don't set context shadow props unless we need to

gui/src/controls/checkbox.ts

@@ -82,17 +82,21 @@ module BABYLON.GUI {
                 let actualWidth = this._currentMeasure.width - this._thickness;
                 let actualHeight = this._currentMeasure.height - this._thickness;
 
-                context.shadowColor = this.shadowColor;
-                context.shadowBlur = this.shadowBlur;
-                context.shadowOffsetX = this.shadowOffsetX;
-                context.shadowOffsetY = this.shadowOffsetY;
+                if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                    context.shadowColor = this.shadowColor;
+                    context.shadowBlur = this.shadowBlur;
+                    context.shadowOffsetX = this.shadowOffsetX;
+                    context.shadowOffsetY = this.shadowOffsetY;
+                }
                 
                 context.fillStyle = this._background;
                 context.fillRect(this._currentMeasure.left + this._thickness / 2, this._currentMeasure.top + this._thickness / 2, actualWidth, actualHeight);   
 
-                context.shadowBlur = 0;
-                context.shadowOffsetX = 0;
-                context.shadowOffsetY = 0;
+                if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                    context.shadowBlur = 0;
+                    context.shadowOffsetX = 0;
+                    context.shadowOffsetY = 0;
+                }
 
                 if (this._isChecked) {
                     context.fillStyle = this.color;

gui/src/controls/colorpicker.ts

@@ -287,9 +287,11 @@ module BABYLON.GUI {
 
                 context.drawImage(this._colorWheelCanvas, left, top);
 
-                context.shadowBlur = 0;
-                context.shadowOffsetX = 0;
-                context.shadowOffsetY = 0;
+                if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                    context.shadowBlur = 0;
+                    context.shadowOffsetX = 0;
+                    context.shadowOffsetY = 0;
+                }
 
                 this._drawGradientSquare(this._h, 
                                         this._squareLeft,

gui/src/controls/container.ts

@@ -119,17 +119,21 @@ module BABYLON.GUI {
 
         protected _localDraw(context: CanvasRenderingContext2D): void {
             if (this._background) {
-                context.shadowColor = this.shadowColor;
-                context.shadowBlur = this.shadowBlur;
-                context.shadowOffsetX = this.shadowOffsetX;
-                context.shadowOffsetY = this.shadowOffsetY;
+                if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                    context.shadowColor = this.shadowColor;
+                    context.shadowBlur = this.shadowBlur;
+                    context.shadowOffsetX = this.shadowOffsetX;
+                    context.shadowOffsetY = this.shadowOffsetY;
+                }
                 
                 context.fillStyle = this._background;
                 context.fillRect(this._currentMeasure.left, this._currentMeasure.top, this._currentMeasure.width, this._currentMeasure.height);
                 
-                context.shadowBlur = 0;
-                context.shadowOffsetX = 0;
-                context.shadowOffsetY = 0;        
+                if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                    context.shadowBlur = 0;
+                    context.shadowOffsetX = 0;
+                    context.shadowOffsetY = 0;
+                }
             }
         }
 

gui/src/controls/control.ts

@@ -1075,7 +1075,7 @@ module BABYLON.GUI {
                 panel.addControl(control);
                 header.paddingRight = "5px";
             }
-
+            
             header.shadowBlur = control.shadowBlur;
             header.shadowColor = control.shadowColor;
             header.shadowOffsetX = control.shadowOffsetX;

gui/src/controls/ellipse.ts

@@ -28,10 +28,12 @@ module BABYLON.GUI {
         protected _localDraw(context: CanvasRenderingContext2D): void {
             context.save();
 
-            context.shadowColor = this.shadowColor;
-            context.shadowBlur = this.shadowBlur;
-            context.shadowOffsetX = this.shadowOffsetX;
-            context.shadowOffsetY = this.shadowOffsetY;
+            if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                context.shadowColor = this.shadowColor;
+                context.shadowBlur = this.shadowBlur;
+                context.shadowOffsetX = this.shadowOffsetX;
+                context.shadowOffsetY = this.shadowOffsetY;
+            }
 
             Control.drawEllipse(this._currentMeasure.left + this._currentMeasure.width / 2, this._currentMeasure.top + this._currentMeasure.height / 2, 
                             this._currentMeasure.width / 2 - this._thickness / 2, this._currentMeasure.height / 2 - this._thickness / 2, context);
@@ -42,9 +44,11 @@ module BABYLON.GUI {
                 context.fill();
             }
 
-            context.shadowBlur = 0;
-            context.shadowOffsetX = 0;
-            context.shadowOffsetY = 0;
+            if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                context.shadowBlur = 0;
+                context.shadowOffsetX = 0;
+                context.shadowOffsetY = 0;
+            }
 
             if (this._thickness) {
                 if (this.color) {

gui/src/controls/image.ts

@@ -198,10 +198,12 @@ module BABYLON.GUI {
         public _draw(parentMeasure: Measure, context: CanvasRenderingContext2D): void {
             context.save();
 
-            context.shadowColor = this.shadowColor;
-            context.shadowBlur = this.shadowBlur;
-            context.shadowOffsetX = this.shadowOffsetX;
-            context.shadowOffsetY = this.shadowOffsetY;
+            if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                context.shadowColor = this.shadowColor;
+                context.shadowBlur = this.shadowBlur;
+                context.shadowOffsetX = this.shadowOffsetX;
+                context.shadowOffsetY = this.shadowOffsetY;
+            }
 
             let x, y, width, height;
             if (this.cellId == -1) {

gui/src/controls/line.ts

@@ -146,10 +146,12 @@ module BABYLON.GUI {
         public _draw(parentMeasure: Measure, context: CanvasRenderingContext2D): void {
             context.save();
 
-            context.shadowColor = this.shadowColor;
-            context.shadowBlur = this.shadowBlur;
-            context.shadowOffsetX = this.shadowOffsetX;
-            context.shadowOffsetY = this.shadowOffsetY;
+            if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                context.shadowColor = this.shadowColor;
+                context.shadowBlur = this.shadowBlur;
+                context.shadowOffsetX = this.shadowOffsetX;
+                context.shadowOffsetY = this.shadowOffsetY;
+            }
 
             this._applyStates(context);
             if (this._processMeasures(parentMeasure, context)) {

gui/src/controls/radioButton.ts

@@ -102,10 +102,12 @@ module BABYLON.GUI {
                 let actualWidth = this._currentMeasure.width - this._thickness;
                 let actualHeight = this._currentMeasure.height - this._thickness;
 
-                context.shadowColor = this.shadowColor;
-                context.shadowBlur = this.shadowBlur;
-                context.shadowOffsetX = this.shadowOffsetX;
-                context.shadowOffsetY = this.shadowOffsetY;
+                if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                    context.shadowColor = this.shadowColor;
+                    context.shadowBlur = this.shadowBlur;
+                    context.shadowOffsetX = this.shadowOffsetX;
+                    context.shadowOffsetY = this.shadowOffsetY;
+                }
                 
                 // Outer
                 Control.drawEllipse(this._currentMeasure.left + this._currentMeasure.width / 2, this._currentMeasure.top + this._currentMeasure.height / 2, 
@@ -114,9 +116,11 @@ module BABYLON.GUI {
                 context.fillStyle = this._background;
                 context.fill();
 
-                context.shadowBlur = 0;
-                context.shadowOffsetX = 0;
-                context.shadowOffsetY = 0;
+                if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                    context.shadowBlur = 0;
+                    context.shadowOffsetX = 0;
+                    context.shadowOffsetY = 0;
+                }
 
                 context.strokeStyle = this.color;
                 context.lineWidth = this._thickness;

gui/src/controls/rectangle.ts

@@ -46,10 +46,12 @@ module BABYLON.GUI {
         protected _localDraw(context: CanvasRenderingContext2D): void {
             context.save();
             
-            context.shadowColor = this.shadowColor;
-            context.shadowBlur = this.shadowBlur;
-            context.shadowOffsetX = this.shadowOffsetX;
-            context.shadowOffsetY = this.shadowOffsetY;
+            if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                context.shadowColor = this.shadowColor;
+                context.shadowBlur = this.shadowBlur;
+                context.shadowOffsetX = this.shadowOffsetX;
+                context.shadowOffsetY = this.shadowOffsetY;
+            }
 
             if (this._background) {
                 context.fillStyle = this._background;
@@ -64,9 +66,11 @@ module BABYLON.GUI {
 
             if (this._thickness) {
 
-                context.shadowBlur = 0;
-                context.shadowOffsetX = 0;
-                context.shadowOffsetY = 0;
+                if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                    context.shadowBlur = 0;
+                    context.shadowOffsetX = 0;
+                    context.shadowOffsetY = 0;
+                }
 
                 if (this.color) {
                     context.strokeStyle = this.color;

gui/src/controls/textBlock.ts

@@ -106,10 +106,12 @@ module BABYLON.GUI {
                     break;
             }
 
-            context.shadowColor = this.shadowColor;
-            context.shadowBlur = this.shadowBlur;
-            context.shadowOffsetX = this.shadowOffsetX;
-            context.shadowOffsetY = this.shadowOffsetY;
+            if(this.shadowBlur || this.shadowOffsetX || this.shadowOffsetY){
+                context.shadowColor = this.shadowColor;
+                context.shadowBlur = this.shadowBlur;
+                context.shadowOffsetX = this.shadowOffsetX;
+                context.shadowOffsetY = this.shadowOffsetY;
+            }
 
             context.fillText(text, this._currentMeasure.left + x, y);
         }