(type + '-loupe'); 103 var targetContext = targetCanvas.getContext('2d'); 104 targetContext.fillStyle = 'rgba(255, 255, 255, 1)'; 105 targetContext.fillRect(0, 0, targetCanvas.width, targetCanvas.height); 106 107 var sourceXOffset = (targetCanvas.width/LOUPE_MAGNIFICATION_FACTOR - 1)/2; 108 var sourceYOffset = (targetCanvas.height/LOUPE_MAGNIFICATION_FACTOR - 1)/2; 109 110 function readPixelComponent(x, y, component) { 111 var offset = (y * sourceImageData.width + x) * 4 + component; 112 return sourceImageData.data[offset]; 113 } 114 115 for (var i = -sourceXOffset; i <= sourceXOffset; i++) { 116 for (var j = -sourceYOffset; j <= sourceYOffset; j++) { 117 var sourceX = x + i; 118 var sourceY = y + j; 119 120 var sourceR = readPixelComponent(sourceX, sourceY, 0); 121 var sourceG = readPixelComponent(sourceX, sourceY, 1); 122 var sourceB = readPixelComponent(sourceX, sourceY, 2); 123 var sourceA = readPixelComponent(sourceX, sourceY, 3)/255; 124 sourceA = Math.round(sourceA * 10)/10; 125 126 var targetX = (i + sourceXOffset) * LOUPE_MAGNIFICATION_FACTOR; 127 var targetY = (j + sourceYOffset) * LOUPE_MAGNIFICATION_FACTOR; 128 var colorString = 129 sourceR + ', ' + sourceG + ', ' + sourceB + ', ' + sourceA; 130 targetContext.fillStyle = 'rgba(' + colorString + ')'; 131 targetContext.fillRect( 132 targetX, targetY, 133 LOUPE_MAGNIFICATION_FACTOR, LOUPE_MAGNIFICATION_FACTOR); 134 135 if (i == 0 && j == 0) { 136 $('loupe-coordinate').textContent = sourceX + ', ' + sourceY; 137 $(type + '-loupe-color').textContent = colorString; 138 } 139 } 140 } 141 142 this._currentCornerX = x - sourceXOffset; 143 this._currentCornerY = y - sourceYOffset; 144 }; 145