+DygraphCanvasRenderer._drawStyledLine = function(e,
+ color, strokeWidth, strokePattern, drawPoints,
+ drawPointCallback, pointSize) {
+ var g = e.dygraph;
+ // TODO(konigsberg): Compute attributes outside this method call.
+ var stepPlot = g.getOption("stepPlot"); // TODO(danvk): per-series
+ if (!Dygraph.isArrayLike(strokePattern)) {
+ strokePattern = null;
+ }
+
+ var drawGapPoints = g.getOption('drawGapEdgePoints', e.setName);
+
+ var points = e.points;
+ var iter = Dygraph.createIterator(points, 0, points.length,
+ DygraphCanvasRenderer._getIteratorPredicate(
+ g.getOption("connectSeparatedPoints"))); // TODO(danvk): per-series?
+
+ var stroking = strokePattern && (strokePattern.length >= 2);
+
+ var ctx = e.drawingContext;
+ ctx.save();
+ if (stroking) {
+ ctx.installPattern(strokePattern);
+ }
+
+ var pointsOnLine = DygraphCanvasRenderer._drawSeries(
+ e, iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, color);
+ DygraphCanvasRenderer._drawPointsOnLine(
+ e, pointsOnLine, drawPointCallback, color, pointSize);
+
+ if (stroking) {
+ ctx.uninstallPattern();
+ }
+
+ ctx.restore();
+};
+
+/**
+ * This does the actual drawing of lines on the canvas, for just one series.
+ * Returns a list of [canvasx, canvasy] pairs for points for which a
+ * drawPointCallback should be fired. These include isolated points, or all
+ * points if drawPoints=true.
+ * @param {Object} e The dictionary passed to the plotter function.
+ * @private
+ */
+DygraphCanvasRenderer._drawSeries = function(e,
+ iter, strokeWidth, pointSize, drawPoints, drawGapPoints, stepPlot, color) {
+
+ 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; // the first cycle through the while loop
+
+ var ctx = e.drawingContext;
+ ctx.beginPath();
+ ctx.strokeStyle = color;
+ ctx.lineWidth = strokeWidth;
+
+ // NOTE: we break the iterator's encapsulation here for about a 25% speedup.
+ var arr = iter.array_;
+ var limit = iter.end_;
+ var predicate = iter.predicate_;
+
+ for (var i = iter.start_; i < limit; i++) {
+ point = arr[i];
+ if (predicate) {
+ while (i < limit && !predicate(arr, i)) {
+ i++;
+ }
+ if (i == limit) break;
+ point = arr[i];
+ }
+
+ if (point.canvasy === null || point.canvasy != point.canvasy) {
+ if (stepPlot && prevCanvasX !== null) {
+ // Draw a horizontal line to the start of the missing data
+ ctx.moveTo(prevCanvasX, prevCanvasY);
+ ctx.lineTo(point.canvasx, prevCanvasY);
+ }
+ prevCanvasX = prevCanvasY = null;
+ } else {
+ isIsolated = false;
+ if (drawGapPoints || !prevCanvasX) {
+ iter.nextIdx_ = i;
+ var peek = iter.next();
+ nextCanvasY = iter.hasNext ? iter.peek.canvasy : null;
+
+ var isNextCanvasYNullOrNaN = nextCanvasY === null ||
+ nextCanvasY != nextCanvasY;
+ isIsolated = (!prevCanvasX && isNextCanvasYNullOrNaN);
+ if (drawGapPoints) {
+ // Also consider a point to be "isolated" if it's adjacent to a
+ // null point, excluding the graph edges.
+ if ((!first && !prevCanvasX) ||
+ (iter.hasNext && isNextCanvasYNullOrNaN)) {
+ isIsolated = true;
+ }
+ }
+ }
+
+ if (prevCanvasX !== null) {
+ if (strokeWidth) {
+ if (stepPlot) {
+ ctx.moveTo(prevCanvasX, prevCanvasY);
+ ctx.lineTo(point.canvasx, prevCanvasY);
+ }
+
+ ctx.lineTo(point.canvasx, point.canvasy);
+ }
+ } else {
+ ctx.moveTo(point.canvasx, point.canvasy);
+ }
+ if (drawPoints || isIsolated) {
+ pointsOnLine.push([point.canvasx, point.canvasy]);
+ }
+ prevCanvasX = point.canvasx;
+ prevCanvasY = point.canvasy;