"use strict";
+/**
+ * @constructor
+ *
+ * This gets called when there are "new points" to chart. This is generally the
+ * case when the underlying data being charted has changed. It is _not_ called
+ * in the common case that the user has zoomed or is panning the view.
+ *
+ * The chart canvas has already been created by the Dygraph object. The
+ * renderer simply gets a drawing context.
+ *
+ * @param {Dyraph} dygraph The chart to which this renderer belongs.
+ * @param {Canvas} element The <canvas> DOM element on which to draw.
+ * @param {CanvasRenderingContext2D} elementContext The drawing context.
+ * @param {DygraphLayout} layout The chart's DygraphLayout object.
+ *
+ * TODO(danvk): remove the elementContext property.
+ */
var DygraphCanvasRenderer = function(dygraph, element, elementContext, layout) {
this.dygraph_ = dygraph;
this.xlabels = [];
this.ylabels = [];
this.annotations = [];
- this.chartLabels = {};
this.area = layout.getPlotArea();
this.container.style.position = "relative";
return this.dygraph_.attr_(x);
};
+/**
+ * Clears out all chart content and DOM elements.
+ * This is called immediately before render() on every frame, including
+ * during zooms and pans.
+ * @private
+ */
DygraphCanvasRenderer.prototype.clear = function() {
var context;
if (this.isIE) {
removeArray(this.ylabels);
removeArray(this.annotations);
- for (var k in this.chartLabels) {
- if (!this.chartLabels.hasOwnProperty(k)) continue;
- var el = this.chartLabels[k];
- if (el.parentNode) el.parentNode.removeChild(el);
- }
this.xlabels = [];
this.ylabels = [];
this.annotations = [];
- this.chartLabels = {};
};
-
+/**
+ * Checks whether the browser supports the <canvas> tag.
+ * @private
+ */
DygraphCanvasRenderer.isSupported = function(canvasName) {
var canvas = null;
try {
};
/**
- * Draw an X/Y grid on top of the existing plot
+ * This method is responsible for drawing everything on the chart, including
+ * lines, error bars, fills and axes.
+ * It is called immediately after clear() on every frame, including during pans
+ * and zooms.
+ * @private
*/
DygraphCanvasRenderer.prototype.render = function() {
// Draw the new X/Y grid. Lines appear crisper when pixels are rounded to
// Do the ordinary rendering, as before
this._renderLineChart();
this._renderAxis();
- this._renderChartLabels();
- this._renderAnnotations();
+ // this._renderAnnotations();
};
DygraphCanvasRenderer.prototype._createIEClipArea = function() {
};
-DygraphCanvasRenderer.prototype._renderChartLabels = function() {
- var div, class_div;
-
- // Generate divs for the chart title, xlabel and ylabel.
- // Space for these divs has already been taken away from the charting area in
- // the DygraphCanvasRenderer constructor.
- if (this.attr_('title')) {
- div = document.createElement("div");
- div.style.position = 'absolute';
- div.style.top = '0px';
- div.style.left = this.area.x + 'px';
- div.style.width = this.area.w + 'px';
- div.style.height = this.attr_('titleHeight') + 'px';
- div.style.textAlign = 'center';
- div.style.fontSize = (this.attr_('titleHeight') - 8) + 'px';
- div.style.fontWeight = 'bold';
- class_div = document.createElement("div");
- class_div.className = 'dygraph-label dygraph-title';
- class_div.innerHTML = this.attr_('title');
- div.appendChild(class_div);
- this.container.appendChild(div);
- this.chartLabels.title = div;
- }
-
- if (this.attr_('xlabel')) {
- div = document.createElement("div");
- div.style.position = 'absolute';
- div.style.bottom = 0; // TODO(danvk): this is lazy. Calculate style.top.
- div.style.left = this.area.x + 'px';
- div.style.width = this.area.w + 'px';
- div.style.height = this.attr_('xLabelHeight') + 'px';
- div.style.textAlign = 'center';
- div.style.fontSize = (this.attr_('xLabelHeight') - 2) + 'px';
-
- class_div = document.createElement("div");
- class_div.className = 'dygraph-label dygraph-xlabel';
- class_div.innerHTML = this.attr_('xlabel');
- div.appendChild(class_div);
- this.container.appendChild(div);
- this.chartLabels.xlabel = div;
- }
-
- var that = this;
- function createRotatedDiv(axis, classes, html) {
- var box = {
- left: 0,
- top: that.area.y,
- width: that.attr_('yLabelWidth'),
- height: that.area.h
- };
- // TODO(danvk): is this outer div actually necessary?
- div = document.createElement("div");
- div.style.position = 'absolute';
- if (axis == 1) {
- div.style.left = box.left;
- } else {
- div.style.right = box.left;
- }
- div.style.top = box.top + 'px';
- div.style.width = box.width + 'px';
- div.style.height = box.height + 'px';
- div.style.fontSize = (that.attr_('yLabelWidth') - 2) + 'px';
-
- var inner_div = document.createElement("div");
- inner_div.style.position = 'absolute';
- inner_div.style.width = box.height + 'px';
- inner_div.style.height = box.width + 'px';
- inner_div.style.top = (box.height / 2 - box.width / 2) + 'px';
- inner_div.style.left = (box.width / 2 - box.height / 2) + 'px';
- inner_div.style.textAlign = 'center';
-
- // CSS rotation is an HTML5 feature which is not standardized. Hence every
- // browser has its own name for the CSS style.
- var val = 'rotate(' + (axis == 1 ? '-' : '') + '90deg)';
- inner_div.style.transform = val; // HTML5
- inner_div.style.WebkitTransform = val; // Safari/Chrome
- inner_div.style.MozTransform = val; // Firefox
- inner_div.style.OTransform = val; // Opera
- inner_div.style.msTransform = val; // IE9
-
- if (typeof(document.documentMode) !== 'undefined' &&
- document.documentMode < 9) {
- // We're dealing w/ an old version of IE, so we have to rotate the text
- // using a BasicImage transform. This uses a different origin of rotation
- // than HTML5 rotation (top left of div vs. its center).
- inner_div.style.filter =
- 'progid:DXImageTransform.Microsoft.BasicImage(rotation=' +
- (axis == 1 ? '3' : '1') + ')';
- inner_div.style.left = '0px';
- inner_div.style.top = '0px';
- }
-
- class_div = document.createElement("div");
- class_div.className = classes;
- class_div.innerHTML = html;
-
- inner_div.appendChild(class_div);
- div.appendChild(inner_div);
- return div;
- }
-
- var div;
- if (this.attr_('ylabel')) {
- div = createRotatedDiv(1, 'dygraph-label dygraph-ylabel',
- this.attr_('ylabel'));
- this.container.appendChild(div);
- this.chartLabels.ylabel = div;
- }
- if (this.attr_('y2label') && this.dygraph_.numAxes() == 2) {
- div = createRotatedDiv(2, 'dygraph-label dygraph-y2label',
- this.attr_('y2label'));
- this.container.appendChild(div);
- this.chartLabels.y2label = div;
- }
-};
-
-
DygraphCanvasRenderer.prototype._renderAnnotations = function() {
var annotationStyle = {
"position": "absolute",
DygraphCanvasRenderer._predicateThatSkipsEmptyPoints =
function(array, idx) { return array[idx].yval !== null; }
-DygraphCanvasRenderer.isNullOrNaN_ = function(x) {
- return (x === null || isNaN(x));
-};
-
DygraphCanvasRenderer.prototype._drawStyledLine = function(
ctx, i, setName, color, strokeWidth, strokePattern, drawPoints,
drawPointCallback, pointSize) {
var iter = Dygraph.createIterator(points, firstIndexInSet, setLength,
DygraphCanvasRenderer._getIteratorPredicate(this.attr_("connectSeparatedPoints")));
- if (strokeWidth && !stepPlot && (!strokePattern || strokePattern.length <= 1)) {
- this._drawTrivialLine(ctx, iter, setName, color, strokeWidth, drawPointCallback, pointSize, drawPoints, drawGapPoints);
+ var pointsOnLine;
+ var strategy;
+ if (!strokePattern || strokePattern.length <= 1) {
+ strategy = trivialStrategy(ctx, color, strokeWidth);
} else {
- this._drawNonTrivialLine(ctx, iter, setName, color, strokeWidth, strokePattern, drawPointCallback, pointSize, drawPoints, drawGapPoints, stepPlot);
+ strategy = nonTrivialStrategy(this, ctx, color, strokeWidth, strokePattern);
}
+ pointsOnLine = this._drawSeries(ctx, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, strategy);
+ this._drawPointsOnLine(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize);
+
ctx.restore();
};
+var nonTrivialStrategy = function(renderer, ctx, color, strokeWidth, strokePattern) {
+ return new function() {
+ this.init = function() { };
+ this.finish = function() { };
+ this.startSegment = function() {
+ ctx.beginPath();
+ ctx.strokeStyle = color;
+ ctx.lineWidth = strokeWidth;
+ };
+ this.endSegment = function() {
+ ctx.stroke(); // should this include closePath?
+ };
+ this.drawLine = function(x1, y1, x2, y2) {
+ renderer._dashedLine(ctx, x1, y1, x2, y2, strokePattern);
+ };
+ this.skipPixel = function(prevX, prevY, curX, curY) {
+ // TODO(konigsberg): optimize with http://jsperf.com/math-round-vs-hack/6 ?
+ return (Math.round(prevX) == Math.round(curX) &&
+ Math.round(prevY) == Math.round(curY));
+ };
+ };
+};
+
+var trivialStrategy = function(ctx, color, strokeWidth) {
+ return new function() {
+ this.init = function() {
+ ctx.beginPath();
+ ctx.strokeStyle = color;
+ ctx.lineWidth = strokeWidth;
+ };
+ this.finish = function() {
+ ctx.stroke(); // should this include closePath?
+ };
+ this.startSegment = function() { };
+ this.endSegment = function() { };
+ this.drawLine = function(x1, y1, x2, y2) {
+ ctx.moveTo(x1, y1);
+ ctx.lineTo(x2, y2);
+ };
+ // don't skip pixels.
+ this.skipPixel = function() {
+ return false;
+ };
+ };
+};
+
DygraphCanvasRenderer.prototype._drawPointsOnLine = function(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize) {
for (var idx = 0; idx < pointsOnLine.length; idx++) {
var cb = pointsOnLine[idx];
}
}
-DygraphCanvasRenderer.prototype._drawNonTrivialLine = function(
- ctx, iter, setName, color, strokeWidth, strokePattern, drawPointCallback, pointSize, drawPoints, drawGapPoints, stepPlot) {
- var prevX = null;
- var prevY = null;
- var nextY = null;
- var point;
+DygraphCanvasRenderer.prototype._drawSeries = function(
+ ctx, iter, strokeWidth, pointSize, drawPoints, drawGapPoints,
+ stepPlot, strategy) {
+
+ var prevCanvasX = null;
+ var prevCanvasY = null;
+ var nextCanvasY = null;
+ var isIsolated; // true if this point is isolated (no line segments)
+ var point; // the point being processed in the while loop
var pointsOnLine = []; // Array of [canvasx, canvasy] pairs.
- var first = true;
+ var first = true; // the first cycle through the while loop
+
+ strategy.init();
+
while(iter.hasNext()) {
point = iter.next();
- nextY = iter.hasNext() ? iter.peek().canvasy : null;
- if (DygraphCanvasRenderer.isNullOrNaN_(point.canvasy)) {
- if (stepPlot && prevX !== null) {
+ if (point.canvasy === null || point.canvasy != point.canvasy) {
+ if (stepPlot && prevCanvasX !== null) {
// Draw a horizontal line to the start of the missing data
- ctx.beginPath();
- ctx.strokeStyle = color;
- ctx.lineWidth = this.attr_('strokeWidth');
- this._dashedLine(ctx, prevX, prevY, point.canvasx, prevY, strokePattern);
- ctx.stroke();
+ strategy.startSegment();
+ strategy.drawLine(prevX, prevY, point.canvasx, prevY);
+ strategy.endSegment();
}
- // this will make us move to the next point, not draw a line to it.
- prevX = prevY = null;
+ prevCanvasX = prevCanvasY = null;
} else {
- // A point is "isolated" if it is non-null but both the previous
- // and next points are null.
- var isIsolated = (!prevX && DygraphCanvasRenderer.isNullOrNaN_(nextY));
+ nextCanvasY = iter.hasNext() ? iter.peek().canvasy : null;
+ // TODO: we calculate isNullOrNaN for this point, and the next, and then, when
+ // we iterate, test for isNullOrNaN again. Why bother?
+ var isNextCanvasYNullOrNaN = nextCanvasY === null || nextCanvasY != nextCanvasY;
+ isIsolated = (!prevCanvasX && isNextCanvasYNullOrNaN);
if (drawGapPoints) {
- // Also consider a point to be is "isolated" if it's adjacent to a
+ // Also consider a point to be "isolated" if it's adjacent to a
// null point, excluding the graph edges.
- if ((!first && !prevX) ||
- (iter.hasNext() && DygraphCanvasRenderer.isNullOrNaN_(nextY))) {
+ if ((!first && !prevCanvasX) ||
+ (iter.hasNext() && isNextCanvasYNullOrNaN)) {
isIsolated = true;
}
}
- if (prevX === null) {
- prevX = point.canvasx;
- prevY = point.canvasy;
- } else {
- // Skip over points that will be drawn in the same pixel.
- if (Math.round(prevX) == Math.round(point.canvasx) &&
- Math.round(prevY) == Math.round(point.canvasy)) {
+ if (prevCanvasX !== null) {
+ if (strategy.skipPixel(prevCanvasX, prevCanvasY, point.canvasx, point.canvasy)) {
continue;
}
- // TODO(antrob): skip over points that lie on a line that is already
- // going to be drawn. There is no need to have more than 2
- // consecutive points that are collinear.
if (strokeWidth) {
- ctx.beginPath();
- ctx.strokeStyle = color;
- ctx.lineWidth = strokeWidth;
+ strategy.startSegment();
if (stepPlot) {
- this._dashedLine(ctx, prevX, prevY, point.canvasx, prevY, strokePattern);
- prevX = point.canvasx;
+ strategy.drawLine(prevCanvasX, prevCanvasY, point.canvasx, prevCanvasY);
+ prevCanvasX = point.canvasx;
}
- this._dashedLine(ctx, prevX, prevY, point.canvasx, point.canvasy, strokePattern);
- prevX = point.canvasx;
- prevY = point.canvasy;
- ctx.stroke();
+ strategy.drawLine(prevCanvasX, prevCanvasY, point.canvasx, point.canvasy);
+ strategy.endSegment();
}
}
-
if (drawPoints || isIsolated) {
pointsOnLine.push([point.canvasx, point.canvasy]);
}
+ prevCanvasX = point.canvasx;
+ prevCanvasY = point.canvasy;
}
first = false;
}
- this._drawPointsOnLine(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize);
-};
-
-DygraphCanvasRenderer.prototype._drawTrivialLine = function(
- ctx, iter, setName, color, strokeWidth, drawPointCallback, pointSize, drawPoints, drawGapPoints) {
- var prevX = null;
- var prevY = null;
- var nextY = null;
- var pointsOnLine = []; // Array of [canvasx, canvasy] pairs.
- ctx.beginPath();
- ctx.strokeStyle = color;
- ctx.lineWidth = strokeWidth;
- var first = true;
- while(iter.hasNext()) {
- var point = iter.next();
- nextY = iter.hasNext() ? iter.peek().canvasy : null;
- if (DygraphCanvasRenderer.isNullOrNaN_(point.canvasy)) {
- prevX = prevY = null;
- } else {
- var isIsolated = (!prevX && DygraphCanvasRenderer.isNullOrNaN_(nextY));
- if (drawGapPoints) {
- // Also consider a point to be is "isolated" if it's adjacent to a
- // null point, excluding the graph edges.
- if ((!first && !prevX) ||
- (iter.hasNext() && DygraphCanvasRenderer.isNullOrNaN_(nextY))) {
- isIsolated = true;
- }
- }
- if (prevX === null) {
- prevX = point.canvasx;
- prevY = point.canvasy;
- ctx.moveTo(point.canvasx, point.canvasy);
- } else {
- ctx.lineTo(point.canvasx, point.canvasy);
- }
- if (drawPoints || isIsolated) {
- pointsOnLine.push([point.canvasx, point.canvasy]);
- }
- }
- first = false;
- }
- ctx.stroke();
- this._drawPointsOnLine(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize);
+ strategy.finish();
+ return pointsOnLine;
};
DygraphCanvasRenderer.prototype._drawLine = function(ctx, i) {
var drawPointCallback = this.dygraph_.attr_("drawPointCallback", setName) ||
Dygraph.Circles.DEFAULT;
- // TODO(konigsberg): Turn this into one call, and then consider inlining drawStyledLine.
if (borderWidth && strokeWidth) {
this._drawStyledLine(ctx, i, setName,
this.dygraph_.attr_("strokeBorderColor", setName),
var setCount = setNames.length;
// TODO(danvk): Move this mapping into Dygraph and get it out of here.
- this.colors = {};
- for (i = 0; i < setCount; i++) {
- this.colors[setNames[i]] = this.colorScheme_[i % this.colorScheme_.length];
- }
+ this.colors = this.dygraph_.colorsMap_;
+ // for (i = 0; i < setCount; i++) {
+ // this.colors[setNames[i]] = this.colorScheme_[i % this.colorScheme_.length];
+ // }
// Update Points
// TODO(danvk): here
projects / dygraphs.git / blobdiff