apexcharts
Version:
A JavaScript Chart Library
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JavaScript
import * as SVG from '@svgdotjs/svg.js'
/*!
* svg.pathmorphing.js - Enables pathmorphing / path animation in svg.js
* @version 0.1.3
*
*
* @copyright (c) 2018 Ulrich-Matthias Schäfer
* @license MIT
*/;
;(function() {
"use strict";
SVG.extend(SVG.PathArray, {
morph: function(fromArray, toArray, pos, stepper, context) {
var startArr = this.parse(fromArray)
, destArr = this.parse(toArray)
var startOffsetM = 0
, destOffsetM = 0
var startOffsetNextM = false
, destOffsetNextM = false
while(true){
// stop if there is no M anymore
if(startOffsetM === false && destOffsetM === false) break
// find the next M in path array
startOffsetNextM = findNextM(startArr, startOffsetM === false ? false : startOffsetM+1)
destOffsetNextM = findNextM( destArr, destOffsetM === false ? false : destOffsetM+1)
// We have to add one M to the startArray
if(startOffsetM === false){
var bbox = new SVG.PathArray(result.start).bbox()
// when the last block had no bounding box we simply take the first M we got
if(bbox.height == 0 || bbox.width == 0){
startOffsetM = startArr.push(startArr[0]) - 1
}else{
// we take the middle of the bbox instead when we got one
startOffsetM = startArr.push( ['M', bbox.x + bbox.width/2, bbox.y + bbox.height/2 ] ) - 1
}
}
// We have to add one M to the destArray
if( destOffsetM === false){
var bbox = new SVG.PathArray(result.dest).bbox()
if(bbox.height == 0 || bbox.width == 0){
destOffsetM = destArr.push(destArr[0]) - 1
}else{
destOffsetM = destArr.push( ['M', bbox.x + bbox.width/2, bbox.y + bbox.height/2 ] ) - 1
}
}
// handle block from M to next M
var result = handleBlock(startArr, startOffsetM, startOffsetNextM, destArr, destOffsetM, destOffsetNextM)
// update the arrays to their new values
startArr = startArr.slice(0, startOffsetM).concat(result.start, startOffsetNextM === false ? [] : startArr.slice(startOffsetNextM))
destArr = destArr.slice(0, destOffsetM).concat(result.dest , destOffsetNextM === false ? [] : destArr.slice( destOffsetNextM))
// update offsets
startOffsetM = startOffsetNextM === false ? false : startOffsetM + result.start.length
destOffsetM = destOffsetNextM === false ? false : destOffsetM + result.dest.length
}
// copy back arrays
this._array = startArr
this.destination = new SVG.PathArray()
this.destination._array = destArr;
const finalArr = this.fromArray(startArr.map(function (from, fromIndex) {
const step = destArr[fromIndex].map((to, toIndex) => {
if (toIndex === 0) return to;
return stepper.step(from[toIndex], destArr[fromIndex][toIndex], pos, context[fromIndex], context);
});
return step;
}));
return finalArr;
}
})
// sorry for the long declaration
// slices out one block (from M to M) and syncronize it so the types and length match
function handleBlock(startArr = [], startOffsetM, startOffsetNextM, destArr, destOffsetM, destOffsetNextM, undefined){
// slice out the block we need
var startArrTemp = startArr.slice(startOffsetM, startOffsetNextM || undefined)
, destArrTemp = destArr.slice( destOffsetM, destOffsetNextM || undefined)
var i = 0
, posStart = {pos:[0,0], start:[0,0]}
, posDest = {pos:[0,0], start:[0,0]}
do{
// convert shorthand types to long form
startArrTemp[i] = simplyfy.call(posStart, startArrTemp[i])
destArrTemp[i] = simplyfy.call(posDest , destArrTemp[i])
// check if both shape types match
// 2 elliptical arc curve commands ('A'), are considered different if the
// flags (large-arc-flag, sweep-flag) don't match
if(startArrTemp[i][0] != destArrTemp[i][0] || startArrTemp[i][0] == 'M' ||
(startArrTemp[i][0] == 'A' &&
(startArrTemp[i][4] != destArrTemp[i][4] || startArrTemp[i][5] != destArrTemp[i][5])
)
) {
// if not, convert shapes to beziere
Array.prototype.splice.apply(startArrTemp, [i, 1].concat(toBeziere.call(posStart, startArrTemp[i])))
Array.prototype.splice.apply(destArrTemp, [i, 1].concat(toBeziere.call(posDest, destArrTemp[i])))
} else {
// only update positions otherwise
startArrTemp[i] = setPosAndReflection.call(posStart, startArrTemp[i])
destArrTemp[i] = setPosAndReflection.call(posDest , destArrTemp[i])
}
// we are at the end at both arrays. stop here
if(++i == startArrTemp.length && i == destArrTemp.length) break
// destArray is longer. Add one element
if(i == startArrTemp.length){
startArrTemp.push([
'C',
posStart.pos[0],
posStart.pos[1],
posStart.pos[0],
posStart.pos[1],
posStart.pos[0],
posStart.pos[1],
])
}
// startArr is longer. Add one element
if(i == destArrTemp.length){
destArrTemp.push([
'C',
posDest.pos[0],
posDest.pos[1],
posDest.pos[0],
posDest.pos[1],
posDest.pos[0],
posDest.pos[1]
])
}
}while(true)
// return the updated block
return {start:startArrTemp, dest:destArrTemp}
}
// converts shorthand types to long form
function simplyfy(val){
switch(val[0]){
case 'z': // shorthand line to start
case 'Z':
val[0] = 'L'
val[1] = this.start[0]
val[2] = this.start[1]
break
case 'H': // shorthand horizontal line
val[0] = 'L'
val[2] = this.pos[1]
break
case 'V': // shorthand vertical line
val[0] = 'L'
val[2] = val[1]
val[1] = this.pos[0]
break
case 'T': // shorthand quadratic beziere
val[0] = 'Q'
val[3] = val[1]
val[4] = val[2]
val[1] = this.reflection[1]
val[2] = this.reflection[0]
break
case 'S': // shorthand cubic beziere
val[0] = 'C'
val[6] = val[4]
val[5] = val[3]
val[4] = val[2]
val[3] = val[1]
val[2] = this.reflection[1]
val[1] = this.reflection[0]
break
}
return val
}
// updates reflection point and current position
function setPosAndReflection(val){
var len = val.length
this.pos = [ val[len-2], val[len-1] ]
if('SCQT'.indexOf(val[0]) != -1)
this.reflection = [ 2 * this.pos[0] - val[len-4], 2 * this.pos[1] - val[len-3] ]
return val
}
// converts all types to cubic beziere
function toBeziere(val){
var retVal = [val]
switch(val[0]){
case 'M': // special handling for M
this.pos = this.start = [val[1], val[2]]
return retVal
case 'L':
val[5] = val[3] = val[1]
val[6] = val[4] = val[2]
val[1] = this.pos[0]
val[2] = this.pos[1]
break
case 'Q':
val[6] = val[4]
val[5] = val[3]
val[4] = val[4] * 1/3 + val[2] * 2/3
val[3] = val[3] * 1/3 + val[1] * 2/3
val[2] = this.pos[1] * 1/3 + val[2] * 2/3
val[1] = this.pos[0] * 1/3 + val[1] * 2/3
break
case 'A':
retVal = arcToBeziere(this.pos, val)
val = retVal[0]
break
}
val[0] = 'C'
this.pos = [val[5], val[6]]
this.reflection = [2 * val[5] - val[3], 2 * val[6] - val[4]]
return retVal
}
// finds the next position of type M
function findNextM(arr = [], offset){
if(offset === false) return false
for(var i = offset, len = arr.length;i < len;++i){
if(arr[i][0] == 'M') return i
}
return false
}
// Convert an arc segment into equivalent cubic Bezier curves
// Depending on the arc, up to 4 curves might be used to represent it since a
// curve gives a good approximation for only a quarter of an ellipse
// The curves are returned as an array of SVG curve commands:
// [ ['C', x1, y1, x2, y2, x, y] ... ]
function arcToBeziere(pos, val) {
// Parameters extraction, handle out-of-range parameters as specified in the SVG spec
// See: https://www.w3.org/TR/SVG11/implnote.html#ArcOutOfRangeParameters
var rx = Math.abs(val[1]), ry = Math.abs(val[2]), xAxisRotation = val[3] % 360
, largeArcFlag = val[4], sweepFlag = val[5], x = val[6], y = val[7]
, A = new SVG.Point(pos), B = new SVG.Point(x, y)
, primedCoord, lambda, mat, k, c, cSquare, t, O, OA, OB, tetaStart, tetaEnd
, deltaTeta, nbSectors, f, arcSegPoints, angle, sinAngle, cosAngle, pt, i, il
, retVal = [], x1, y1, x2, y2
// Ensure radii are non-zero
if(rx === 0 || ry === 0 || (A.x === B.x && A.y === B.y)) {
// treat this arc as a straight line segment
return [['C', A.x, A.y, B.x, B.y, B.x, B.y]]
}
// Ensure radii are large enough using the algorithm provided in the SVG spec
// See: https://www.w3.org/TR/SVG11/implnote.html#ArcCorrectionOutOfRangeRadii
primedCoord = new SVG.Point((A.x-B.x)/2, (A.y-B.y)/2).transform(new SVG.Matrix().rotate(xAxisRotation))
lambda = (primedCoord.x * primedCoord.x) / (rx * rx) + (primedCoord.y * primedCoord.y) / (ry * ry)
if(lambda > 1) {
lambda = Math.sqrt(lambda)
rx = lambda*rx
ry = lambda*ry
}
// To simplify calculations, we make the arc part of a unit circle (rayon is 1) instead of an ellipse
mat = new SVG.Matrix().rotate(xAxisRotation).scale(1/rx, 1/ry).rotate(-xAxisRotation)
A = A.transform(mat)
B = B.transform(mat)
// Calculate the horizontal and vertical distance between the initial and final point of the arc
k = [B.x-A.x, B.y-A.y]
// Find the length of the chord formed by A and B
cSquare = k[0]*k[0] + k[1]*k[1]
c = Math.sqrt(cSquare)
// Calculate the ratios of the horizontal and vertical distance on the length of the chord
k[0] /= c
k[1] /= c
// Calculate the distance between the circle center and the chord midpoint
// using this formula: t = sqrt(r^2 - c^2 / 4)
// where t is the distance between the cirle center and the chord midpoint,
// r is the rayon of the circle and c is the chord length
// From: http://www.ajdesigner.com/phpcircle/circle_segment_chord_t.php
// Because of the imprecision of floating point numbers, cSquare might end
// up being slightly above 4 which would result in a negative radicand
// To prevent that, a test is made before computing the square root
t = (cSquare < 4) ? Math.sqrt(1 - cSquare/4) : 0
// For most situations, there are actually two different ellipses that
// satisfy the constraints imposed by the points A and B, the radii rx and ry,
// and the xAxisRotation
// When the flags largeArcFlag and sweepFlag are equal, it means that the
// second ellipse is used as a solution
// See: https://www.w3.org/TR/SVG/paths.html#PathDataEllipticalArcCommands
if(largeArcFlag === sweepFlag) {
t *= -1
}
// Calculate the coordinates of the center of the circle from the midpoint of the chord
// This is done by multiplying the ratios calculated previously by the distance between
// the circle center and the chord midpoint and using these values to go from the midpoint
// to the center of the circle
// The negative of the vertical distance ratio is used to modify the x coordinate while
// the horizontal distance ratio is used to modify the y coordinate
// That is because the center of the circle is perpendicular to the chord and perpendicular
// lines are negative reciprocals
O = new SVG.Point((B.x+A.x)/2 + t*-k[1], (B.y+A.y)/2 + t*k[0])
// Move the center of the circle at the origin
OA = new SVG.Point(A.x-O.x, A.y-O.y)
OB = new SVG.Point(B.x-O.x, B.y-O.y)
// Calculate the start and end angle
tetaStart = Math.acos(OA.x/Math.sqrt(OA.x*OA.x + OA.y*OA.y))
if (OA.y < 0) {
tetaStart *= -1
}
tetaEnd = Math.acos(OB.x/Math.sqrt(OB.x*OB.x + OB.y*OB.y))
if (OB.y < 0) {
tetaEnd *= -1
}
// If sweep-flag is '1', then the arc will be drawn in a "positive-angle" direction,
// make sure that the end angle is above the start angle
if (sweepFlag && tetaStart > tetaEnd) {
tetaEnd += 2*Math.PI
}
// If sweep-flag is '0', then the arc will be drawn in a "negative-angle" direction,
// make sure that the end angle is below the start angle
if (!sweepFlag && tetaStart < tetaEnd) {
tetaEnd -= 2*Math.PI
}
// Find the number of Bezier curves that are required to represent the arc
// A cubic Bezier curve gives a good enough approximation when representing at most a quarter of a circle
nbSectors = Math.ceil(Math.abs(tetaStart-tetaEnd) * 2/Math.PI)
// Calculate the coordinates of the points of all the Bezier curves required to represent the arc
// For an in-depth explanation of this part see: http://pomax.github.io/bezierinfo/#circles_cubic
arcSegPoints = []
angle = tetaStart
deltaTeta = (tetaEnd-tetaStart)/nbSectors
f = 4*Math.tan(deltaTeta/4)/3
for (i = 0; i <= nbSectors; i++) { // The <= is because a Bezier curve have a start and a endpoint
cosAngle = Math.cos(angle)
sinAngle = Math.sin(angle)
pt = new SVG.Point(O.x+cosAngle, O.y+sinAngle)
arcSegPoints[i] = [new SVG.Point(pt.x+f*sinAngle, pt.y-f*cosAngle), pt, new SVG.Point(pt.x-f*sinAngle, pt.y+f*cosAngle)]
angle += deltaTeta
}
// Remove the first control point of the first segment point and remove the second control point of the last segment point
// These two control points are not used in the approximation of the arc, that is why they are removed
arcSegPoints[0][0] = arcSegPoints[0][1].clone()
arcSegPoints[arcSegPoints.length-1][2] = arcSegPoints[arcSegPoints.length-1][1].clone()
// Revert the transformation that was applied to make the arc part of a unit circle instead of an ellipse
mat = new SVG.Matrix().rotate(xAxisRotation).scale(rx, ry).rotate(-xAxisRotation)
for (i = 0, il = arcSegPoints.length; i < il; i++) {
arcSegPoints[i][0] = arcSegPoints[i][0].transform(mat)
arcSegPoints[i][1] = arcSegPoints[i][1].transform(mat)
arcSegPoints[i][2] = arcSegPoints[i][2].transform(mat)
}
// Convert the segments points to SVG curve commands
for (i = 1, il = arcSegPoints.length; i < il; i++) {
pt = arcSegPoints[i-1][2]
x1 = pt.x
y1 = pt.y
pt = arcSegPoints[i][0]
x2 = pt.x
y2 = pt.y
pt = arcSegPoints[i][1]
x = pt.x
y = pt.y
retVal.push(['C', x1, y1, x2, y2, x, y])
}
return retVal
}
}());