Angular Chart with Multi-Style Series

1import {
2    BaseRenderDataTransform,
3    XyyPointSeriesResampled,
4    NumberRange,
5    RenderPassData,
6    IPointSeries,
7    XyDataSeries,
8    SciChartSurface,
9    NumericAxis,
10    TrianglePointMarker,
11    XyScatterRenderableSeries,
12    EllipsePointMarker,
13    PointMarkerDrawingProvider,
14    IXyyPointSeries,
15    IPointMarker,
16    FastColumnRenderableSeries,
17    GradientParams,
18    Point,
19    ColumnSeriesDrawingProvider,
20    ZoomExtentsModifier,
21    MouseWheelZoomModifier,
22    DataPointSelectionModifier,
23    LineSeriesDrawingProvider,
24    FastLineRenderableSeries,
25    ILineSeriesDrawingProviderProperties,
26    ELineDrawMode,
27    OhlcPointSeriesResampled,
28    IOhlcPointSeries,
29    RolloverModifier,
30    IPointMetadata,
31    SeriesInfo,
32    NativeTextAnnotation,
33    ECoordinateMode,
34    EHorizontalAnchorPoint,
35    EVerticalAnchorPoint,
36    IStrokePaletteProvider,
37    parseColorToUIntArgb,
38    EStrokePaletteMode,
39    IRenderableSeries,
40} from "scichart";
41import { appTheme } from "../../../theme";
42
43/**
44 * This transform turns xy data into ohlc.  Unselected points are in y (close).
45 * Selected points in low for pointmarkers, and selected plus points either side in high for lines.
46 * If you only need this for points or columns, you could transform to Xyy instead
47 */
48class SplitRenderDataTransform extends BaseRenderDataTransform<OhlcPointSeriesResampled> {
49    protected createPointSeries(): OhlcPointSeriesResampled {
50        return new OhlcPointSeriesResampled(this.wasmContext, new NumberRange(0, 0));
51    }
52    protected runTransformInternal(renderPassData: RenderPassData): IPointSeries {
53        const { xValues: oldX, yValues: oldY, indexes: oldI, resampled } = renderPassData.pointSeries;
54        // this.pointSeries is the target.  Clear the existing values
55        const { xValues, yValues, highValues, lowValues, indexes } = this.pointSeries;
56        xValues.clear();
57        yValues.clear();
58        highValues.clear();
59        lowValues.clear();
60        indexes.clear();
61        // This shows how to properly handled resampled data, though this is not necessary here.
62        const iStart = resampled ? 0 : renderPassData.indexRange.min;
63        const iEnd = resampled ? oldX.size() - 1 : renderPassData.indexRange?.max;
64        const ds = this.parentSeries.dataSeries as XyDataSeries;
65        let prevSelected = false;
66        for (let i = iStart; i <= iEnd; i++) {
67            const index = resampled ? oldI.get(i) : i;
68            const md = ds.getMetadataAt(index);
69            xValues.push_back(oldX.get(i));
70            indexes.push_back(oldI.get(i));
71            let nextSelected = false;
72            if (i < iEnd) {
73                const nextmd = ds.getMetadataAt(index + 1);
74                nextSelected = nextmd.isSelected;
75            }
76            yValues.push_back(md.isSelected ? NaN : oldY.get(i));
77            // For pointmarkers we just need the point itself
78            lowValues.push_back(md.isSelected ? oldY.get(i) : NaN);
79            // need points either side of the selected value for the line to draw.
80            highValues.push_back(prevSelected || md.isSelected || nextSelected ? oldY.get(i) : NaN);
81            prevSelected = md.isSelected;
82        }
83        return this.pointSeries;
84    }
85}
86
87export const drawExample = async (rootElement: string | HTMLDivElement) => {
88    // Create a SciChartSurface
89    const { sciChartSurface, wasmContext } = await SciChartSurface.create(rootElement, {
90        theme: appTheme.SciChartJsTheme,
91    });
92
93    // Create X,Y Axis
94    sciChartSurface.xAxes.add(new NumericAxis(wasmContext, { growBy: new NumberRange(0.05, 0.05) }));
95    sciChartSurface.yAxes.add(new NumericAxis(wasmContext, { growBy: new NumberRange(0, 0.05) }));
96
97    // Column series with different gradient fill for selected columns
98    const xValues = Array.from({ length: 20 }, (x, i) => i);
99    const colyValues = xValues.map((x) => 10 + Math.random() * 40);
100    const colmetadata = xValues.map((x) => ({
101        isSelected: Math.random() < 0.3,
102    }));
103    const columnSeries = new FastColumnRenderableSeries(wasmContext, {
104        fillLinearGradient: new GradientParams(new Point(0, 0), new Point(0, 1), [
105            { color: appTheme.MutedRed, offset: 0 },
106            { color: appTheme.MutedTeal, offset: 1 },
107        ]),
108        dataSeries: new XyDataSeries(wasmContext, {
109            xValues: xValues,
110            yValues: colyValues,
111            metadata: colmetadata,
112            containsNaN: true,
113        }),
114        stroke: "transparent",
115    });
116    // We cannot use a paletteProvider to change a gradient fill, so we have to use a second drawingProvider
117    const selectedColDP = new ColumnSeriesDrawingProvider(
118        wasmContext,
119        columnSeries,
120        // configure this to draw using the selected points
121        (ps) => (ps as IOhlcPointSeries).lowValues
122    );
123    selectedColDP.getProperties = (parentSeries) => {
124        const { stroke, strokeThickness, fill } = parentSeries;
125        return {
126            opacity: 1,
127            // Opacity setting does not currently apply to the gradient colors, so we have to apply it individually
128            fillLinearGradient: new GradientParams(new Point(0, 0), new Point(0, 1), [
129                { color: appTheme.MutedRed + "88", offset: 0 },
130                { color: appTheme.MutedSkyBlue + "88", offset: 1 },
131            ]),
132            stroke,
133            strokeThickness,
134            fill,
135        };
136    };
137    columnSeries.drawingProviders.push(selectedColDP);
138    columnSeries.renderDataTransform = new SplitRenderDataTransform(
139        columnSeries,
140        wasmContext,
141        columnSeries.drawingProviders
142    );
143    sciChartSurface.renderableSeries.add(columnSeries);
144
145    const lineyValues = xValues.map((x) => 30 + x + x * Math.random());
146    const linemetadata = xValues.map((x) => ({
147        isSelected: Math.random() < 0.3,
148    }));
149    // Line series with different pointmarker and dashed line for selected sections
150    const lineSeries = new FastLineRenderableSeries(wasmContext, {
151        dataSeries: new XyDataSeries(wasmContext, {
152            xValues: xValues,
153            yValues: lineyValues,
154            metadata: linemetadata,
155            containsNaN: true,
156        }),
157        pointMarker: new EllipsePointMarker(wasmContext, {
158            width: 14,
159            height: 14,
160            strokeThickness: 0,
161            fill: appTheme.VividSkyBlue,
162        }),
163        stroke: appTheme.VividTeal,
164        strokeThickness: 3,
165        drawNaNAs: ELineDrawMode.DiscontinuousLine,
166    });
167
168    const trianglePM = new TrianglePointMarker(wasmContext, {
169        width: 15,
170        height: 15,
171        strokeThickness: 0,
172        fill: appTheme.VividOrange,
173    });
174    // Additional line drawing for selected segments
175    const selectedLineDP = new LineSeriesDrawingProvider(
176        wasmContext,
177        lineSeries,
178        (ps) => (ps as IOhlcPointSeries).highValues
179    );
180    // Make this drawingProvider used dashed lines
181    selectedLineDP.getProperties = (parentSeries) => {
182        const { stroke, strokeThickness, opacity, isDigitalLine, lineType, drawNaNAs } = parentSeries;
183        return {
184            stroke,
185            strokeThickness,
186            strokeDashArray: [3, 4],
187            isDigitalLine,
188            lineType,
189            drawNaNAs,
190            containsNaN: true,
191        } as ILineSeriesDrawingProviderProperties;
192    };
193    // Add this as the first drawingProviders so it draws behind all pointmarkers
194    lineSeries.drawingProviders.unshift(selectedLineDP);
195
196    // Additional point drawing for selecetd points
197    const triangleDP = new PointMarkerDrawingProvider(
198        wasmContext,
199        lineSeries,
200        (ps) => (ps as IOhlcPointSeries).lowValues
201    );
202    triangleDP.getProperties = (series) => {
203        return { pointMarker: trianglePM as IPointMarker };
204    };
205    lineSeries.drawingProviders.push(triangleDP);
206
207    // Apply the transform to all the drawingProviders
208    lineSeries.renderDataTransform = new SplitRenderDataTransform(lineSeries, wasmContext, lineSeries.drawingProviders);
209    sciChartSurface.renderableSeries.add(lineSeries);
210
211    sciChartSurface.annotations.add(
212        new NativeTextAnnotation({
213            xCoordinateMode: ECoordinateMode.Pixel,
214            yCoordinateMode: ECoordinateMode.Pixel,
215            x1: 20,
216            y1: 20,
217            horizontalAnchorPoint: EHorizontalAnchorPoint.Left,
218            verticalAnchorPoint: EVerticalAnchorPoint.Top,
219            text: "Selected points are styled differently.  Click and drag to change the selection",
220            textColor: appTheme.ForegroundColor,
221            fontSize: 16,
222            opacity: 0.77,
223        })
224    );
225
226    // Optional: Add Interactivity Modifiers
227    sciChartSurface.chartModifiers.add(
228        new DataPointSelectionModifier({
229            allowClickSelect: true,
230            onSelectionChanged: (args) => {
231                lineSeries.renderDataTransform.requiresTransform = true;
232                columnSeries.renderDataTransform.requiresTransform = true;
233            },
234        })
235    );
236    // sciChartSurface.chartModifiers.add(new RolloverModifier({
237    //     tooltipDataTemplate: (seriesInfo: SeriesInfo) => {
238    //         const vals: string[] = [];
239    //         vals.push(`X ${seriesInfo.formattedXValue}`);
240    //         vals.push(`Y ${seriesInfo.formattedYValue}`);
241    //         vals.push(`selected ${(seriesInfo.pointMetadata as IPointMetadata).isSelected}`);
242    //         return vals;
243    //     }
244    // }));
245
246    sciChartSurface.zoomExtents();
247    return { sciChartSurface, wasmContext };
248};
249