Gui: reset model transformation scaling in SoAutoZoomTranslation

src/Gui/Inventor/SoAutoZoomTranslation.cpp

@@ -100,8 +100,15 @@ void SoAutoZoomTranslation::GLRender(SoGLRenderAction * action)
 void SoAutoZoomTranslation::doAction(SoAction * action)
 {
     float sf = this->getScaleFactor(action);
-    SoModelMatrixElement::scaleBy(action->getState(), this,
-                                SbVec3f(sf,sf,sf));
+    auto state = action->getState();
+    SbRotation r,so;
+    SbVec3f s,t;
+    SbMatrix matrix = SoModelMatrixElement::get(action->getState());
+    matrix.getTransform(t,r,s,so);
+    matrix.multVecMatrix(SbVec3f(0,0,0),t);
+    // reset current model scale factor
+    matrix.setTransform(t,r,SbVec3f(sf,sf,sf));
+    SoModelMatrixElement::set(state,this,matrix);
 }
 
 // set the auto scale factor.
@@ -119,14 +126,15 @@ void SoAutoZoomTranslation::getMatrix(SoGetMatrixAction * action)
 {
     float sf = this->getScaleFactor(action);
 
-    SbVec3f scalevec = SbVec3f(sf,sf,sf);
-    SbMatrix m;
+    SbMatrix &m = action->getMatrix();
 
-    m.setScale(scalevec);
-    action->getMatrix().multLeft(m);
+    SbRotation r,so;
+    SbVec3f s,t;
+    m.getTransform(t,r,s,so);
+    m.multVecMatrix(SbVec3f(0,0,0),t);
+    m.setTransform(t,r,SbVec3f(sf,sf,sf));
 
-    m.setScale(SbVec3f(1.0f / scalevec[0], 1.0f / scalevec[1], 1.0f / scalevec[2]));
-    action->getInverse().multRight(m);
+    action->getInverse() = m.inverse();
 }
 
 void SoAutoZoomTranslation::callback(SoCallbackAction * action)