Merge branch 'master' of https://github.com/BabylonJS/Babylon.js

# Conflicts:
#	Playground/babylon.d.txt
#	dist/preview release/babylon.d.ts
#	dist/preview release/babylon.js
#	dist/preview release/babylon.worker.js
#	dist/preview release/customConfigurations/minimalGLTFViewer/babylon.d.ts
#	dist/preview release/customConfigurations/minimalGLTFViewer/babylon.js
#	dist/preview release/viewer/babylon.viewer.js

Tools/Gulp/package.json

@@ -44,16 +44,14 @@
         "ts-loader": "^2.3.7",
         "typescript": "^2.6.2",
         "webpack-stream": "^4.0.0",
-
         "karma": "^2.0.0",
         "karma-chrome-launcher": "^2.2.0",
         "karma-sauce-launcher": "^1.2.0",
-
         "mocha": "^4.0.1",
         "chai": "^4.1.2",
         "sinon": "^4.1.3",
         "karma-mocha": "^1.3.0",
-        "karma-chai":"^0.1.0",
+        "karma-chai": "^0.1.0",
         "karma-sinon": "^1.0.5"
     },
     "scripts": {

dist/preview release/babylon.max.js

@@ -13585,7 +13585,7 @@ var BABYLON;
          */
         TransformNode.prototype._getWorldMatrixDeterminant = function () {
             if (this._currentRenderId !== this.getScene().getRenderId()) {
-                this._worldMatrixDeterminant = this.computeWorldMatrix().determinant();
+                this.computeWorldMatrix();
             }
             return this._worldMatrixDeterminant;
         };
@@ -14233,6 +14233,8 @@ var BABYLON;
             if (!this._poseMatrix) {
                 this._poseMatrix = BABYLON.Matrix.Invert(this._worldMatrix);
             }
+            // Cache the determinant
+            this._worldMatrixDeterminant = this._worldMatrix.determinant();
             return this._worldMatrix;
         };
         TransformNode.prototype._afterComputeWorldMatrix = function () {

dist/preview release/customConfigurations/minimalGLTFViewer/babylon.max.js

@@ -13585,7 +13585,7 @@ var BABYLON;
          */
         TransformNode.prototype._getWorldMatrixDeterminant = function () {
             if (this._currentRenderId !== this.getScene().getRenderId()) {
-                this._worldMatrixDeterminant = this.computeWorldMatrix().determinant();
+                this.computeWorldMatrix();
             }
             return this._worldMatrixDeterminant;
         };
@@ -14233,6 +14233,8 @@ var BABYLON;
             if (!this._poseMatrix) {
                 this._poseMatrix = BABYLON.Matrix.Invert(this._worldMatrix);
             }
+            // Cache the determinant
+            this._worldMatrixDeterminant = this._worldMatrix.determinant();
             return this._worldMatrix;
         };
         TransformNode.prototype._afterComputeWorldMatrix = function () {

src/Mesh/babylon.transformNode.ts

@@ -119,7 +119,7 @@ module BABYLON {
          */
         protected _getWorldMatrixDeterminant(): number {
             if (this._currentRenderId !== this.getScene().getRenderId()) {
-                this._worldMatrixDeterminant = this.computeWorldMatrix().determinant();
+                this.computeWorldMatrix();
             }
             return this._worldMatrixDeterminant;
         }
@@ -835,6 +835,9 @@ module BABYLON {
                 this._poseMatrix = Matrix.Invert(this._worldMatrix);
             }
 
+            // Cache the determinant
+            this._worldMatrixDeterminant = this._worldMatrix.determinant();
+
             return this._worldMatrix;
         }
 

src/Tools/babylon.sceneSerializer.ts

@@ -209,6 +209,11 @@
                 serializationObject.multiMaterials.push(multiMaterial.serialize());
             }
 
+            // Environment texture
+            if (scene.environmentTexture) {
+                serializationObject.environmentTexture = scene.environmentTexture.name;
+            }
+
             // Skeletons
             serializationObject.skeletons = [];
             for (index = 0; index < scene.skeletons.length; index++) {
@@ -219,7 +224,7 @@
             serializationObject.transformNodes = [];
             for (index = 0; index < scene.transformNodes.length; index++) {
                 serializationObject.transformNodes.push(scene.transformNodes[index].serialize());
-            }            
+            }
 
             // Geometries
             serializationObject.geometries = {};

tests/validation/config.json

@@ -176,8 +176,7 @@
     },
     {
       "title": "Normals",
-      "scriptToRun": "/Demos/Normals/index.js",
-      "functionToCall": "createScene",
+      "playgroundId": "#WXKLLJ#2",
       "referenceImage": "normals.png"
     },
     {