OrientationMarkerWidget

updateMarkerOrientation()

Manually updates the marker’s orientation.

computeViewport()

Returns the computed viewport size. The format is [left bottom right top].

updateViewport()

Updates the orientation widget viewport size.

setEnabled(enabling)

Sets the widget enabled status, i.e. to show the widget or not.

setViewportCorner(vtkOrientationMarkerWidget.Corner)

Sets which corner to put the widget’s viewport. Defaults to
BOTTOM_LEFT.

setViewportSize(sizeFactor)

Sets the viewport size. The sizeFactor should be between 0.0 and 1.0.
It says how much of the main render window to color. Defaults to 0.2.

setMinPixelSize(pixelSize)

Sets the minimum side length, in pixels, for the orientation marker widget
viewport. Defaults to 50.

setMaxPixelSize(pixelSize)

Sets the maximum side length, in pixels, for the orientation marker widget
viewport. Defaults to 200.

Source

Constants.js

const Corners = {
  TOP_LEFT: 'TOP_LEFT',
  TOP_RIGHT: 'TOP_RIGHT',
  BOTTOM_LEFT: 'BOTTOM_LEFT',
  BOTTOM_RIGHT: 'BOTTOM_RIGHT',
};

export default { Corners };

index.js

import macro from 'vtk.js/Sources/macros';
import vtkRenderer from 'vtk.js/Sources/Rendering/Core/Renderer';
import Constants from 'vtk.js/Sources/Interaction/Widgets/OrientationMarkerWidget/Constants';

const { vtkErrorMacro } = macro;
const { Corners } = Constants;

// ----------------------------------------------------------------------------
// vtkOrientationMarkerWidget
// ----------------------------------------------------------------------------

function vtkOrientationMarkerWidget(publicAPI, model) {
  // Set our className
  model.classHierarchy.push('vtkOrientationMarkerWidget');

  const superClass = { ...publicAPI };

  // Private variables

  const previousCameraInput = [];
  const selfRenderer = vtkRenderer.newInstance();
  const resizeObserver = new ResizeObserver((entries) => {
    if (entries.length === 1) {
      publicAPI.updateViewport();
    }
  });
  let interactorUnsubscribe = null;
  let selfSubscription = null;

  publicAPI.computeViewport = () => {
    const [viewXSize, viewYSize] = model.interactor.getView().getSize();
    const minViewSize = Math.min(viewXSize, viewYSize);

    let pixelSize = model.viewportSize * minViewSize;
    // clamp pixel size
    pixelSize = Math.max(
      Math.min(model.minPixelSize, minViewSize),
      Math.min(model.maxPixelSize, pixelSize)
    );

    const xFrac = pixelSize / viewXSize;
    const yFrac = pixelSize / viewYSize;
    // [left bottom right top]
    switch (model.viewportCorner) {
      case Corners.TOP_LEFT:
        return [0, 1 - yFrac, xFrac, 1];
      case Corners.TOP_RIGHT:
        return [1 - xFrac, 1 - yFrac, 1, 1];
      case Corners.BOTTOM_LEFT:
        return [0, 0, xFrac, yFrac];
      case Corners.BOTTOM_RIGHT:
        return [1 - xFrac, 0, 1, yFrac];
      default:
        vtkErrorMacro('Invalid widget corner');
        return null;
    }
  };

  publicAPI.updateViewport = () => {
    selfRenderer.setViewport(...publicAPI.computeViewport());
    model.interactor.render();
  };

  publicAPI.updateMarkerOrientation = () => {
    const currentCamera = model.interactor
      .findPokedRenderer()
      .getActiveCamera();

    if (!currentCamera) {
      return;
    }

    const position = currentCamera.getReferenceByName('position');
    const focalPoint = currentCamera.getReferenceByName('focalPoint');
    const viewUp = currentCamera.getReferenceByName('viewUp');
    if (
      previousCameraInput[0] !== position[0] ||
      previousCameraInput[1] !== position[1] ||
      previousCameraInput[2] !== position[2] ||
      previousCameraInput[3] !== focalPoint[0] ||
      previousCameraInput[4] !== focalPoint[1] ||
      previousCameraInput[5] !== focalPoint[2] ||
      previousCameraInput[6] !== viewUp[0] ||
      previousCameraInput[7] !== viewUp[1] ||
      previousCameraInput[8] !== viewUp[2]
    ) {
      previousCameraInput[0] = position[0];
      previousCameraInput[1] = position[1];
      previousCameraInput[2] = position[2];
      previousCameraInput[3] = focalPoint[0];
      previousCameraInput[4] = focalPoint[1];
      previousCameraInput[5] = focalPoint[2];
      previousCameraInput[6] = viewUp[0];
      previousCameraInput[7] = viewUp[1];
      previousCameraInput[8] = viewUp[2];
      const activeCamera = selfRenderer.getActiveCamera();
      activeCamera.setPosition(position[0], position[1], position[2]);
      activeCamera.setFocalPoint(focalPoint[0], focalPoint[1], focalPoint[2]);
      activeCamera.setViewUp(viewUp[0], viewUp[1], viewUp[2]);
      selfRenderer.resetCamera();
    }
  };

  /**
   * Enables/Disables the orientation marker.
   */
  publicAPI.setEnabled = (enabling) => {
    if (enabling) {
      if (model.enabled) {
        return;
      }

      if (!model.actor) {
        vtkErrorMacro('Must set actor before enabling orientation marker.');
        return;
      }

      if (!model.interactor) {
        vtkErrorMacro(
          'Must set interactor before enabling orientation marker.'
        );
        return;
      }

      const renderWindow = model.interactor
        .findPokedRenderer()
        .getRenderWindow();
      renderWindow.addRenderer(selfRenderer);
      if (renderWindow.getNumberOfLayers() < 2) {
        renderWindow.setNumberOfLayers(2);
      }
      // Highest number is foreground
      selfRenderer.setLayer(renderWindow.getNumberOfLayers() - 1);
      selfRenderer.setInteractive(false);

      selfRenderer.addViewProp(model.actor);
      model.actor.setVisibility(true);

      ({ unsubscribe: interactorUnsubscribe } = model.interactor.onAnimation(
        publicAPI.updateMarkerOrientation
      ));

      resizeObserver.observe(model.interactor.getView().getCanvas());

      publicAPI.updateViewport();
      publicAPI.updateMarkerOrientation();

      model.enabled = true;
    } else {
      if (!model.enabled) {
        return;
      }
      model.enabled = false;

      resizeObserver.disconnect();
      interactorUnsubscribe();
      interactorUnsubscribe = null;

      model.actor.setVisibility(false);
      selfRenderer.removeViewProp(model.actor);

      const renderWindow = model.interactor
        .findPokedRenderer()
        .getRenderWindow();
      if (renderWindow) {
        renderWindow.removeRenderer(selfRenderer);
      }
    }
    publicAPI.modified();
  };

  /**
   * Sets the viewport corner.
   */
  publicAPI.setViewportCorner = (corner) => {
    if (corner === model.viewportCorner) {
      return;
    }

    model.viewportCorner = corner;
    if (model.enabled) {
      publicAPI.updateViewport();
    }
  };

  /**
   * Sets the viewport size.
   */
  publicAPI.setViewportSize = (sizeFactor) => {
    const viewportSize = Math.min(1, Math.max(0, sizeFactor));
    if (viewportSize === model.viewportSize) {
      return;
    }

    model.viewportSize = viewportSize;
    if (model.enabled) {
      publicAPI.updateViewport();
    }
  };

  publicAPI.setActor = (actor) => {
    const previousState = model.enabled;
    publicAPI.setEnabled(false);
    model.actor = actor;
    publicAPI.setEnabled(previousState);
  };

  publicAPI.getRenderer = () => selfRenderer;

  publicAPI.delete = () => {
    superClass.delete();
    if (selfSubscription) {
      selfSubscription.unsubscribe();
      selfSubscription = null;
    }
    if (interactorUnsubscribe) {
      interactorUnsubscribe();
      interactorUnsubscribe = null;
    }
    resizeObserver.disconnect();
  };

  // --------------------------------------------------------------------------

  // update viewport whenever we are updated
  selfSubscription = publicAPI.onModified(publicAPI.updateViewport);
}

// ----------------------------------------------------------------------------
// Object factory
// ----------------------------------------------------------------------------

export const DEFAULT_VALUES = {
  // actor: null,
  // interactor: null,
  viewportCorner: Constants.Corners.BOTTOM_LEFT,
  viewportSize: 0.2,
  minPixelSize: 50,
  maxPixelSize: 200,
};

// ----------------------------------------------------------------------------

export function extend(publicAPI, model, initialValues = {}) {
  Object.assign(model, DEFAULT_VALUES, initialValues);

  // Build VTK API
  macro.obj(publicAPI, model);

  macro.get(publicAPI, model, ['enabled', 'viewportCorner', 'viewportSize']);

  // NOTE: setting these while the widget is enabled will
  // not update the widget.
  macro.setGet(publicAPI, model, [
    'interactor',
    'minPixelSize',
    'maxPixelSize',
  ]);
  macro.get(publicAPI, model, ['actor']);

  // Object methods
  vtkOrientationMarkerWidget(publicAPI, model);
}

// ----------------------------------------------------------------------------

export const newInstance = macro.newInstance(
  extend,
  'vtkOrientationMarkerWidget'
);

// ----------------------------------------------------------------------------

export default { newInstance, extend, ...Constants };