scichart
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Fast WebGL JavaScript Charting Library and Framework
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JavaScript
;
var __extends = (this && this.__extends) || (function () {
var extendStatics = function (d, b) {
extendStatics = Object.setPrototypeOf ||
({ __proto__: [] } instanceof Array && function (d, b) { d.__proto__ = b; }) ||
function (d, b) { for (var p in b) if (Object.prototype.hasOwnProperty.call(b, p)) d[p] = b[p]; };
return extendStatics(d, b);
};
return function (d, b) {
if (typeof b !== "function" && b !== null)
throw new TypeError("Class extends value " + String(b) + " is not a constructor or null");
extendStatics(d, b);
function __() { this.constructor = d; }
d.prototype = b === null ? Object.create(b) : (__.prototype = b.prototype, new __());
};
})();
Object.defineProperty(exports, "__esModule", { value: true });
exports.LogarithmicCoordinateCalculator = void 0;
var NumberRange_1 = require("../../../Core/NumberRange");
var XyDirection_1 = require("../../../types/XyDirection");
var CoordinateCalculatorBase_1 = require("./CoordinateCalculatorBase");
/**
* Provides an implementation of Numeric {@link CoordinateCalculatorBase | Coordinate Calculator} which transforms
* numeric data-values to pixel coordinates using logarithmic scaling and vice versa.
* @remarks
* SciChart's {@link https://www.scichart.com/javascript-chart-features | JavaScript Charts} perform conversion operations between
* data-coordinates for all drawing and axis measurements.
*
* You can fetch a CoordinateCalculator instance by calling {@link AxisCore.getCurrentCoordinateCalculator}. This will return a unique calculator
* for the current draw pass.
*
* You can convert pixel to data-coordinates and back by using the following code:
* ```ts
* const axis: AxisCore;
* const calc = axis.getCurrentCoordinateCalculator();
*
* const pixel = calc.getCoordinate(1.23); // Gets the pixel coordinate for data-value 1.23
* const dataValue = cald.getDataValue(pixel); // Performs the inverse operation to get data-value
* ```
*
* Use the Coordinate calculators when drawing, placing markers, annotations or if you want to place a tooltip over the chart.
*/
var LogarithmicCoordinateCalculator = /** @class */ (function (_super) {
__extends(LogarithmicCoordinateCalculator, _super);
/**
* Creates an instance of LogarithmicCoordinateCalculator
* @param webAssemblyContext The {@link TSciChart | SciChart 2D WebAssembly Context} or {@link TSciChart2D | SciChart 2D WebAssembly Context}
* containing native methods and access to our WebGL2 Engine and WebAssembly numerical methods
* @param viewportDimension The size of the associated {@link AxisCore | Axis} at the time of drawing
* @param visibleMin The {@link AxisCore.visibleRange}.min at the time of drawing
* @param visibleMax The {@link AxisCore.visibleRange}.max at the time of drawing
* @param xyDirection Whether the parent axis is an X or Y axis
* @param logBase The Logarithmic base, e.g. 10, for calculating log coordinates
* @param flipCoordinates Whether the flip-coordinates flag is true on the associated axis
* @param offset A constant pixel offset used in coordinate calculations
*/
function LogarithmicCoordinateCalculator(webAssemblyContext, viewportDimension, visibleMin, visibleMax, xyDirection, logBase, flipCoordinates, offset) {
if (offset === void 0) { offset = 0; }
var _this = this;
var isXAxis = xyDirection === XyDirection_1.EXyDirection.XDirection;
_this = _super.call(this, webAssemblyContext, viewportDimension, visibleMin, visibleMax, offset, flipCoordinates) || this;
_this.logBaseProperty = logBase;
_this.nativeCalculator = flipCoordinates
? new webAssemblyContext.FlippedLogarithmicCoordinateCalculator(_this.viewportDimension, _this.visibleMin, _this.visibleMax, -1, _this.offset, _this.logBase)
: new webAssemblyContext.LogarithmicCoordinateCalculator(_this.viewportDimension, _this.visibleMin, _this.visibleMax, -1, _this.offset, _this.logBase);
return _this;
}
Object.defineProperty(LogarithmicCoordinateCalculator.prototype, "logBase", {
get: function () {
return this.logBaseProperty;
},
enumerable: false,
configurable: true
});
LogarithmicCoordinateCalculator.prototype.translateBy = function (pixels, range) {
if (pixels === 0) {
return range;
}
var zeroPoint = Math.abs(this.nativeCalculator.GetDataValue(0));
var toScrollPoint = Math.abs(this.nativeCalculator.GetDataValue(pixels));
var numberUtil = this.webAssemblyContext.NumberUtil;
var isNegative = range.min < 0;
if (isNegative) {
range = new NumberRange_1.NumberRange(Math.abs(range.max), Math.abs(range.min));
}
var expDelta = numberUtil.Log(toScrollPoint, this.logBase) - numberUtil.Log(zeroPoint, this.logBase);
if (this.hasFlippedCoordinates)
expDelta = -expDelta;
var expMin = numberUtil.Log(range.min, this.logBase);
var expMax = numberUtil.Log(range.max, this.logBase);
var newMin = Math.pow(this.logBase, expMin + expDelta);
var newMax = Math.pow(this.logBase, expMax + expDelta);
if (isNegative)
return new NumberRange_1.NumberRange(-newMax, -newMin);
else
return new NumberRange_1.NumberRange(newMin, newMax);
};
LogarithmicCoordinateCalculator.prototype.zoomTranslateBy = function (minFraction, maxFraction, inputRange) {
return inputRange.growByLog(new NumberRange_1.NumberRange(minFraction, maxFraction), this.logBase);
};
return LogarithmicCoordinateCalculator;
}(CoordinateCalculatorBase_1.CoordinateCalculatorBase));
exports.LogarithmicCoordinateCalculator = LogarithmicCoordinateCalculator;