Pinch Zoom Modifier 3D

Zooming and Panning a Chart in SciChart.js is achieved by moving the SciChart3DSurface.camera to a new location.

The article "The SciChart3DSurface Camera" goes into detail how this camera class works and how to manipulate it programatically to achieve various views.

If you want to add simple Pinch Zooming via Touch to the chart then you can do so using our ChartModifiers API. The PinchZoomModifier3D was added to SciChart.js v3.2 and performs adjustment of the camera radius giving the appearance of the chart zooming.

Declaring an PinchZoomModifier3D

Declaring a PinchZoomModifier3D is as simple as adding one to the SciChart3DSurface.chartModifiers property. This can be done as a single modifier, or as part of a group.

This results in the following behaviour added to the chart.

<div class="wrapper">
    <div id="scichart-root" ></div>
    <div class="titleWrapper">
        <p class="title">SciChart.js 3D Chart Example</p>
        <p class="subTitle">Use Touch to zoom and pan the chart</p>
        <p class="subTitle">Pinch zoom is enabled via PinchZoomModifier3D</p>
    </div>
    <div id="debug-camera">
        <!-- Debug output from camera will be put here -->
    </div>
</div>

body { margin: 0; font-family: Arial; }
.wrapper { width: 100%; height: 100vh; position: relative; }
#scichart-root { width: 100%; height: 100%; position: relative; }
.titleWrapper { position: absolute; width: 100%; top: 35%; text-align: center; pointer-events: none; color: #ffffff77 }
.title { font-size: 20px; }
.subTitle {  font-size: 16px; }
#debug-camera { pointer-events: none; position: absolute; left: 10px; top: 10px; color: #FFFFFF; background: #00000077; padding: 10px; font-size: 13px }

async function pinchZoom3D(divElementId) {
  const {
    SciChart3DSurface,
    NumericAxis3D,
    Vector3,
    SciChartJsNavyTheme,
  } = SciChart;

  // or, for npm, import { SciChart3DSurface, ... } from "scichart"

  // Create a SciChart3DSurface in the host <div id=".." />
  const { wasmContext, sciChart3DSurface } = await SciChart3DSurface.create(divElementId, {
    // Optional theme
    theme: new SciChartJsNavyTheme(),
    // Optional dimensions of the axis cube (X,Y,Z) in World coordinates
    worldDimensions: new Vector3(300, 200, 300),
    // Optional initial camera position and target
    cameraOptions: {
      position: new Vector3(-300, 300, -300),
      target: new Vector3(0, 50, 0),
    }
  });

  // SciChart.js 3D supports only a single x,y,z axis. Declare your axis like this
  sciChart3DSurface.xAxis = new NumericAxis3D(wasmContext, { axisTitle: "X Axis" });
  sciChart3DSurface.yAxis = new NumericAxis3D(wasmContext, { axisTitle: "Y Axis" })
  sciChart3DSurface.zAxis = new NumericAxis3D(wasmContext, { axisTitle: "Z Axis" });

  const camera = sciChart3DSurface.camera;

  // propertyChanged is raised each time any property changes on the camera
  camera.propertyChanged.subscribe((args) => {
    // Log current properties to console. debugOutput returns array of strings
    const cameraDebug = camera.debugOutput();

    // Output the same information to a div on the page
    document.getElementById("debug-camera").innerHTML = cameraDebug.map(line => `<p>${line}</p>`).join("");
  });
  camera.target = new Vector3(0, 60, 0);

  // #region ExampleA
  const { OrbitModifier3D, PinchZoomModifier3D, MouseWheelZoomModifier3D, ResetCamera3DModifier } = SciChart;

  // or for npm: import { OrbitModifier3D, ... } from "scichart"

  // Add multiple behaviours including pinch-zoom to the chart
  sciChart3DSurface.chartModifiers.add(
    new PinchZoomModifier3D(),
    new OrbitModifier3D(),
    new MouseWheelZoomModifier3D(),
    new ResetCamera3DModifier()
  );
  // #endregion
};

pinchZoom3D("scichart-root");