/**
|
|
*
|
|
* @param {number} start
|
|
* @param {number} end
|
|
* @param {boolean} autoScaleStart
|
|
* @param {boolean} autoScaleEnd
|
|
* @param {number} containerHeight
|
|
* @param {number} majorCharHeight
|
|
* @param {boolean} zeroAlign
|
|
* @param {function} formattingFunction
|
|
* @constructor
|
|
*/
|
|
function DataScale(start, end, autoScaleStart, autoScaleEnd, containerHeight, majorCharHeight, zeroAlign = false, formattingFunction=false) {
|
|
this.majorSteps = [1, 2, 5, 10];
|
|
this.minorSteps = [0.25, 0.5, 1, 2];
|
|
this.customLines = null;
|
|
|
|
this.containerHeight = containerHeight;
|
|
this.majorCharHeight = majorCharHeight;
|
|
this._start = start;
|
|
this._end = end;
|
|
|
|
this.scale = 1;
|
|
this.minorStepIdx = -1;
|
|
this.magnitudefactor = 1;
|
|
this.determineScale();
|
|
|
|
this.zeroAlign = zeroAlign;
|
|
this.autoScaleStart = autoScaleStart;
|
|
this.autoScaleEnd = autoScaleEnd;
|
|
|
|
this.formattingFunction = formattingFunction;
|
|
|
|
if (autoScaleStart || autoScaleEnd) {
|
|
var me = this;
|
|
var roundToMinor = function (value) {
|
|
var rounded = value - (value % (me.magnitudefactor * me.minorSteps[me.minorStepIdx]));
|
|
if (value % (me.magnitudefactor * me.minorSteps[me.minorStepIdx]) > 0.5 * (me.magnitudefactor * me.minorSteps[me.minorStepIdx])) {
|
|
return rounded + (me.magnitudefactor * me.minorSteps[me.minorStepIdx]);
|
|
}
|
|
else {
|
|
return rounded;
|
|
}
|
|
};
|
|
if (autoScaleStart) {
|
|
this._start -= this.magnitudefactor * 2 * this.minorSteps[this.minorStepIdx];
|
|
this._start = roundToMinor(this._start);
|
|
}
|
|
|
|
if (autoScaleEnd) {
|
|
this._end += this.magnitudefactor * this.minorSteps[this.minorStepIdx];
|
|
this._end = roundToMinor(this._end);
|
|
}
|
|
this.determineScale();
|
|
}
|
|
}
|
|
|
|
DataScale.prototype.setCharHeight = function (majorCharHeight) {
|
|
this.majorCharHeight = majorCharHeight;
|
|
};
|
|
|
|
DataScale.prototype.setHeight = function (containerHeight) {
|
|
this.containerHeight = containerHeight;
|
|
};
|
|
|
|
DataScale.prototype.determineScale = function () {
|
|
var range = this._end - this._start;
|
|
this.scale = this.containerHeight / range;
|
|
var minimumStepValue = this.majorCharHeight / this.scale;
|
|
var orderOfMagnitude = (range > 0)
|
|
? Math.round(Math.log(range) / Math.LN10)
|
|
: 0;
|
|
|
|
this.minorStepIdx = -1;
|
|
this.magnitudefactor = Math.pow(10, orderOfMagnitude);
|
|
|
|
var start = 0;
|
|
if (orderOfMagnitude < 0) {
|
|
start = orderOfMagnitude;
|
|
}
|
|
|
|
var solutionFound = false;
|
|
for (var l = start; Math.abs(l) <= Math.abs(orderOfMagnitude); l++) {
|
|
this.magnitudefactor = Math.pow(10, l);
|
|
for (var j = 0; j < this.minorSteps.length; j++) {
|
|
var stepSize = this.magnitudefactor * this.minorSteps[j];
|
|
if (stepSize >= minimumStepValue) {
|
|
solutionFound = true;
|
|
this.minorStepIdx = j;
|
|
break;
|
|
}
|
|
}
|
|
if (solutionFound === true) {
|
|
break;
|
|
}
|
|
}
|
|
};
|
|
|
|
DataScale.prototype.is_major = function (value) {
|
|
return (value % (this.magnitudefactor * this.majorSteps[this.minorStepIdx]) === 0);
|
|
};
|
|
|
|
DataScale.prototype.getStep = function(){
|
|
return this.magnitudefactor * this.minorSteps[this.minorStepIdx];
|
|
};
|
|
|
|
DataScale.prototype.getFirstMajor = function(){
|
|
var majorStep = this.magnitudefactor * this.majorSteps[this.minorStepIdx];
|
|
return this.convertValue(this._start + ((majorStep - (this._start % majorStep)) % majorStep));
|
|
};
|
|
|
|
DataScale.prototype.formatValue = function(current) {
|
|
var returnValue = current.toPrecision(5);
|
|
if (typeof this.formattingFunction === 'function') {
|
|
returnValue = this.formattingFunction(current);
|
|
}
|
|
|
|
if (typeof returnValue === 'number') {
|
|
return '' + returnValue;
|
|
}
|
|
else if (typeof returnValue === 'string') {
|
|
return returnValue;
|
|
}
|
|
else {
|
|
return current.toPrecision(5);
|
|
}
|
|
|
|
};
|
|
|
|
DataScale.prototype.getLines = function () {
|
|
var lines = [];
|
|
var step = this.getStep();
|
|
var bottomOffset = (step - (this._start % step)) % step;
|
|
for (var i = (this._start + bottomOffset); this._end-i > 0.00001; i += step) {
|
|
if (i != this._start) { //Skip the bottom line
|
|
lines.push({major: this.is_major(i), y: this.convertValue(i), val: this.formatValue(i)});
|
|
}
|
|
}
|
|
return lines;
|
|
};
|
|
|
|
DataScale.prototype.followScale = function (other) {
|
|
var oldStepIdx = this.minorStepIdx;
|
|
var oldStart = this._start;
|
|
var oldEnd = this._end;
|
|
|
|
var me = this;
|
|
var increaseMagnitude = function () {
|
|
me.magnitudefactor *= 2;
|
|
};
|
|
var decreaseMagnitude = function () {
|
|
me.magnitudefactor /= 2;
|
|
};
|
|
|
|
if ((other.minorStepIdx <= 1 && this.minorStepIdx <= 1) || (other.minorStepIdx > 1 && this.minorStepIdx > 1)) {
|
|
//easy, no need to change stepIdx nor multiplication factor
|
|
} else if (other.minorStepIdx < this.minorStepIdx) {
|
|
//I'm 5, they are 4 per major.
|
|
this.minorStepIdx = 1;
|
|
if (oldStepIdx == 2) {
|
|
increaseMagnitude();
|
|
} else {
|
|
increaseMagnitude();
|
|
increaseMagnitude();
|
|
}
|
|
} else {
|
|
//I'm 4, they are 5 per major
|
|
this.minorStepIdx = 2;
|
|
if (oldStepIdx == 1) {
|
|
decreaseMagnitude();
|
|
} else {
|
|
decreaseMagnitude();
|
|
decreaseMagnitude();
|
|
}
|
|
}
|
|
|
|
//Get masters stats:
|
|
var otherZero = other.convertValue(0);
|
|
var otherStep = other.getStep() * other.scale;
|
|
|
|
var done = false;
|
|
var count = 0;
|
|
//Loop until magnitude is correct for given constrains.
|
|
while (!done && count++ <5) {
|
|
|
|
//Get my stats:
|
|
this.scale = otherStep / (this.minorSteps[this.minorStepIdx] * this.magnitudefactor);
|
|
var newRange = this.containerHeight / this.scale;
|
|
|
|
//For the case the magnitudefactor has changed:
|
|
this._start = oldStart;
|
|
this._end = this._start + newRange;
|
|
|
|
var myOriginalZero = this._end * this.scale;
|
|
var majorStep = this.magnitudefactor * this.majorSteps[this.minorStepIdx];
|
|
var majorOffset = this.getFirstMajor() - other.getFirstMajor();
|
|
|
|
if (this.zeroAlign) {
|
|
var zeroOffset = otherZero - myOriginalZero;
|
|
this._end += (zeroOffset / this.scale);
|
|
this._start = this._end - newRange;
|
|
} else {
|
|
if (!this.autoScaleStart) {
|
|
this._start += majorStep - (majorOffset / this.scale);
|
|
this._end = this._start + newRange;
|
|
} else {
|
|
this._start -= majorOffset / this.scale;
|
|
this._end = this._start + newRange;
|
|
}
|
|
}
|
|
if (!this.autoScaleEnd && this._end > oldEnd+0.00001) {
|
|
//Need to decrease magnitude to prevent scale overshoot! (end)
|
|
decreaseMagnitude();
|
|
done = false;
|
|
continue;
|
|
}
|
|
if (!this.autoScaleStart && this._start < oldStart-0.00001) {
|
|
if (this.zeroAlign && oldStart >= 0) {
|
|
console.warn("Can't adhere to given 'min' range, due to zeroalign");
|
|
} else {
|
|
//Need to decrease magnitude to prevent scale overshoot! (start)
|
|
decreaseMagnitude();
|
|
done = false;
|
|
continue;
|
|
}
|
|
}
|
|
if (this.autoScaleStart && this.autoScaleEnd && newRange < (oldEnd-oldStart)){
|
|
increaseMagnitude();
|
|
done = false;
|
|
continue;
|
|
}
|
|
done = true;
|
|
}
|
|
};
|
|
|
|
DataScale.prototype.convertValue = function (value) {
|
|
return this.containerHeight - ((value - this._start) * this.scale);
|
|
};
|
|
|
|
DataScale.prototype.screenToValue = function (pixels) {
|
|
return ((this.containerHeight - pixels) / this.scale) + this._start;
|
|
};
|
|
|
|
module.exports = DataScale;
|