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author | 2017-09-01 11:57:47 +0800 | |
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committer | 2017-09-01 11:57:58 +0800 | |
commit | 57dbba269d19bc59fad89160200bb2dbcccb9003 (patch) | |
tree | d466041ceffa2161124ca79a48b3e077777c74b8 /usecaseui-common/src/main/webapp/static/fusion/raptor/dy3/js/dashed-canvas.js | |
parent | 4ff32341a0af1972b44a7410e76e9b231131e7ab (diff) |
Upload Monitor function code
Change-Id: I33ad76221b4cb771a298ff240245fc24be664efb
Issue-Id: USECASEUI-6
Signed-off-by: shentao <shentao@chinamobile.com>
Diffstat (limited to 'usecaseui-common/src/main/webapp/static/fusion/raptor/dy3/js/dashed-canvas.js')
-rw-r--r-- | usecaseui-common/src/main/webapp/static/fusion/raptor/dy3/js/dashed-canvas.js | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/usecaseui-common/src/main/webapp/static/fusion/raptor/dy3/js/dashed-canvas.js b/usecaseui-common/src/main/webapp/static/fusion/raptor/dy3/js/dashed-canvas.js new file mode 100644 index 00000000..cec77298 --- /dev/null +++ b/usecaseui-common/src/main/webapp/static/fusion/raptor/dy3/js/dashed-canvas.js @@ -0,0 +1,176 @@ +/** + * @license + * Copyright 2012 Dan Vanderkam (danvdk@gmail.com) + * MIT-licensed (http://opensource.org/licenses/MIT) + */ + +/** + * @fileoverview Adds support for dashed lines to the HTML5 canvas. + * + * Usage: + * var ctx = canvas.getContext("2d"); + * ctx.installPattern([10, 5]) // draw 10 pixels, skip 5 pixels, repeat. + * ctx.beginPath(); + * ctx.moveTo(100, 100); // start the first line segment. + * ctx.lineTo(150, 200); + * ctx.lineTo(200, 100); + * ctx.moveTo(300, 150); // start a second, unconnected line + * ctx.lineTo(400, 250); + * ... + * ctx.stroke(); // draw the dashed line. + * ctx.uninstallPattern(); + * + * This is designed to leave the canvas untouched when it's not used. + * If you never install a pattern, or call uninstallPattern(), then the canvas + * will be exactly as it would have if you'd never used this library. The only + * difference from the standard canvas will be the "installPattern" method of + * the drawing context. + */ + +/** + * Change the stroking style of the canvas drawing context from a solid line to + * a pattern (e.g. dashes, dash-dot-dash, etc.) + * + * Once you've installed the pattern, you can draw with it by using the + * beginPath(), moveTo(), lineTo() and stroke() method calls. Note that some + * more advanced methods (e.g. quadraticCurveTo() and bezierCurveTo()) are not + * supported. See file overview for a working example. + * + * Side effects of calling this method include adding an "isPatternInstalled" + * property and "uninstallPattern" method to this particular canvas context. + * You must call uninstallPattern() before calling installPattern() again. + * + * @param {Array.<number>} pattern A description of the stroke pattern. Even + * indices indicate a draw and odd indices indicate a gap (in pixels). The + * array should have a even length as any odd lengthed array could be expressed + * as a smaller even length array. + */ +CanvasRenderingContext2D.prototype.installPattern = function(pattern) { + "use strict"; + + if (typeof(this.isPatternInstalled) !== 'undefined') { + throw "Must un-install old line pattern before installing a new one."; + } + this.isPatternInstalled = true; + + var dashedLineToHistory = [0, 0]; + + // list of connected line segements: + // [ [x1, y1], ..., [xn, yn] ], [ [x1, y1], ..., [xn, yn] ] + var segments = []; + + // Stash away copies of the unmodified line-drawing functions. + var realBeginPath = this.beginPath; + var realLineTo = this.lineTo; + var realMoveTo = this.moveTo; + var realStroke = this.stroke; + + /** @type {function()|undefined} */ + this.uninstallPattern = function() { + this.beginPath = realBeginPath; + this.lineTo = realLineTo; + this.moveTo = realMoveTo; + this.stroke = realStroke; + this.uninstallPattern = undefined; + this.isPatternInstalled = undefined; + }; + + // Keep our own copies of the line segments as they're drawn. + this.beginPath = function() { + segments = []; + realBeginPath.call(this); + }; + this.moveTo = function(x, y) { + segments.push([[x, y]]); + realMoveTo.call(this, x, y); + }; + this.lineTo = function(x, y) { + var last = segments[segments.length - 1]; + last.push([x, y]); + }; + + this.stroke = function() { + if (segments.length === 0) { + // Maybe the user is drawing something other than a line. + // TODO(danvk): test this case. + realStroke.call(this); + return; + } + + for (var i = 0; i < segments.length; i++) { + var seg = segments[i]; + var x1 = seg[0][0], y1 = seg[0][1]; + for (var j = 1; j < seg.length; j++) { + // Draw a dashed line from (x1, y1) - (x2, y2) + var x2 = seg[j][0], y2 = seg[j][1]; + this.save(); + + // Calculate transformation parameters + var dx = (x2-x1); + var dy = (y2-y1); + var len = Math.sqrt(dx*dx + dy*dy); + var rot = Math.atan2(dy, dx); + + // Set transformation + this.translate(x1, y1); + realMoveTo.call(this, 0, 0); + this.rotate(rot); + + // Set last pattern index we used for this pattern. + var patternIndex = dashedLineToHistory[0]; + var x = 0; + while (len > x) { + // Get the length of the pattern segment we are dealing with. + var segment = pattern[patternIndex]; + // If our last draw didn't complete the pattern segment all the way + // we will try to finish it. Otherwise we will try to do the whole + // segment. + if (dashedLineToHistory[1]) { + x += dashedLineToHistory[1]; + } else { + x += segment; + } + + if (x > len) { + // We were unable to complete this pattern index all the way, keep + // where we are the history so our next draw continues where we + // left off in the pattern. + dashedLineToHistory = [patternIndex, x-len]; + x = len; + } else { + // We completed this patternIndex, we put in the history that we + // are on the beginning of the next segment. + dashedLineToHistory = [(patternIndex+1)%pattern.length, 0]; + } + + // We do a line on a even pattern index and just move on a odd + // pattern index. The move is the empty space in the dash. + if (patternIndex % 2 === 0) { + realLineTo.call(this, x, 0); + } else { + realMoveTo.call(this, x, 0); + } + + // If we are not done, next loop process the next pattern segment, or + // the first segment again if we are at the end of the pattern. + patternIndex = (patternIndex+1) % pattern.length; + } + + this.restore(); + x1 = x2, y1 = y2; + } + } + realStroke.call(this); + segments = []; + }; +}; + +/** + * Removes the previously-installed pattern. + * You must call installPattern() before calling this. You can install at most + * one pattern at a time--there is no pattern stack. + */ +CanvasRenderingContext2D.prototype.uninstallPattern = function() { + // This will be replaced by a non-error version when a pattern is installed. + throw "Must install a line pattern before uninstalling it."; +} |