};
/**
- * Returns a function which returns the next index with a renderable point.
- * When connectSeparatedPoints is false, it just returns the next index.
- * But when it's true, the returned function will skip past points with null
- * yvals.
- *
- * @private
+ * Returns a predicate to be used with an iterator, which will
+ * iterate over points appropriately, depending on whether
+ * connectSeparatedPoints is true. When it's false, the predicate will
+ * skip over points with missing yVals.
*/
-DygraphCanvasRenderer.makeNextPointStep_ = function(
- connectSeparatedPoints, points, start, end) {
- if (connectSeparatedPoints) {
- return function(j) {
- while (++j + start < end) {
- if (!(points[start + j].yval === null)) break;
- }
- return j;
- }
- } else {
- return function(j) { return j + 1 };
- }
-};
+DygraphCanvasRenderer._getIteratorPredicate = function(connectSeparatedPoints) {
+ return connectSeparatedPoints ? DygraphCanvasRenderer._predicateThatSkipsEmptyPoints : null;
+}
+
+DygraphCanvasRenderer._predicateThatSkipsEmptyPoints =
+ function(array, idx) { return array[idx].yval !== null; }
DygraphCanvasRenderer.isNullOrNaN_ = function(x) {
return (x === null || isNaN(x));
var drawGapPoints = this.dygraph_.attr_('drawGapEdgePoints', setName);
ctx.save();
+
+ var iter = Dygraph.createIterator(points, firstIndexInSet, setLength,
+ DygraphCanvasRenderer._getIteratorPredicate(this.attr_("connectSeparatedPoints")));
+
if (strokeWidth && !stepPlot && (!strokePattern || strokePattern.length <= 1)) {
- this._drawTrivialLine(ctx, points, setLength, firstIndexInSet, setName, color, strokeWidth, drawPointCallback, pointSize, drawPoints, drawGapPoints);
+ this._drawTrivialLine(ctx, iter, setName, color, strokeWidth, drawPointCallback, pointSize, drawPoints, drawGapPoints);
} else {
- this._drawNonTrivialLine(ctx, points, setLength, firstIndexInSet, setName, color, strokeWidth, strokePattern, drawPointCallback, pointSize, drawPoints, drawGapPoints, stepPlot);
+ this._drawNonTrivialLine(ctx, iter, setName, color, strokeWidth, strokePattern, drawPointCallback, pointSize, drawPoints, drawGapPoints, stepPlot);
}
ctx.restore();
};
+DygraphCanvasRenderer.prototype._drawPointsOnLine = function(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize) {
+ for (var idx = 0; idx < pointsOnLine.length; idx++) {
+ var cb = pointsOnLine[idx];
+ ctx.save();
+ drawPointCallback(
+ this.dygraph_, setName, ctx, cb[0], cb[1], color, pointSize);
+ ctx.restore();
+ }
+}
+
DygraphCanvasRenderer.prototype._drawNonTrivialLine = function(
- ctx, points, setLength, firstIndexInSet, setName, color, strokeWidth, strokePattern, drawPointCallback, pointSize, drawPoints, drawGapPoints, stepPlot) {
+ ctx, iter, setName, color, strokeWidth, strokePattern, drawPointCallback, pointSize, drawPoints, drawGapPoints, stepPlot) {
var prevX = null;
var prevY = null;
var nextY = null;
- var point, nextPoint;
+ var point;
var pointsOnLine = []; // Array of [canvasx, canvasy] pairs.
- var next = DygraphCanvasRenderer.makeNextPointStep_(
- this.attr_('connectSeparatedPoints'), points, firstIndexInSet,
- firstIndexInSet + setLength);
- for (var j = 0; j < setLength; j = next(j)) {
- point = points[firstIndexInSet + j];
- nextY = (next(j) < setLength) ?
- points[firstIndexInSet + next(j)].canvasy : null;
+ var first = true;
+ while(iter.hasNext()) {
+ point = iter.next();
+ nextY = iter.hasNext() ? iter.peek().canvasy : null;
if (DygraphCanvasRenderer.isNullOrNaN_(point.canvasy)) {
if (stepPlot && prevX !== null) {
// Draw a horizontal line to the start of the missing data
if (drawGapPoints) {
// Also consider a point to be is "isolated" if it's adjacent to a
// null point, excluding the graph edges.
- if ((j > 0 && !prevX) ||
- (next(j) < setLength && DygraphCanvasRenderer.isNullOrNaN_(nextY))) {
+ if ((!first && !prevX) ||
+ (iter.hasNext() && DygraphCanvasRenderer.isNullOrNaN_(nextY))) {
isIsolated = true;
}
}
pointsOnLine.push([point.canvasx, point.canvasy]);
}
}
+ first = false;
}
- for (var idx = 0; idx < pointsOnLine.length; idx++) {
- var cb = pointsOnLine[idx];
- ctx.save();
- drawPointCallback(
- this.dygraph_, setName, ctx, cb[0], cb[1], color, pointSize);
- ctx.restore();
- }
+ this._drawPointsOnLine(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize);
};
DygraphCanvasRenderer.prototype._drawTrivialLine = function(
- ctx, points, setLength, firstIndexInSet, setName, color, strokeWidth, drawPointCallback, pointSize, drawPoints, drawGapPoints) {
+ ctx, iter, setName, color, strokeWidth, drawPointCallback, pointSize, drawPoints, drawGapPoints) {
var prevX = null;
var prevY = null;
var nextY = null;
ctx.beginPath();
ctx.strokeStyle = color;
ctx.lineWidth = strokeWidth;
- for (var j = firstIndexInSet; j < firstIndexInSet + setLength; ++j) {
- var point = points[j];
- nextY = (j + 1 < firstIndexInSet + setLength) ? points[j + 1].canvasy : null;
+ 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 {
if (drawGapPoints) {
// Also consider a point to be is "isolated" if it's adjacent to a
// null point, excluding the graph edges.
- if ((j > firstIndexInSet && !prevX) ||
- ((j + 1 < firstIndexInSet + setLength) && DygraphCanvasRenderer.isNullOrNaN_(nextY))) {
+ if ((!first && !prevX) ||
+ (iter.hasNext() && DygraphCanvasRenderer.isNullOrNaN_(nextY))) {
isIsolated = true;
}
}
pointsOnLine.push([point.canvasx, point.canvasy]);
}
}
+ first = false;
}
ctx.stroke();
- for (var idx = 0; idx < pointsOnLine.length; idx++) {
- var cb = pointsOnLine[idx];
- ctx.save();
- drawPointCallback(
- this.dygraph_, setName, ctx, cb[0], cb[1], color, pointSize);
- ctx.restore();
- }
+ this._drawPointsOnLine(ctx, pointsOnLine, drawPointCallback, setName, color, pointSize);
};
DygraphCanvasRenderer.prototype._drawLine = function(ctx, i) {
var stepPlot = this.attr_("stepPlot");
var points = this.layout.points;
var pointsLength = points.length;
- var point, i, j, prevX, prevY, prevYs, color, setName, newYs, err_color, rgb, yscale, axis;
+ var point, i, prevX, prevY, prevYs, color, setName, newYs, err_color, rgb, yscale, axis;
var setNames = this.layout.setNames;
var setCount = setNames.length;
var firstIndexInSet = this.layout.setPointsOffsets[i];
var setLength = this.layout.setPointsLengths[i];
- var afterLastIndexInSet = firstIndexInSet + setLength;
- var next = DygraphCanvasRenderer.makeNextPointStep_(
- this.attr_('connectSeparatedPoints'), points,
- afterLastIndexInSet);
+ var iter = Dygraph.createIterator(points, firstIndexInSet, setLength,
+ DygraphCanvasRenderer._getIteratorPredicate(this.attr_("connectSeparatedPoints")));
// setup graphics context
prevX = NaN;
fillAlpha + ')';
ctx.fillStyle = err_color;
ctx.beginPath();
- for (j = firstIndexInSet; j < afterLastIndexInSet; j = next(j)) {
- point = points[j];
+ while (iter.hasNext()) {
+ point = iter.next();
if (point.name == setName) { // TODO(klausw): this is always true
if (!Dygraph.isOK(point.y)) {
prevX = NaN;
axisY = this.area.h * axisY + this.area.y;
var firstIndexInSet = this.layout.setPointsOffsets[i];
var setLength = this.layout.setPointsLengths[i];
- var afterLastIndexInSet = firstIndexInSet + setLength;
- var next = DygraphCanvasRenderer.makeNextPointStep_(
- this.attr_('connectSeparatedPoints'), points,
- afterLastIndexInSet);
+ var iter = Dygraph.createIterator(points, firstIndexInSet, setLength,
+ DygraphCanvasRenderer._getIteratorPredicate(this.attr_("connectSeparatedPoints")));
// setup graphics context
prevX = NaN;
fillAlpha + ')';
ctx.fillStyle = err_color;
ctx.beginPath();
- for (j = firstIndexInSet; j < afterLastIndexInSet; j = next(j)) {
- point = points[j];
+ while(iter.hasNext()) {
+ point = iter.next();
if (point.name == setName) { // TODO(klausw): this is always true
if (!Dygraph.isOK(point.y)) {
prevX = NaN;