DistanceWidget

Source

behavior.js

import macro from 'vtk.js/Sources/macros';

const MAX_POINTS = 2;

export default function widgetBehavior(publicAPI, model) {
  model.classHierarchy.push('vtkDistanceWidgetProp');
  model._isDragging = false;

  // --------------------------------------------------------------------------
  // Display 2D
  // --------------------------------------------------------------------------

  publicAPI.setDisplayCallback = (callback) =>
    model.representations[0].setDisplayCallback(callback);

  // --------------------------------------------------------------------------
  // Interactor events
  // --------------------------------------------------------------------------

  function ignoreKey(e) {
    return e.altKey || e.controlKey || e.shiftKey;
  }

  // --------------------------------------------------------------------------
  // Left press: Select handle to drag
  // --------------------------------------------------------------------------

  publicAPI.handleLeftButtonPress = (e) => {
    if (
      !model.activeState ||
      !model.activeState.getActive() ||
      !model.pickable ||
      ignoreKey(e)
    ) {
      return macro.VOID;
    }
    const manipulator =
      model.activeState?.getManipulator?.() ?? model.manipulator;
    if (
      model.activeState === model.widgetState.getMoveHandle() &&
      model.widgetState.getHandleList().length < MAX_POINTS &&
      manipulator
    ) {
      const { worldCoords } = manipulator.handleEvent(
        e,
        model._apiSpecificRenderWindow
      );
      // Commit handle to location
      const moveHandle = model.widgetState.getMoveHandle();
      moveHandle.setOrigin(...worldCoords);
      const newHandle = model.widgetState.addHandle();
      newHandle.setOrigin(...moveHandle.getOrigin());
      newHandle.setColor(moveHandle.getColor());
      newHandle.setScale1(moveHandle.getScale1());
      newHandle.setManipulator(manipulator);
    } else if (model.dragable) {
      model._isDragging = true;
      model._apiSpecificRenderWindow.setCursor('grabbing');
      model._interactor.requestAnimation(publicAPI);
    }

    publicAPI.invokeStartInteractionEvent();
    return macro.EVENT_ABORT;
  };

  // --------------------------------------------------------------------------
  // Mouse move: Drag selected handle / Handle follow the mouse
  // --------------------------------------------------------------------------

  publicAPI.handleMouseMove = (callData) => {
    const manipulator =
      model.activeState?.getManipulator?.() ?? model.manipulator;
    if (
      manipulator &&
      model.pickable &&
      model.dragable &&
      model.activeState &&
      model.activeState.getActive() &&
      !ignoreKey(callData)
    ) {
      const { worldCoords } = manipulator.handleEvent(
        callData,
        model._apiSpecificRenderWindow
      );

      if (
        worldCoords.length &&
        (model.activeState === model.widgetState.getMoveHandle() ||
          model._isDragging) &&
        model.activeState.setOrigin // e.g. the line is pickable but not draggable
      ) {
        model.activeState.setOrigin(worldCoords);
        publicAPI.invokeInteractionEvent();
        return macro.EVENT_ABORT;
      }
    }

    return macro.VOID;
  };

  // --------------------------------------------------------------------------
  // Left release: Finish drag / Create new handle
  // --------------------------------------------------------------------------

  publicAPI.handleLeftButtonRelease = () => {
    if (
      !model.activeState ||
      !model.activeState.getActive() ||
      !model.pickable
    ) {
      return macro.VOID;
    }
    if (
      model.hasFocus &&
      model.widgetState.getHandleList().length === MAX_POINTS
    ) {
      publicAPI.loseFocus();
      return macro.VOID;
    }

    if (model._isDragging) {
      model._apiSpecificRenderWindow.setCursor('pointer');
      model.widgetState.deactivate();
      model._interactor.cancelAnimation(publicAPI);
      model._isDragging = false;
    } else if (model.activeState !== model.widgetState.getMoveHandle()) {
      model.widgetState.deactivate();
    }

    if (
      (model.hasFocus && !model.activeState) ||
      (model.activeState && !model.activeState.getActive())
    ) {
      model._widgetManager.enablePicking();
      model._interactor.render();
    }

    publicAPI.invokeEndInteractionEvent();
    return macro.EVENT_ABORT;
  };

  // --------------------------------------------------------------------------
  // Focus API - modeHandle follow mouse when widget has focus
  // --------------------------------------------------------------------------

  publicAPI.grabFocus = () => {
    if (
      !model.hasFocus &&
      model.widgetState.getHandleList().length < MAX_POINTS
    ) {
      model.activeState = model.widgetState.getMoveHandle();
      model.activeState.activate();
      model.activeState.setVisible(true);
      model._interactor.requestAnimation(publicAPI);
      publicAPI.invokeStartInteractionEvent();
    }
    model.hasFocus = true;
  };

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

  publicAPI.loseFocus = () => {
    if (model.hasFocus) {
      model._interactor.cancelAnimation(publicAPI);
      publicAPI.invokeEndInteractionEvent();
    }
    model.widgetState.deactivate();
    model.widgetState.getMoveHandle().deactivate();
    model.widgetState.getMoveHandle().setVisible(false);
    model.widgetState.getMoveHandle().setOrigin(null);
    model.activeState = null;
    model.hasFocus = false;
    model._widgetManager.enablePicking();
    model._interactor.render();
  };
}

index.js

import macro from 'vtk.js/Sources/macros';
import vtkAbstractWidgetFactory from 'vtk.js/Sources/Widgets/Core/AbstractWidgetFactory';
import vtkPlanePointManipulator from 'vtk.js/Sources/Widgets/Manipulators/PlaneManipulator';
import vtkPolyLineRepresentation from 'vtk.js/Sources/Widgets/Representations/PolyLineRepresentation';
import vtkSphereHandleRepresentation from 'vtk.js/Sources/Widgets/Representations/SphereHandleRepresentation';
import { distance2BetweenPoints } from 'vtk.js/Sources/Common/Core/Math';

import widgetBehavior from 'vtk.js/Sources/Widgets/Widgets3D/DistanceWidget/behavior';
import stateGenerator from 'vtk.js/Sources/Widgets/Widgets3D/DistanceWidget/state';

import { ViewTypes } from 'vtk.js/Sources/Widgets/Core/WidgetManager/Constants';

// ----------------------------------------------------------------------------
// Factory
// ----------------------------------------------------------------------------

function vtkDistanceWidget(publicAPI, model) {
  model.classHierarchy.push('vtkDistanceWidget');

  const superClass = { ...publicAPI };

  // --- Widget Requirement ---------------------------------------------------

  model.methodsToLink = [
    'activeScaleFactor',
    'activeColor',
    'useActiveColor',
    'glyphResolution',
    'defaultScale',
    'scaleInPixels',
  ];

  publicAPI.getRepresentationsForViewType = (viewType) => {
    switch (viewType) {
      case ViewTypes.DEFAULT:
      case ViewTypes.GEOMETRY:
      case ViewTypes.SLICE:
      case ViewTypes.VOLUME:
      default:
        return [
          { builder: vtkSphereHandleRepresentation, labels: ['handles'] },
          { builder: vtkSphereHandleRepresentation, labels: ['moveHandle'] },
          {
            builder: vtkPolyLineRepresentation,
            labels: ['handles', 'moveHandle'],
          },
        ];
    }
  };

  // --- Public methods -------------------------------------------------------

  publicAPI.getDistance = () => {
    const handles = model.widgetState.getHandleList();
    if (handles.length !== 2) {
      return 0;
    }
    if (!handles[0].getOrigin() || !handles[1].getOrigin()) {
      return 0;
    }
    return Math.sqrt(
      distance2BetweenPoints(handles[0].getOrigin(), handles[1].getOrigin())
    );
  };

  publicAPI.setManipulator = (manipulator) => {
    superClass.setManipulator(manipulator);
    model.widgetState.getMoveHandle().setManipulator(manipulator);
    model.widgetState.getHandleList().forEach((handle) => {
      handle.setManipulator(manipulator);
    });
  };

  // --------------------------------------------------------------------------
  // initialization
  // --------------------------------------------------------------------------

  model.widgetState.onBoundsChange((bounds) => {
    const center = [
      (bounds[0] + bounds[1]) * 0.5,
      (bounds[2] + bounds[3]) * 0.5,
      (bounds[4] + bounds[5]) * 0.5,
    ];
    model.widgetState.getMoveHandle().setOrigin(center);
  });

  // Default manipulator
  publicAPI.setManipulator(
    model.manipulator ||
      vtkPlanePointManipulator.newInstance({ useCameraNormal: true })
  );
}

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

const defaultValues = (initialValues) => ({
  // manipulator: null,
  behavior: widgetBehavior,
  widgetState: stateGenerator(),
  ...initialValues,
});

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

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

  vtkAbstractWidgetFactory.extend(publicAPI, model, initialValues);
  macro.setGet(publicAPI, model, ['manipulator']);

  vtkDistanceWidget(publicAPI, model);
}

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

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

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

export default { newInstance, extend };

state.js

import vtkStateBuilder from 'vtk.js/Sources/Widgets/Core/StateBuilder';

export default function generateState() {
  return vtkStateBuilder
    .createBuilder()
    .addStateFromMixin({
      labels: ['moveHandle'],
      mixins: ['origin', 'color', 'scale1', 'visible', 'manipulator'],
      name: 'moveHandle',
      initialValues: {
        scale1: 30,
        visible: false,
      },
    })
    .addDynamicMixinState({
      labels: ['handles'],
      mixins: ['origin', 'color', 'scale1', 'visible', 'manipulator'],
      name: 'handle',
      initialValues: {
        scale1: 30,
      },
    })
    .build();
}