vtkInteractorStyleMPRCrosshairs.js

import macro from 'vtk.js/Sources/macro';
import vtkInteractorStyleMPRSlice from './vtkInteractorStyleMPRSlice.js';
import Constants from 'vtk.js/Sources/Rendering/Core/InteractorStyle/Constants';
import vtkCoordinate from 'vtk.js/Sources/Rendering/Core/Coordinate';

const { States } = Constants;

// ----------------------------------------------------------------------------
// Global methods
// ----------------------------------------------------------------------------

// ----------------------------------------------------------------------------
// vtkInteractorStyleMPRCrosshairs methods
// ----------------------------------------------------------------------------

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

  function moveCrosshairs(callData) {
    const { apis, apiIndex } = model;
    const api = apis[apiIndex];

    const pos = callData.position;
    const renderer = callData.pokedRenderer;

    const dPos = vtkCoordinate.newInstance();
    dPos.setCoordinateSystemToDisplay();

    dPos.setValue(pos.x, pos.y, 0);
    let worldPos = dPos.getComputedWorldValue(renderer);

    const camera = renderer.getActiveCamera();
    const directionOfProjection = camera.getDirectionOfProjection();

    const halfSlabThickness = api.getSlabThickness() / 2;

    // Add half of the slab thickness to the world position, such that we select
    // The center of the slice.

    for (let i = 0; i < worldPos.length; i++) {
      worldPos[i] += halfSlabThickness * directionOfProjection[i];
    }

    api.svgWidgets.crosshairsWidget.moveCrosshairs(worldPos, apis, apiIndex);

    publicAPI.invokeInteractionEvent({ type: 'InteractionEvent' });
  }

  const superHandleMouseMove = publicAPI.handleMouseMove;
  publicAPI.handleMouseMove = callData => {
    if (model.state === States.IS_WINDOW_LEVEL) {
      moveCrosshairs(callData);
    }

    if (superHandleMouseMove) {
      superHandleMouseMove(callData);
    }
  };

  const superHandleLeftButtonPress = publicAPI.handleLeftButtonPress;
  publicAPI.handleLeftButtonPress = callData => {
    if (!callData.shiftKey && !callData.controlKey) {
      if (model.volumeActor) {
        moveCrosshairs(callData);
        publicAPI.startWindowLevel();
      }
    } else if (superHandleLeftButtonPress) {
      superHandleLeftButtonPress(callData);
    }
  };

  publicAPI.superHandleLeftButtonRelease = publicAPI.handleLeftButtonRelease;
  publicAPI.handleLeftButtonRelease = () => {
    switch (model.state) {
      case States.IS_WINDOW_LEVEL:
        publicAPI.endWindowLevel();
        break;

      default:
        publicAPI.superHandleLeftButtonRelease();
        break;
    }
  };
}

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

const DEFAULT_VALUES = {};

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

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

  // Inheritance
  vtkInteractorStyleMPRSlice.extend(publicAPI, model, initialValues);

  macro.setGet(publicAPI, model, ['callback', 'apis', 'apiIndex', 'onScroll']);

  // Object specific methods
  vtkInteractorStyleMPRCrosshairs(publicAPI, model);
}

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

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

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

export default Object.assign({ newInstance, extend });