fix: filter out NaN vertices from IFC geometry

web-ifc-three/src/IFC/components/IFCParser.ts

@@ -233,20 +233,92 @@ export class IFCParser implements ParserAPI {
     private ifcGeometryToBuffer(expressID: number, vertexData: Float32Array, indexData: Uint32Array) {
         const geometry = new BufferGeometry();
 
-        const posFloats = new Float32Array(vertexData.length / 2);
-        const normFloats = new Float32Array(vertexData.length / 2);
-        const idAttribute = new Uint32Array(vertexData.length / 6);
+        const numVertices = vertexData.length / 6;
+
+        // First pass: identify valid vertices (no NaN in position) and build index mapping
+        const validFlags = new Uint8Array(numVertices);
+        let validCount = 0;
+        for (let i = 0; i < numVertices; i++) {
+            const x = vertexData[i * 6];
+            const y = vertexData[i * 6 + 1];
+            const z = vertexData[i * 6 + 2];
+            if (Number.isFinite(x) && Number.isFinite(y) && Number.isFinite(z)) {
+                validFlags[i] = 1;
+                validCount++;
+            }
+        }
+
+        // If all vertices are valid, use the fast path (no filtering)
+        if (validCount === numVertices) {
+            const posFloats = new Float32Array(vertexData.length / 2);
+            const normFloats = new Float32Array(vertexData.length / 2);
+            const idAttribute = new Uint32Array(vertexData.length / 6);
+
+            for (let i = 0; i < vertexData.length; i += 6) {
+                posFloats[i / 2] = vertexData[i];
+                posFloats[i / 2 + 1] = vertexData[i + 1];
+                posFloats[i / 2 + 2] = vertexData[i + 2];
+
+                normFloats[i / 2] = vertexData[i + 3];
+                normFloats[i / 2 + 1] = vertexData[i + 4];
+                normFloats[i / 2 + 2] = vertexData[i + 5];
+
+                idAttribute[i / 6] = expressID;
+            }
+
+            geometry.setAttribute(
+                'position',
+                new BufferAttribute(posFloats, 3));
+            geometry.setAttribute(
+                'normal',
+                new BufferAttribute(normFloats, 3));
+            geometry.setAttribute(
+                'expressID',
+                new BufferAttribute(idAttribute, 1));
+
+            geometry.setIndex(new BufferAttribute(indexData, 1));
+            return geometry;
+        }
+
+        // Some vertices have NaN positions — filter them out
+        // Build remapping: old index -> new index
+        const indexRemap = new Uint32Array(numVertices);
+        let nextNewIndex = 0;
+        for (let i = 0; i < numVertices; i++) {
+            if (validFlags[i]) {
+                indexRemap[i] = nextNewIndex++;
+            }
+        }
 
-        for (let i = 0; i < vertexData.length; i += 6) {
-            posFloats[i / 2] = vertexData[i];
-            posFloats[i / 2 + 1] = vertexData[i + 1];
-            posFloats[i / 2 + 2] = vertexData[i + 2];
+        const posFloats = new Float32Array(validCount * 3);
+        const normFloats = new Float32Array(validCount * 3);
+        const idAttribute = new Uint32Array(validCount);
 
-            normFloats[i / 2] = vertexData[i + 3];
-            normFloats[i / 2 + 1] = vertexData[i + 4];
-            normFloats[i / 2 + 2] = vertexData[i + 5];
+        let newVertIdx = 0;
+        for (let i = 0; i < numVertices; i++) {
+            if (!validFlags[i]) continue;
+            posFloats[newVertIdx * 3] = vertexData[i * 6];
+            posFloats[newVertIdx * 3 + 1] = vertexData[i * 6 + 1];
+            posFloats[newVertIdx * 3 + 2] = vertexData[i * 6 + 2];
 
-            idAttribute[i / 6] = expressID;
+            normFloats[newVertIdx * 3] = vertexData[i * 6 + 3];
+            normFloats[newVertIdx * 3 + 1] = vertexData[i * 6 + 4];
+            normFloats[newVertIdx * 3 + 2] = vertexData[i * 6 + 5];
+
+            idAttribute[newVertIdx] = expressID;
+            newVertIdx++;
+        }
+
+        // Remap indices to use new vertex indices, discarding triangles with invalid vertices
+        const filteredIndices: number[] = [];
+        for (let i = 0; i < indexData.length; i += 3) {
+            const a = indexRemap[indexData[i]];
+            const b = indexRemap[indexData[i + 1]];
+            const c = indexRemap[indexData[i + 2]];
+            // Only include the triangle if all three vertices are valid
+            if (validFlags[indexData[i]] && validFlags[indexData[i + 1]] && validFlags[indexData[i + 2]]) {
+                filteredIndices.push(a, b, c);
+            }
         }
 
         geometry.setAttribute(
@@ -259,7 +331,7 @@ export class IFCParser implements ParserAPI {
             'expressID',
             new BufferAttribute(idAttribute, 1));
 
-        geometry.setIndex(new BufferAttribute(indexData, 1));
+        geometry.setIndex(new BufferAttribute(new Uint32Array(filteredIndices), 1));
         return geometry;
     }
 

web-ifc-three/src/IFCLoader.ts

@@ -11,6 +11,13 @@ class IFCLoader extends Loader {
         this.ifcManager = new IFCManager();
     }
 
+    /**
+     * Loads an IFC file from a given URL.
+     * @param url URL of the IFC file or blob URL.
+     * @param onLoad Callback when the IFC model is loaded.
+     * @param onProgress Optional progress callback.
+     * @param onError Optional error callback.
+     */
     load(
         url: any,
         onLoad: (ifc: IFCModel) => void,
@@ -19,6 +26,29 @@ class IFCLoader extends Loader {
     ) {
         const scope = this;
 
+        // Detect JSON files and provide a helpful error message.
+        // Users often try to load JSON files (produced by ifc-to-json) directly,
+        // but web-ifc-three only supports binary IFC files for geometry.
+        const urlString = typeof url === 'string' ? url : '';
+        if (urlString.endsWith('.json')) {
+            const error = new Error(
+                'Cannot load ".json" files directly with IFCLoader. ' +
+                'The IFCLoader is designed to load binary IFC files (.ifc) for geometry. ' +
+                'If you are trying to load a JSON file produced by "ifc-to-json", ' +
+                'please note that JSON files contain property/metadata only (not geometry) ' +
+                'and must be loaded alongside an IFC file using addModelJSONData(). ' +
+                'See the documentation for the correct workflow: ' +
+                'https://ifcjs.github.io/info/docs/Guide/web-ifc/Introduction'
+            );
+            if (onError) {
+                onError(error);
+            } else {
+                console.error(error);
+            }
+            scope.manager.itemError(url);
+            return;
+        }
+
         const loader = new FileLoader(scope.manager);
         this.onProgress = onProgress;
         loader.setPath(scope.path);