fix(front): Revert "Use RawShaderMaterial for transparent objects to improve culling (#532)"

This reverts commit a427b2a.

Author: agviegas

packages/front/src/fragments/IfcStreamer/src/geometry-culler-renderer.ts

@@ -34,13 +34,11 @@ export class GeometryCullerRenderer extends OBC.CullerRenderer {
   private readonly _geometry: THREE.BufferGeometry;
 
   private _material = new THREE.MeshBasicMaterial({
-    transparent: false,
+    transparent: true,
     side: 2,
     opacity: 1,
   });
 
-  private _materialT = new THREE.RawShaderMaterial();
-
   readonly onViewUpdated = new OBC.AsyncEvent<{
     toLoad: { [modelID: string]: Map<number, Set<number>> };
     toRemove: { [modelID: string]: Set<number> };
@@ -291,10 +289,9 @@ export class GeometryCullerRenderer extends OBC.CullerRenderer {
     // Substitute it by fragment with same color
 
     if (!geometry.fragment) {
-      const material = frag.mesh.instanceColor?.array?.[4] !== undefined && frag.mesh.instanceColor.array[4] < 0.9 ? this._materialT : this._material;  
       geometry.fragment = new FRAGS.Fragment(
         frag.mesh.geometry,
-        material,
+        this._material,
         frag.capacity,
       );