Chart.js/src/controllers/controller.line.js
2019-01-08 16:50:33 +01:00

341 lines
11 KiB
JavaScript

'use strict';
var DatasetController = require('../core/core.datasetController');
var defaults = require('../core/core.defaults');
var elements = require('../elements/index');
var helpers = require('../helpers/index');
var valueOrDefault = helpers.valueOrDefault;
var resolve = helpers.options.resolve;
var isPointInArea = helpers.canvas._isPointInArea;
defaults._set('line', {
showLines: true,
spanGaps: false,
hover: {
mode: 'label'
},
scales: {
xAxes: [{
type: 'category',
id: 'x-axis-0'
}],
yAxes: [{
type: 'linear',
id: 'y-axis-0'
}]
}
});
function lineEnabled(dataset, options) {
return valueOrDefault(dataset.showLine, options.showLines);
}
module.exports = DatasetController.extend({
datasetElementType: elements.Line,
dataElementType: elements.Point,
update: function(reset) {
var me = this;
var meta = me.getMeta();
var line = meta.dataset;
var points = meta.data || [];
var options = me.chart.options;
var lineElementOptions = options.elements.line;
var scale = me.getScaleForId(meta.yAxisID);
var i, ilen, custom;
var dataset = me.getDataset();
var showLine = lineEnabled(dataset, options);
// Update Line
if (showLine) {
custom = line.custom || {};
// Compatibility: If the properties are defined with only the old name, use those values
if ((dataset.tension !== undefined) && (dataset.lineTension === undefined)) {
dataset.lineTension = dataset.tension;
}
// Utility
line._scale = scale;
line._datasetIndex = me.index;
// Data
line._children = points;
// Model
line._model = {
// Appearance
// The default behavior of lines is to break at null values, according
// to https://github.com/chartjs/Chart.js/issues/2435#issuecomment-216718158
// This option gives lines the ability to span gaps
spanGaps: valueOrDefault(dataset.spanGaps, options.spanGaps),
tension: resolve([custom.tension, dataset.lineTension, lineElementOptions.tension]),
backgroundColor: resolve([custom.backgroundColor, dataset.backgroundColor, lineElementOptions.backgroundColor]),
borderWidth: resolve([custom.borderWidth, dataset.borderWidth, lineElementOptions.borderWidth]),
borderColor: resolve([custom.borderColor, dataset.borderColor, lineElementOptions.borderColor]),
borderCapStyle: resolve([custom.borderCapStyle, dataset.borderCapStyle, lineElementOptions.borderCapStyle]),
borderDash: resolve([custom.borderDash, dataset.borderDash, lineElementOptions.borderDash]),
borderDashOffset: resolve([custom.borderDashOffset, dataset.borderDashOffset, lineElementOptions.borderDashOffset]),
borderJoinStyle: resolve([custom.borderJoinStyle, dataset.borderJoinStyle, lineElementOptions.borderJoinStyle]),
fill: resolve([custom.fill, dataset.fill, lineElementOptions.fill]),
steppedLine: resolve([custom.steppedLine, dataset.steppedLine, lineElementOptions.stepped]),
cubicInterpolationMode: resolve([custom.cubicInterpolationMode, dataset.cubicInterpolationMode, lineElementOptions.cubicInterpolationMode]),
};
line.pivot();
}
// Update Points
for (i = 0, ilen = points.length; i < ilen; ++i) {
me.updateElement(points[i], i, reset);
}
if (showLine && line._model.tension !== 0) {
me.updateBezierControlPoints();
}
// Now pivot the point for animation
for (i = 0, ilen = points.length; i < ilen; ++i) {
points[i].pivot();
}
},
getPointBackgroundColor: function(point, index) {
var dataset = this.getDataset();
var custom = point.custom || {};
return resolve([
custom.backgroundColor,
dataset.pointBackgroundColor,
dataset.backgroundColor,
this.chart.options.elements.point.backgroundColor
], undefined, index);
},
getPointBorderColor: function(point, index) {
var dataset = this.getDataset();
var custom = point.custom || {};
return resolve([
custom.borderColor,
dataset.pointBorderColor,
dataset.borderColor,
this.chart.options.elements.point.borderColor
], undefined, index);
},
getPointBorderWidth: function(point, index) {
var dataset = this.getDataset();
var custom = point.custom || {};
return resolve([
custom.borderWidth,
dataset.pointBorderWidth,
dataset.borderWidth,
this.chart.options.elements.point.borderWidth
], undefined, index);
},
getPointRotation: function(point, index) {
var custom = point.custom || {};
return resolve([
custom.rotation,
this.getDataset().pointRotation,
this.chart.options.elements.point.rotation
], undefined, index);
},
updateElement: function(point, index, reset) {
var me = this;
var meta = me.getMeta();
var custom = point.custom || {};
var dataset = me.getDataset();
var datasetIndex = me.index;
var value = dataset.data[index];
var yScale = me.getScaleForId(meta.yAxisID);
var xScale = me.getScaleForId(meta.xAxisID);
var pointOptions = me.chart.options.elements.point;
var x, y;
// Compatibility: If the properties are defined with only the old name, use those values
if ((dataset.radius !== undefined) && (dataset.pointRadius === undefined)) {
dataset.pointRadius = dataset.radius;
}
if ((dataset.hitRadius !== undefined) && (dataset.pointHitRadius === undefined)) {
dataset.pointHitRadius = dataset.hitRadius;
}
x = xScale.getPixelForValue(typeof value === 'object' ? value : NaN, index, datasetIndex);
y = reset ? yScale.getBasePixel() : me.calculatePointY(value, index, datasetIndex);
// Utility
point._xScale = xScale;
point._yScale = yScale;
point._datasetIndex = datasetIndex;
point._index = index;
// Desired view properties
point._model = {
x: x,
y: y,
skip: custom.skip || isNaN(x) || isNaN(y),
// Appearance
radius: resolve([custom.radius, dataset.pointRadius, pointOptions.radius], undefined, index),
pointStyle: resolve([custom.pointStyle, dataset.pointStyle, pointOptions.pointStyle], undefined, index),
rotation: me.getPointRotation(point, index),
backgroundColor: me.getPointBackgroundColor(point, index),
borderColor: me.getPointBorderColor(point, index),
borderWidth: me.getPointBorderWidth(point, index),
tension: meta.dataset._model ? meta.dataset._model.tension : 0,
steppedLine: meta.dataset._model ? meta.dataset._model.steppedLine : false,
// Tooltip
hitRadius: resolve([custom.hitRadius, dataset.pointHitRadius, pointOptions.hitRadius], undefined, index)
};
},
calculatePointY: function(value, index, datasetIndex) {
var me = this;
var chart = me.chart;
var meta = me.getMeta();
var yScale = me.getScaleForId(meta.yAxisID);
var sumPos = 0;
var sumNeg = 0;
var i, ds, dsMeta;
if (yScale.options.stacked) {
for (i = 0; i < datasetIndex; i++) {
ds = chart.data.datasets[i];
dsMeta = chart.getDatasetMeta(i);
if (dsMeta.type === 'line' && dsMeta.yAxisID === yScale.id && chart.isDatasetVisible(i)) {
var stackedRightValue = Number(yScale.getRightValue(ds.data[index]));
if (stackedRightValue < 0) {
sumNeg += stackedRightValue || 0;
} else {
sumPos += stackedRightValue || 0;
}
}
}
var rightValue = Number(yScale.getRightValue(value));
if (rightValue < 0) {
return yScale.getPixelForValue(sumNeg + rightValue);
}
return yScale.getPixelForValue(sumPos + rightValue);
}
return yScale.getPixelForValue(value);
},
updateBezierControlPoints: function() {
var me = this;
var chart = me.chart;
var meta = me.getMeta();
var lineModel = meta.dataset._model;
var area = chart.chartArea;
var points = meta.data || [];
var i, ilen, point, model, controlPoints;
// Only consider points that are drawn in case the spanGaps option is used
if (lineModel.spanGaps) {
points = points.filter(function(pt) {
return !pt._model.skip;
});
}
function capControlPoint(pt, min, max) {
return Math.max(Math.min(pt, max), min);
}
if (lineModel.cubicInterpolationMode === 'monotone') {
helpers.splineCurveMonotone(points);
} else {
for (i = 0, ilen = points.length; i < ilen; ++i) {
point = points[i];
model = point._model;
controlPoints = helpers.splineCurve(
helpers.previousItem(points, i)._model,
model,
helpers.nextItem(points, i)._model,
lineModel.tension
);
model.controlPointPreviousX = controlPoints.previous.x;
model.controlPointPreviousY = controlPoints.previous.y;
model.controlPointNextX = controlPoints.next.x;
model.controlPointNextY = controlPoints.next.y;
}
}
if (chart.options.elements.line.capBezierPoints) {
for (i = 0, ilen = points.length; i < ilen; ++i) {
model = points[i]._model;
if (isPointInArea(model, area)) {
if (i > 0 && isPointInArea(points[i - 1]._model, area)) {
model.controlPointPreviousX = capControlPoint(model.controlPointPreviousX, area.left, area.right);
model.controlPointPreviousY = capControlPoint(model.controlPointPreviousY, area.top, area.bottom);
}
if (i < points.length - 1 && isPointInArea(points[i + 1]._model, area)) {
model.controlPointNextX = capControlPoint(model.controlPointNextX, area.left, area.right);
model.controlPointNextY = capControlPoint(model.controlPointNextY, area.top, area.bottom);
}
}
}
}
},
draw: function() {
var me = this;
var chart = me.chart;
var meta = me.getMeta();
var points = meta.data || [];
var area = chart.chartArea;
var ilen = points.length;
var halfBorderWidth;
var i = 0;
if (lineEnabled(me.getDataset(), chart.options)) {
halfBorderWidth = (meta.dataset._model.borderWidth || 0) / 2;
helpers.canvas.clipArea(chart.ctx, {
left: area.left,
right: area.right,
top: area.top - halfBorderWidth,
bottom: area.bottom + halfBorderWidth
});
meta.dataset.draw();
helpers.canvas.unclipArea(chart.ctx);
}
// Draw the points
for (; i < ilen; ++i) {
points[i].draw(area);
}
},
setHoverStyle: function(element) {
// Point
var dataset = this.chart.data.datasets[element._datasetIndex];
var index = element._index;
var custom = element.custom || {};
var model = element._model;
var getHoverColor = helpers.getHoverColor;
element.$previousStyle = {
backgroundColor: model.backgroundColor,
borderColor: model.borderColor,
borderWidth: model.borderWidth,
radius: model.radius
};
model.backgroundColor = resolve([custom.hoverBackgroundColor, dataset.pointHoverBackgroundColor, getHoverColor(model.backgroundColor)], undefined, index);
model.borderColor = resolve([custom.hoverBorderColor, dataset.pointHoverBorderColor, getHoverColor(model.borderColor)], undefined, index);
model.borderWidth = resolve([custom.hoverBorderWidth, dataset.pointHoverBorderWidth, model.borderWidth], undefined, index);
model.radius = resolve([custom.hoverRadius, dataset.pointHoverRadius, this.chart.options.elements.point.hoverRadius], undefined, index);
}
});