boudning box mesh sizing and option for constant screen size

src/Gizmos/babylon.boundingBoxGizmo.ts

@@ -15,6 +15,19 @@ module BABYLON {
         private _tmpVector = new Vector3(0,0,0);
 
         /**
+         * The size of the rotation spheres attached to the bounding box (Default: 0.1)
+         */
+        public rotationSphereSize = 0.1;
+        /**
+         * The size of the scale boxes attached to the bounding box (Default: 0.1)
+         */
+        public scaleBoxSize = 0.1;
+        /**
+         * If set, the rotation spheres and scale boxes will increase in size based on the distance away from the camera to have a consistent screen size (Default: false)
+         */
+        public fixedDragMeshScreenSize = false;
+
+        /**
          * Fired when a rotation sphere or scale box is dragged
          */
         public dragStartObservable = new Observable<{}>();
@@ -74,7 +87,7 @@ module BABYLON {
             this._rotateSpheresParent = new BABYLON.AbstractMesh("", gizmoLayer.utilityLayerScene);
             this._rotateSpheresParent.rotationQuaternion = new Quaternion();
             for(let i=0;i<12;i++){
-                let sphere = BABYLON.MeshBuilder.CreateSphere("", {diameter: 0.1}, gizmoLayer.utilityLayerScene);
+                let sphere = BABYLON.MeshBuilder.CreateSphere("", {diameter: 1}, gizmoLayer.utilityLayerScene);
                 sphere.rotationQuaternion = new Quaternion();
                 sphere.material = coloredMaterial;
 
@@ -141,7 +154,7 @@ module BABYLON {
             for(var i=0;i<2;i++){
                 for(var j=0;j<2;j++){
                     for(var k=0;k<2;k++){
-                        let box = BABYLON.MeshBuilder.CreateBox("", {size: 0.1}, gizmoLayer.utilityLayerScene);
+                        let box = BABYLON.MeshBuilder.CreateBox("", {size: 1}, gizmoLayer.utilityLayerScene);
                         box.material = coloredMaterial;
 
                         // Dragging logic
@@ -218,7 +231,7 @@ module BABYLON {
             })
         }
 
-        private _updateBoundingBox(){   
+        private _updateBoundingBox(){
             if(this.attachedMesh){
                 // Update bounding dimensions/positions
                 var boundingInfo = this.attachedMesh.getBoundingInfo().boundingBox;
@@ -248,6 +261,13 @@ module BABYLON {
                             rotateSpheres[index].position.addInPlace(new BABYLON.Vector3(-this._boundingDimensions.x/2,-this._boundingDimensions.y/2,-this._boundingDimensions.z/2));
                             rotateSpheres[index].lookAt(Vector3.Cross(Vector3.Forward(), rotateSpheres[index].position.normalizeToNew()).normalizeToNew().add(rotateSpheres[index].position));
                         }
+                        if(this.fixedDragMeshScreenSize){
+                            rotateSpheres[index].absolutePosition.subtractToRef(this.gizmoLayer.utilityLayerScene.activeCamera!.position, this._tmpVector);
+                            var distanceFromCamera = this.rotationSphereSize*this._tmpVector.length()/9;
+                            rotateSpheres[index].scaling.set(distanceFromCamera, distanceFromCamera, distanceFromCamera);
+                        }else{
+                            rotateSpheres[index].scaling.set(this.rotationSphereSize, this.rotationSphereSize, this.rotationSphereSize);
+                        }
                     }
                 }
             }
@@ -261,6 +281,13 @@ module BABYLON {
                         if(scaleBoxes[index]){
                             scaleBoxes[index].position.set(this._boundingDimensions.x*i,this._boundingDimensions.y*j,this._boundingDimensions.z*k);
                             scaleBoxes[index].position.addInPlace(new BABYLON.Vector3(-this._boundingDimensions.x/2,-this._boundingDimensions.y/2,-this._boundingDimensions.z/2));
+                            if(this.fixedDragMeshScreenSize){
+                                scaleBoxes[index].absolutePosition.subtractToRef(this.gizmoLayer.utilityLayerScene.activeCamera!.position, this._tmpVector);
+                                var distanceFromCamera = this.scaleBoxSize*this._tmpVector.length()/9;
+                                scaleBoxes[index].scaling.set(distanceFromCamera, distanceFromCamera, distanceFromCamera);
+                            }else{
+                                scaleBoxes[index].scaling.set(this.scaleBoxSize, this.scaleBoxSize, this.scaleBoxSize);
+                            }
                         }
                     }
                 }