diff --git a/Sources/Rendering/OpenGL/ImageMapper/index.js b/Sources/Rendering/OpenGL/ImageMapper/index.js
index ff358985dd3..95bb345bf8b 100644
--- a/Sources/Rendering/OpenGL/ImageMapper/index.js
+++ b/Sources/Rendering/OpenGL/ImageMapper/index.js
@@ -89,7 +89,7 @@ function vtkOpenGLImageMapper(publicAPI, model) {
         !oldOglRenderWindow.isDeleted() &&
         oldOglRenderWindow !== model._openGLRenderWindow
       ) {
-        // We unregister ourself when the render window changes
+        // Unregister the mapper when the render window changes
         unregisterGraphicsResources(oldOglRenderWindow);
       }
       model.context = model._openGLRenderWindow.getContext();
@@ -1016,14 +1016,16 @@ function vtkOpenGLImageMapper(publicAPI, model) {
           model.colorTexture,
           cfunToString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._colorTransferFunc,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          colorTransferFunc,
-          publicAPI
-        );
+        if (colorTransferFunc !== model._colorTransferFunc) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            colorTransferFunc,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._colorTransferFunc,
+            publicAPI
+          );
+        }
         model._colorTransferFunc = colorTransferFunc;
       }
     } else {
@@ -1108,14 +1110,16 @@ function vtkOpenGLImageMapper(publicAPI, model) {
           model.pwfTexture,
           pwfunToString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._pwFunc,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          pwFunc,
-          publicAPI
-        );
+        if (pwFunc !== model._pwFunc) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            pwFunc,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._pwFunc,
+            publicAPI
+          );
+        }
         model._pwFunc = pwFunc;
       }
     } else {
@@ -1406,14 +1410,16 @@ function vtkOpenGLImageMapper(publicAPI, model) {
           model.labelOutlineThicknessTexture,
           toString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._labelOutlineThicknessArray,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          labelOutlineThicknessArray,
-          publicAPI
-        );
+        if (labelOutlineThicknessArray !== model._labelOutlineThicknessArray) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            labelOutlineThicknessArray,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._labelOutlineThicknessArray,
+            publicAPI
+          );
+        }
         model._labelOutlineThicknessArray = labelOutlineThicknessArray;
       }
     } else {
diff --git a/Sources/Rendering/OpenGL/ImageResliceMapper/index.js b/Sources/Rendering/OpenGL/ImageResliceMapper/index.js
index a13a74a5a4d..011c3c8c5ce 100644
--- a/Sources/Rendering/OpenGL/ImageResliceMapper/index.js
+++ b/Sources/Rendering/OpenGL/ImageResliceMapper/index.js
@@ -85,7 +85,7 @@ function vtkOpenGLImageResliceMapper(publicAPI, model) {
         !oldOglRenderWindow.isDeleted() &&
         oldOglRenderWindow !== model._openGLRenderWindow
       ) {
-        // We unregister ourself when the render window changes
+        // Unregister the mapper when the render window changes
         unregisterGraphicsResources(oldOglRenderWindow);
       }
       model.context = model._openGLRenderWindow.getContext();
@@ -252,14 +252,16 @@ function vtkOpenGLImageResliceMapper(publicAPI, model) {
           model.openGLTexture,
           toString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._scalars,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          scalars,
-          publicAPI
-        );
+        if (scalars !== model._scalars) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            scalars,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._scalars,
+            publicAPI
+          );
+        }
         model._scalars = scalars;
       }
     } else {
@@ -330,14 +332,16 @@ function vtkOpenGLImageResliceMapper(publicAPI, model) {
           model.colorTexture,
           toString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._colorTransferFunc,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          colorTransferFunc,
-          publicAPI
-        );
+        if (colorTransferFunc !== model._colorTransferFunc) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            colorTransferFunc,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._colorTransferFunc,
+            publicAPI
+          );
+        }
         model._colorTransferFunc = colorTransferFunc;
       }
     } else {
@@ -411,14 +415,16 @@ function vtkOpenGLImageResliceMapper(publicAPI, model) {
           model.pwfTexture,
           toString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._pwFunc,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          pwFunc,
-          publicAPI
-        );
+        if (pwFunc !== model._pwFunc) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            pwFunc,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._pwFunc,
+            publicAPI
+          );
+        }
         model._pwFunc = pwFunc;
       }
     } else {
diff --git a/Sources/Rendering/OpenGL/VolumeMapper/index.js b/Sources/Rendering/OpenGL/VolumeMapper/index.js
index cb71f081b6f..f252a3266cd 100644
--- a/Sources/Rendering/OpenGL/VolumeMapper/index.js
+++ b/Sources/Rendering/OpenGL/VolumeMapper/index.js
@@ -164,7 +164,7 @@ function vtkOpenGLVolumeMapper(publicAPI, model) {
         !oldOglRenderWindow.isDeleted() &&
         oldOglRenderWindow !== model._openGLRenderWindow
       ) {
-        // We unregister ourself when the render window changes
+        // Unregister the mapper when the render window changes
         unregisterGraphicsResources(oldOglRenderWindow);
       }
       model.context = model._openGLRenderWindow.getContext();
@@ -1612,14 +1612,16 @@ function vtkOpenGLVolumeMapper(publicAPI, model) {
           model.opacityTexture,
           toString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._scalarOpacityFunc,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          scalarOpacityFunc,
-          publicAPI
-        );
+        if (scalarOpacityFunc !== model._scalarOpacityFunc) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            scalarOpacityFunc,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._scalarOpacityFunc,
+            publicAPI
+          );
+        }
         model._scalarOpacityFunc = scalarOpacityFunc;
       }
     } else {
@@ -1671,14 +1673,16 @@ function vtkOpenGLVolumeMapper(publicAPI, model) {
           model.colorTexture,
           toString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._colorTransferFunc,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          colorTransferFunc,
-          publicAPI
-        );
+        if (colorTransferFunc !== model._colorTransferFunc) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            colorTransferFunc,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._colorTransferFunc,
+            publicAPI
+          );
+        }
         model._colorTransferFunc = colorTransferFunc;
       }
     } else {
@@ -1714,14 +1718,16 @@ function vtkOpenGLVolumeMapper(publicAPI, model) {
           model.scalarTexture,
           toString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._scalars,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          scalars,
-          publicAPI
-        );
+        if (scalars !== model._scalars) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            scalars,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._scalars,
+            publicAPI
+          );
+        }
         model._scalars = scalars;
       }
     } else {
@@ -1848,14 +1854,16 @@ function vtkOpenGLVolumeMapper(publicAPI, model) {
           model.labelOutlineThicknessTexture,
           toString
         );
-        model._openGLRenderWindow.unregisterGraphicsResourceUser(
-          model._labelOutlineThicknessArray,
-          publicAPI
-        );
-        model._openGLRenderWindow.registerGraphicsResourceUser(
-          labelOutlineThicknessArray,
-          publicAPI
-        );
+        if (labelOutlineThicknessArray !== model._labelOutlineThicknessArray) {
+          model._openGLRenderWindow.registerGraphicsResourceUser(
+            labelOutlineThicknessArray,
+            publicAPI
+          );
+          model._openGLRenderWindow.unregisterGraphicsResourceUser(
+            model._labelOutlineThicknessArray,
+            publicAPI
+          );
+        }
         model._labelOutlineThicknessArray = labelOutlineThicknessArray;
       }
     } else {