lib/timeline/component/graph2d_types/line.js
var DOMutil = require('../../../DOMutil');
/**
*
* @param {vis.GraphGroup.id} groupId
* @param {Object} options // TODO: Describe options
* @constructor Line
*/
function Line(groupId, options) { // eslint-disable-line no-unused-vars
}
Line.calcPath = function (dataset, group) {
if (dataset != null) {
if (dataset.length > 0) {
var d = [];
// construct path from dataset
if (group.options.interpolation.enabled == true) {
d = Line._catmullRom(dataset, group);
}
else {
d = Line._linear(dataset);
}
return d;
}
}
};
Line.drawIcon = function (group, x, y, iconWidth, iconHeight, framework) {
var fillHeight = iconHeight * 0.5;
var path, fillPath;
var outline = DOMutil.getSVGElement("rect", framework.svgElements, framework.svg);
outline.setAttributeNS(null, "x", x);
outline.setAttributeNS(null, "y", y - fillHeight);
outline.setAttributeNS(null, "width", iconWidth);
outline.setAttributeNS(null, "height", 2 * fillHeight);
outline.setAttributeNS(null, "class", "vis-outline");
path = DOMutil.getSVGElement("path", framework.svgElements, framework.svg);
path.setAttributeNS(null, "class", group.className);
if (group.style !== undefined) {
path.setAttributeNS(null, "style", group.style);
}
path.setAttributeNS(null, "d", "M" + x + "," + y + " L" + (x + iconWidth) + "," + y + "");
if (group.options.shaded.enabled == true) {
fillPath = DOMutil.getSVGElement("path", framework.svgElements, framework.svg);
if (group.options.shaded.orientation == 'top') {
fillPath.setAttributeNS(null, "d", "M" + x + ", " + (y - fillHeight) +
"L" + x + "," + y + " L" + (x + iconWidth) + "," + y + " L" + (x + iconWidth) + "," + (y - fillHeight));
}
else {
fillPath.setAttributeNS(null, "d", "M" + x + "," + y + " " +
"L" + x + "," + (y + fillHeight) + " " +
"L" + (x + iconWidth) + "," + (y + fillHeight) +
"L" + (x + iconWidth) + "," + y);
}
fillPath.setAttributeNS(null, "class", group.className + " vis-icon-fill");
if (group.options.shaded.style !== undefined && group.options.shaded.style !== "") {
fillPath.setAttributeNS(null, "style", group.options.shaded.style);
}
}
if (group.options.drawPoints.enabled == true) {
var groupTemplate = {
style: group.options.drawPoints.style,
styles: group.options.drawPoints.styles,
size: group.options.drawPoints.size,
className: group.className
};
DOMutil.drawPoint(x + 0.5 * iconWidth, y, groupTemplate, framework.svgElements, framework.svg);
}
};
Line.drawShading = function (pathArray, group, subPathArray, framework) {
// append shading to the path
if (group.options.shaded.enabled == true) {
var svgHeight = Number(framework.svg.style.height.replace('px',''));
var fillPath = DOMutil.getSVGElement('path', framework.svgElements, framework.svg);
var type = "L";
if (group.options.interpolation.enabled == true){
type = "C";
}
var dFill;
var zero = 0;
if (group.options.shaded.orientation == 'top') {
zero = 0;
}
else if (group.options.shaded.orientation == 'bottom') {
zero = svgHeight;
}
else {
zero = Math.min(Math.max(0, group.zeroPosition), svgHeight);
}
if (group.options.shaded.orientation == 'group' && (subPathArray != null && subPathArray != undefined)) {
dFill = 'M' + pathArray[0][0]+ ","+pathArray[0][1] + " " +
this.serializePath(pathArray,type,false) +
' L'+ subPathArray[subPathArray.length-1][0]+ "," + subPathArray[subPathArray.length-1][1] + " " +
this.serializePath(subPathArray,type,true) +
subPathArray[0][0]+ ","+subPathArray[0][1] + " Z";
}
else {
dFill = 'M' + pathArray[0][0]+ ","+pathArray[0][1] + " " +
this.serializePath(pathArray,type,false) +
' V' + zero + ' H'+ pathArray[0][0] + " Z";
}
fillPath.setAttributeNS(null, 'class', group.className + ' vis-fill');
if (group.options.shaded.style !== undefined) {
fillPath.setAttributeNS(null, 'style', group.options.shaded.style);
}
fillPath.setAttributeNS(null, 'd', dFill);
}
};
/**
* draw a line graph
*
* @param {Array.<Object>} pathArray
* @param {vis.Group} group
* @param {{svg: Object, svgElements: Array.<Object>, options: Object, groups: Array.<vis.Group>}} framework
*/
Line.draw = function (pathArray, group, framework) {
if (pathArray != null && pathArray != undefined) {
var path = DOMutil.getSVGElement('path', framework.svgElements, framework.svg);
path.setAttributeNS(null, "class", group.className);
if (group.style !== undefined) {
path.setAttributeNS(null, "style", group.style);
}
var type = "L";
if (group.options.interpolation.enabled == true){
type = "C";
}
// copy properties to path for drawing.
path.setAttributeNS(null, 'd', 'M' + pathArray[0][0]+ ","+pathArray[0][1] + " " + this.serializePath(pathArray,type,false));
}
};
Line.serializePath = function(pathArray,type,inverse){
if (pathArray.length < 2){
//Too little data to create a path.
return "";
}
var d = type;
var i;
if (inverse){
for (i = pathArray.length-2; i > 0; i--){
d += pathArray[i][0] + "," + pathArray[i][1] + " ";
}
}
else {
for (i = 1; i < pathArray.length; i++){
d += pathArray[i][0] + "," + pathArray[i][1] + " ";
}
}
return d;
};
/**
* This uses an uniform parametrization of the interpolation algorithm:
* 'On the Parameterization of Catmull-Rom Curves' by Cem Yuksel et al.
* @param {Array.<Object>} data
* @returns {string}
* @private
*/
Line._catmullRomUniform = function (data) {
// catmull rom
var p0, p1, p2, p3, bp1, bp2;
var d = [];
d.push( [ Math.round(data[0].screen_x) , Math.round(data[0].screen_y) ]);
var normalization = 1 / 6;
var length = data.length;
for (var i = 0; i < length - 1; i++) {
p0 = (i == 0) ? data[0] : data[i - 1];
p1 = data[i];
p2 = data[i + 1];
p3 = (i + 2 < length) ? data[i + 2] : p2;
// Catmull-Rom to Cubic Bezier conversion matrix
// 0 1 0 0
// -1/6 1 1/6 0
// 0 1/6 1 -1/6
// 0 0 1 0
// bp0 = { x: p1.x, y: p1.y };
bp1 = {
screen_x: ((-p0.screen_x + 6 * p1.screen_x + p2.screen_x) * normalization),
screen_y: ((-p0.screen_y + 6 * p1.screen_y + p2.screen_y) * normalization)
};
bp2 = {
screen_x: (( p1.screen_x + 6 * p2.screen_x - p3.screen_x) * normalization),
screen_y: (( p1.screen_y + 6 * p2.screen_y - p3.screen_y) * normalization)
};
// bp0 = { x: p2.x, y: p2.y };
d.push( [ bp1.screen_x , bp1.screen_y ]);
d.push( [ bp2.screen_x , bp2.screen_y ]);
d.push( [ p2.screen_x , p2.screen_y ]);
}
return d;
};
/**
* This uses either the chordal or centripetal parameterization of the catmull-rom algorithm.
* By default, the centripetal parameterization is used because this gives the nicest results.
* These parameterizations are relatively heavy because the distance between 4 points have to be calculated.
*
* One optimization can be used to reuse distances since this is a sliding window approach.
* @param {Array.<Object>} data
* @param {vis.GraphGroup} group
* @returns {string}
* @private
*/
Line._catmullRom = function (data, group) {
var alpha = group.options.interpolation.alpha;
if (alpha == 0 || alpha === undefined) {
return this._catmullRomUniform(data);
}
else {
var p0, p1, p2, p3, bp1, bp2, d1, d2, d3, A, B, N, M;
var d3powA, d2powA, d3pow2A, d2pow2A, d1pow2A, d1powA;
var d = [];
d.push( [ Math.round(data[0].screen_x) , Math.round(data[0].screen_y) ]);
var length = data.length;
for (var i = 0; i < length - 1; i++) {
p0 = (i == 0) ? data[0] : data[i - 1];
p1 = data[i];
p2 = data[i + 1];
p3 = (i + 2 < length) ? data[i + 2] : p2;
d1 = Math.sqrt(Math.pow(p0.screen_x - p1.screen_x, 2) + Math.pow(p0.screen_y - p1.screen_y, 2));
d2 = Math.sqrt(Math.pow(p1.screen_x - p2.screen_x, 2) + Math.pow(p1.screen_y - p2.screen_y, 2));
d3 = Math.sqrt(Math.pow(p2.screen_x - p3.screen_x, 2) + Math.pow(p2.screen_y - p3.screen_y, 2));
// Catmull-Rom to Cubic Bezier conversion matrix
// A = 2d1^2a + 3d1^a * d2^a + d3^2a
// B = 2d3^2a + 3d3^a * d2^a + d2^2a
// [ 0 1 0 0 ]
// [ -d2^2a /N A/N d1^2a /N 0 ]
// [ 0 d3^2a /M B/M -d2^2a /M ]
// [ 0 0 1 0 ]
d3powA = Math.pow(d3, alpha);
d3pow2A = Math.pow(d3, 2 * alpha);
d2powA = Math.pow(d2, alpha);
d2pow2A = Math.pow(d2, 2 * alpha);
d1powA = Math.pow(d1, alpha);
d1pow2A = Math.pow(d1, 2 * alpha);
A = 2 * d1pow2A + 3 * d1powA * d2powA + d2pow2A;
B = 2 * d3pow2A + 3 * d3powA * d2powA + d2pow2A;
N = 3 * d1powA * (d1powA + d2powA);
if (N > 0) {
N = 1 / N;
}
M = 3 * d3powA * (d3powA + d2powA);
if (M > 0) {
M = 1 / M;
}
bp1 = {
screen_x: ((-d2pow2A * p0.screen_x + A * p1.screen_x + d1pow2A * p2.screen_x) * N),
screen_y: ((-d2pow2A * p0.screen_y + A * p1.screen_y + d1pow2A * p2.screen_y) * N)
};
bp2 = {
screen_x: (( d3pow2A * p1.screen_x + B * p2.screen_x - d2pow2A * p3.screen_x) * M),
screen_y: (( d3pow2A * p1.screen_y + B * p2.screen_y - d2pow2A * p3.screen_y) * M)
};
if (bp1.screen_x == 0 && bp1.screen_y == 0) {
bp1 = p1;
}
if (bp2.screen_x == 0 && bp2.screen_y == 0) {
bp2 = p2;
}
d.push( [ bp1.screen_x , bp1.screen_y ]);
d.push( [ bp2.screen_x , bp2.screen_y ]);
d.push( [ p2.screen_x , p2.screen_y ]);
}
return d;
}
};
/**
* this generates the SVG path for a linear drawing between datapoints.
* @param {Array.<Object>} data
* @returns {string}
* @private
*/
Line._linear = function (data) {
// linear
var d = [];
for (var i = 0; i < data.length; i++) {
d.push([ data[i].screen_x , data[i].screen_y ]);
}
return d;
};
module.exports = Line;