Enhanced loadModel() method signature with independent U and V flipping options.

src/webgl/loading.js

@@ -177,6 +177,94 @@ p5.prototype.loadModel = function(path) {
   }
   return model;
 };
+/**
+ * @method loadModel
+ * @param  {String} path
+ * @param  {Object} [options]
+ * @param  {function(p5.Geometry)} [options.successCallback]
+ * @param  {function(Event)} [options.failureCallback]
+ * @param  {String} [options.fileType]
+ * @param  {boolean} [options.normalize]
+ * @return {p5.Geometry} the <a href="#/p5.Geometry">p5.Geometry</a> object
+ */
+p5.prototype.loadModel = function(path,options) {
+  p5._validateParameters('loadModel', arguments);
+  let normalize= false;
+  let successCallback;
+  let failureCallback;
+  let fileType = path.slice(-4);
+  if (options && typeof options === 'object') {
+    normalize = options.normalize || false;
+    successCallback = options.successCallback;
+    failureCallback = options.failureCallback;
+    fileType = options.fileType || fileType;
+  } else if (typeof options === 'boolean') {
+    normalize = options;
+    successCallback = arguments[2];
+    failureCallback = arguments[3];
+    if (typeof arguments[4] !== 'undefined') {
+      fileType = arguments[4];
+    }
+  } else {
+    successCallback = typeof arguments[1] === 'function' ? arguments[1] : undefined;
+    failureCallback = arguments[2];
+    if (typeof arguments[3] !== 'undefined') {
+      fileType = arguments[3];
+    }
+  }
+
+  const model = new p5.Geometry();
+  model.gid = `${path}|${normalize}`;
+  const self = this;
+
+  if (fileType.match(/\.stl$/i)) {
+    this.httpDo(
+      path,
+      'GET',
+      'arrayBuffer',
+      arrayBuffer => {
+        parseSTL(model, arrayBuffer);
+
+        if (normalize) {
+          model.normalize();
+        }
+        self._decrementPreload();
+        if (typeof successCallback === 'function') {
+          successCallback(model);
+        }
+      },
+      failureCallback
+    );
+  } else if (fileType.match(/\.obj$/i)) {
+    this.loadStrings(
+      path,
+      strings => {
+        parseObj(model, strings);
+
+        if (normalize) {
+          model.normalize();
+        }
+
+        self._decrementPreload();
+        if (typeof successCallback === 'function') {
+          successCallback(model);
+        }
+      },
+      failureCallback
+    );
+  } else {
+    p5._friendlyFileLoadError(3, path);
+
+    if (failureCallback) {
+      failureCallback();
+    } else {
+      p5._friendlyError(
+        'Sorry, the file type is invalid. Only OBJ and STL files are supported.'
+      );
+    }
+  }
+  return model;
+};
 
 /**
  * Parse OBJ lines into model. For reference, this is what a simple model of a

src/webgl/p5.Geometry.js

@@ -142,6 +142,24 @@ p5.Geometry = class Geometry {
     this.vertexColors = [];
     return this;
   }
+  flipU() {
+    this.uvs = this.uvs.flat().map((val, index) => {
+      if (index % 2 === 0) {
+        return 1 - val;
+      } else {
+        return val;
+      }
+    });
+  }
+  flipV() {
+    this.uvs = this.uvs.flat().map((val, index) => {
+      if (index % 2 === 0) {
+        return val;
+      } else {
+        return 1 - val;
+      }
+    });
+  }
   /**
  * computes faces for geometry objects based on the vertices.
  * @method computeFaces