JavaScript Polar Scatter Chart

1import {
2    PolarMouseWheelZoomModifier,
3    PolarZoomExtentsModifier,
4    PolarPanModifier,
5    XyDataSeries,
6    PolarNumericAxis,
7    SciChartPolarSurface,
8    EPolarAxisMode, 
9    NumberRange, 
10    EAxisAlignment, 
11    EPolarLabelMode,
12    PolarXyScatterRenderableSeries,
13    SweepAnimation,
14    EHorizontalTextPosition,
15    EVerticalTextPosition,
16    Thickness,
17    EllipsePointMarker,
18    PolarLegendModifier,
19    EDataLabelSkipMode,
20    TrianglePointMarker,
21    EPointMarkerType,
22    ELegendPlacement,
23    ELegendOrientation,
24    TLegendItem,
25    getLegendItemHtml,
26} from "scichart";
27import { appTheme } from "../../../theme";
28
29export const drawExample = async (rootElement: string | HTMLDivElement) => {
30    const { sciChartSurface, wasmContext } = await SciChartPolarSurface.create(rootElement, {
31        theme: appTheme.SciChartJsTheme,
32    });
33
34    const radialYAxis = new PolarNumericAxis(wasmContext, {
35        polarAxisMode: EPolarAxisMode.Radial,
36        axisAlignment: EAxisAlignment.Right,
37        visibleRange: new NumberRange(0, 1400),
38        zoomExtentsToInitialRange: true,
39        
40        drawMinorTickLines: false,
41        drawMajorTickLines: false,
42        drawMinorGridLines: false,
43        
44        startAngle: Math.PI / 2,
45        majorGridLineStyle: {
46            color: appTheme.DarkIndigo,
47            strokeThickness: 1,
48        },
49        drawLabels: false, // no radial labels
50    });
51    sciChartSurface.yAxes.add(radialYAxis);
52
53    const polarXAxis = new PolarNumericAxis(wasmContext, {
54        polarAxisMode: EPolarAxisMode.Angular,
55        axisAlignment: EAxisAlignment.Top,
56        polarLabelMode: EPolarLabelMode.Parallel,
57        visibleRange: new NumberRange(0, 360),
58        startAngle: Math.PI / 2, // start at 12 o'clock
59        flippedCoordinates: true, // go clockwise
60        zoomExtentsToInitialRange: true,
61
62        autoTicks: false,
63        majorDelta: 30,
64
65        drawMinorTickLines: false,
66        drawMajorTickLines: false,
67        drawMinorGridLines: false,
68
69        useNativeText: true,
70        labelPrecision: 0,
71        labelPostfix: "°",
72        labelStyle: {
73            color: "white",
74        },
75        majorGridLineStyle: {
76            color: appTheme.DarkIndigo,
77            strokeThickness: 1,
78        },
79    });
80    sciChartSurface.xAxes.add(polarXAxis);
81
82    const xValues = Array.from({ length: 540 }, (_, i) => i);
83    const SCATTER_DATA = [
84        {
85            yVals: xValues.map((x) => 2 * x + x * Math.random() * 0.5),
86            color: appTheme.VividOrange,
87            name: "Circle Series",
88            pointMarkerType: EPointMarkerType.Ellipse
89        }, 
90        {
91            yVals: xValues.map((x) => x + x * Math.random() * 0.5),
92            color: appTheme.VividSkyBlue,
93            name: "Triangular Series",
94            pointMarkerType: EPointMarkerType.Triangle,
95        }
96    ]
97
98    SCATTER_DATA.forEach(({ yVals, color, name, pointMarkerType }) => {
99        const polarScatter = new PolarXyScatterRenderableSeries(wasmContext, {
100            dataSeries: new XyDataSeries(wasmContext, {
101                xValues: xValues,
102                yValues: yVals,
103                dataSeriesName: name,
104            }),
105            opacity: 0.7,
106            stroke: color, // set stroke color for Legend modifier markers
107
108            // @ts-ignore
109            pointMarker: {
110                type: pointMarkerType,
111                options: {
112                    width: 10,
113                    height: 10,
114                    stroke: color,
115                    strokeThickness: 1,
116                    fill: color + "88",
117                }
118            },
119            animation: new SweepAnimation({ duration: 800 }),
120        });
121        sciChartSurface.renderableSeries.add(polarScatter);
122    });
123
124    // Extra feature -> Custom legend marker with SVG shapes
125    const customMarkerLegendModifier = new PolarLegendModifier({
126        showCheckboxes: true,
127        showSeriesMarkers: true,
128        backgroundColor: "#66666633"
129    });
130    // override "getLegendItemHTML" to add custom SVG shapes
131    customMarkerLegendModifier.sciChartLegend.getLegendItemHTML = (
132        orientation: ELegendOrientation,
133        showCheckboxes: boolean,
134        showSeriesMarkers: boolean,
135        item: TLegendItem
136    ): string => {
137        const display = orientation === ELegendOrientation.Vertical ? "flex" : "inline-flex";
138        let str = `<span class="scichart__legend-item" style="display: ${display}; align-items: center; margin-right: 4px; padding: 0 4px 0 5px; white-space: nowrap; gap: 5px">`;
139        
140        if (showCheckboxes) {
141            const checked = item.checked ? "checked" : "";
142            str += `<input ${checked} type="checkbox" id="${item.id}">`;
143        }
144        
145        if (showSeriesMarkers) {
146            str += `<svg 
147                xmlns="http://www.w3.org/2000/svg"
148                for="${item.id}" 
149                style="width: 15px; height: 15px;" 
150                viewBox="0 0 24 24"
151                stroke-width="2"
152            >
153                ${(() => {
154                    switch (item.name) {
155                        case SCATTER_DATA[0].name: // Circle
156                            return `<circle cx="12" cy="12" r="9" fill="${item.color + "88"}" stroke="${item.color}"/>`;
157
158                        case SCATTER_DATA[1].name: // Triangle 
159                            return `<polygon points="12,2 22,22 2,22" fill="${item.color + "88"}" stroke="${item.color}"/>`;
160
161                        default: // Others 
162                            return `<rect x="2" y="2" width="20" height="20" fill="${item.color + "88"}" stroke="${item.color}"/>`;
163                    }
164                })()}
165            </svg>`
166        }
167        str += `<label for="${item.id}">${item.name}</label>`;
168        str += `</span>`;
169        return str;
170    };
171
172    sciChartSurface.chartModifiers.add(
173        customMarkerLegendModifier,
174        new PolarPanModifier(),
175        new PolarZoomExtentsModifier(),
176        new PolarMouseWheelZoomModifier(),
177    );
178
179    return { sciChartSurface, wasmContext };
180};