support gltf-transform

Author: RenaudRohlinger

README.md

@@ -31,6 +31,9 @@ Note: If you're using an older version of Blender or prefer manual installation,
 2. Import the extension in your Three.js project
 3. Add the extension to your GLTFLoader:
 
+### Support with GLTF-Transform
+`gltf-transform optimize cube.glb cube.glb --config /path/to/gltf-transform-curve.config.mjs`
+
 ```javascript
 import { GLTFLoader } from 'three/examples/jsm/loaders/GLTFLoader.js';
 import { GLTFCurveExtension } from './path/to/GLTFCurveExtension.js';

gltf-transform-curve.config.mjs

@@ -0,0 +1,108 @@
+import { ALL_EXTENSIONS } from '@gltf-transform/extensions';
+import {
+  Extension,
+  PropertyType,
+  ExtensionProperty,
+} from '@gltf-transform/core';
+
+const NAME = 'UTSUBO_curve_extension';
+
+class CurveData extends ExtensionProperty {
+  init() {
+    this.extensionName = NAME;
+    this.propertyType = 'CurveData';
+    this.parentTypes = [PropertyType.NODE];
+    this.splines = [];
+    this.dimensions = '3D';
+  }
+
+  getDefaults() {
+    return {
+      splines: [],
+      dimensions: '3D',
+    };
+  }
+
+  getSplines() {
+    return this.get('splines');
+  }
+
+  setSplines(splines) {
+    return this.set('splines', splines);
+  }
+
+  getDimensions() {
+    return this.get('dimensions');
+  }
+
+  setDimensions(dimensions) {
+    return this.set('dimensions', dimensions);
+  }
+}
+
+class CurveExtension extends Extension {
+  constructor(doc) {
+    super(doc);
+    this.extensionName = NAME;
+    this.propertyType = CurveData;
+  }
+
+  static get EXTENSION_NAME() {
+    return NAME;
+  }
+
+  createCurveData() {
+    return new CurveData(this.document.getGraph());
+  }
+
+  read(context) {
+    const jsonDoc = context.jsonDoc;
+
+    (jsonDoc.json.nodes || []).forEach((nodeDef, nodeIndex) => {
+      if (nodeDef.extensions && nodeDef.extensions[NAME]) {
+        const curveDataDef = nodeDef.extensions[NAME];
+        const curveData = this.createCurveData()
+          .setSplines(curveDataDef.splines)
+          .setDimensions(curveDataDef.dimensions);
+
+        console.log(curveData);
+        const node = context.nodes[nodeIndex];
+        node.setExtension(NAME, curveData);
+      }
+    });
+
+    return this;
+  }
+
+  write(context) {
+    const jsonDoc = context.jsonDoc;
+
+    this.document
+      .getRoot()
+      .listNodes()
+      .forEach((node) => {
+        const curveData = node.getExtension(NAME);
+        if (curveData) {
+          const nodeIndex = context.nodeIndexMap.get(node);
+          const nodeDef = jsonDoc.json.nodes[nodeIndex];
+          nodeDef.extensions = nodeDef.extensions || {};
+          nodeDef.extensions[NAME] = {
+            splines: curveData.getSplines(),
+            dimensions: curveData.getDimensions(),
+          };
+        }
+      });
+
+    // Ensure the extension is listed in extensionsUsed
+    if (!jsonDoc.json.extensionsUsed) {
+      jsonDoc.json.extensionsUsed = [];
+    }
+    if (!jsonDoc.json.extensionsUsed.includes(NAME)) {
+      jsonDoc.json.extensionsUsed.push(NAME);
+    }
+
+    return this;
+  }
+}
+
+export default { extensions: [...ALL_EXTENSIONS, CurveExtension] };