Created
October 17, 2012 19:54
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Drawing a line between two clicked points
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| <html> | |
| <head> | |
| <script type="text/javascript"> | |
| window.onload = function() { | |
| var clicks = 0; | |
| var lastClick = [0, 0]; | |
| var canvas = document.getElementById('exemploCanvas'); | |
| canvas.addEventListener('click', draw, false); | |
| function draw(e) { | |
| ctx = this.getContext('2d'); | |
| x = getClick(e)[0]; // - this.offsetLeft; | |
| y = getClick(e)[1]; // - this.offsetTop; | |
| if (clicks != 1) { | |
| clicks++; | |
| } else { | |
| ctx.beginPath(); | |
| ctx.moveTo(lastClick[0], lastClick[1]); | |
| ctx.lineTo(x, y, 6); | |
| ctx.strokeStyle = '#000000'; | |
| ctx.stroke() | |
| clicks = 0; | |
| } | |
| lastClick = [x, y]; | |
| } | |
| function getClick(e) { | |
| var x, y; | |
| if (e.pageX != undefined && e.pageY != undefined) { | |
| x = e.pageX; | |
| y = e.pageY; | |
| } else { | |
| x = e.clientX + document.body.scrollLeft + document.documentElement.scrollLeft; | |
| y = e.clientY + document.body.scrollTop + document.documentElement.scrollTop; | |
| } | |
| return [x, y]; | |
| } | |
| } | |
| </script> | |
| </head> | |
| <body> | |
| <canvas id="exemploCanvas" width="800" height="600" style="background-color: #EEEEEE;"></canvas> | |
| </body> | |
| </html> |
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