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ink pad widget
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| <!doctype html> | |
| <html> | |
| <head> | |
| <script src="inkpad.js"></script> | |
| <style> | |
| body { | |
| margin: 0; padding: 0; | |
| } | |
| ink-pad#ink { | |
| position: absolute; | |
| left: 0; right: 50%; top: 0; bottom: 0; | |
| background: fuchsia; | |
| } | |
| ink-pad#moreink { | |
| position: absolute; | |
| left: 50%; right: 0; top: 0; bottom: 0; | |
| background: #7ef; | |
| } | |
| </style> | |
| </head> | |
| <body> | |
| <ink-pad id="ink"></ink-pad> | |
| <ink-pad id="moreink"></ink-pad> | |
| <script> | |
| // You can play with the canvases in the console. I thought this was | |
| // pretty: | |
| ink.ctx.lineWidth = 10; | |
| ink.ctx.strokeStyle = 'rgba(119, 238, 255, 0.05)'; | |
| moreink.ctx.lineWidth = 10; | |
| moreink.ctx.strokeStyle = 'rgba(255, 0, 255, 0.05)'; | |
| </script> | |
| </body> | |
| </html> |
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| // inkPad < HTMLElement | |
| var inkPad = Object.create(HTMLElement.prototype); | |
| inkPad.createdCallback = function() { | |
| this.canvas = document.createElement('canvas'); | |
| this.canvas.height = this.clientHeight; | |
| this.canvas.width = this.clientWidth; | |
| this.appendChild(this.canvas); | |
| this.ctx = this.canvas.getContext('2d'); | |
| var drawing = false; | |
| this.addEventListener('mousedown', function(event) { | |
| drawing = true; | |
| this.ctx.beginPath(); | |
| // event.offsetX! offsetX, not just x! x isn't even | |
| // well defined, apparently. | |
| // | |
| // The browser wants you dead, man. | |
| // http://www.quirksmode.org/dom/w3c_cssom.html#mousepos | |
| this.ctx.moveTo(event.offsetX, event.offsetY); | |
| }); | |
| this.addEventListener('mousemove', function(event) { | |
| if (drawing) { | |
| this.ctx.lineTo(event.offsetX, event.offsetY); | |
| this.ctx.stroke(); | |
| } | |
| }); | |
| this.addEventListener('mouseup', function(event) { | |
| drawing = false; | |
| }); | |
| } | |
| document.registerElement('ink-pad', {prototype: inkPad}); |
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