@inweb/viewer-three/src/Viewer/commands/SetDefaultViewPosition.ts

JavaScript library for rendering CAD and BIM files in a browser using Three.js

///////////////////////////////////////////////////////////////////////////////
// Copyright (C) 2002-2025, Open Design Alliance (the "Alliance").
// All rights reserved.
//
// This software and its documentation and related materials are owned by
// the Alliance. The software may only be incorporated into application
// programs owned by members of the Alliance, subject to a signed
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// trade secrets of the Alliance and its suppliers. The software is also
// protected by copyright law and international treaty provisions. Application
// programs incorporating this software must include the following statement
// with their copyright notices:
//
//   This application incorporates Open Design Alliance software pursuant to a
//   license agreement with Open Design Alliance.
//   Open Design Alliance Copyright (C) 2002-2025 by Open Design Alliance.
//   All rights reserved.
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// By use of this software, its documentation or related materials, you
// acknowledge and accept the above terms.
///////////////////////////////////////////////////////////////////////////////

import { Quaternion, Sphere, Vector3 } from "three";
import type { Viewer } from "../Viewer";
import { zoomTo } from "./ZoomTo";

export const defaultViewPositions = {
  front: new Vector3(0, 0, -1),
  back: new Vector3(0, 0, 1),
  left: new Vector3(1, 0, 0),
  right: new Vector3(-1, 0, 0),
  bottom: new Vector3(0, -1, 0),
  top: new Vector3(0, 1, 0),
  se: new Vector3(-1, 1, -1).normalize(),
  sw: new Vector3(1, 1, -1).normalize(),
  ne: new Vector3(-1, 1, 1).normalize(),
  nw: new Vector3(1, 1, 1).normalize(),
};

export function setDefaultViewPosition(viewer: Viewer, position: string): void {
  const extentsCenter = viewer.extents.getCenter(new Vector3());
  const extentsSize = viewer.extents.getBoundingSphere(new Sphere()).radius * 2;

  const upY = new Vector3(0, 1, 0);
  const offsetY = defaultViewPositions[position] || defaultViewPositions["sw"];

  const up = new Vector3().copy(viewer.camera.up);
  const quaternion = new Quaternion().setFromUnitVectors(upY, up);
  const offset = new Vector3().copy(offsetY).applyQuaternion(quaternion);

  const camera = viewer.camera;
  camera.position.copy(offset).multiplyScalar(extentsSize).add(extentsCenter);
  camera.lookAt(extentsCenter);
  camera.updateMatrixWorld();

  viewer.target.copy(extentsCenter);

  viewer.update();
  viewer.emit({ type: "viewposition", data: position });

  zoomTo(viewer, viewer.extents);
}