IFC clipping planes makes the viewer to crash!

casamigos17 · August 14, 2023, 3:32pm

Hello folks,
I have an ifc model with 43 material on it:

When I place a clipping plane, the viewer decrease in performance. It takes 30 seconds to orbit the camera in some direction then another 30 seconds to rotate camera again

Is there any setup I should activate in order to clip tons of materials?

Best regards,
Miguel G

Mugen87 · August 15, 2023, 9:28am

Can you please share more information how you define clipping planes in your application? Are you defining them on material or renderer level?

casamigos17 · August 15, 2023, 5:39pm

My bad, I’m using the IFC.js library to create IFCclipping planes:

const clipperIfc = ifcviewer.clipper;
      clipperIfc.active = true;
        const upsidePlaneIFC = clipperIfc.createFromNormalAndCoplanarPoint(
          new Vector3(0, -1, 0),
          new Vector3(
            (box.min.x + box.max.x) / 2,
            box.max.y,
            (box.min.z + box.max.z) / 2
          )
        );
        //1.b) ifcplaneMesh:turn off material
        const mesh = upsidePlaneIFC.planeMesh;
        mesh.material.opacity = 0.0;

and here you can find the source code:

github.com

IFCjs/web-ifc-viewer/blob/530c567c0bf4328d3522a5dae76921aab78dc121/viewer/src/components/display/clipping-planes/clipper.ts#L76


      
          }
          
          createPlane = () => {
            if (!this.enabled) return;
            const intersects = this.context.castRayIfc();
            if (!intersects) return;
            this.createPlaneFromIntersection(intersects);
            this.intersection = undefined;
          };
          
          createFromNormalAndCoplanarPoint = (normal: Vector3, point: Vector3, isPlan = false) => {
            const plane = new IfcPlane(
              this.context,
              point,
              normal,
              this.activateDragging,
              this.deactivateDragging,
              this.planeSize,
              this.edgesEnabled
            );
            plane.isPlan = isPlan;

which use an IfcPlane class:

github.com

IFCjs/web-ifc-viewer/blob/530c567c0bf4328d3522a5dae76921aab78dc121/viewer/src/components/display/clipping-planes/planes.ts#L16


      
            Object3D,
            Plane,
            PlaneGeometry,
            Vector3
          } from 'three';
          import { TransformControls } from 'three/examples/jsm/controls/TransformControls';
          import { IfcComponent } from '../../../base-types';
          import { ClippingEdges } from './clipping-edges';
          import { IfcContext } from '../../context';
          
          export class IfcPlane extends IfcComponent {
            static planeMaterial = IfcPlane.getPlaneMaterial();
            private static hiddenMaterial = IfcPlane.getHiddenMaterial();
            readonly arrowBoundingBox = new Mesh();
            readonly plane: Plane;
            readonly planeMesh: Mesh;
          
            isVisible = true;
            enabled = true;
            edgesActive = true;

which have a “plane” from Three js as props

Mugen87 · August 15, 2023, 5:58pm

Since you are using an IFC component for clipping, you might want to report this performance issue directly at the respective web-ifc repository.

casamigos17 · August 16, 2023, 5:44am

Indeed, I tried the rough three js library, and works well in my Architecture models (+100 materials). Apparently, the issue comes from the IFC clipping commands. Going to report that

Thanks Mugen!