const correctness in OpenNI and OpenNI2 getProperty

modules/videoio/src/cap_openni.cpp

@@ -477,11 +477,11 @@ protected:
 
     bool readCamerasParams();
 
-    double getDepthGeneratorProperty(int propIdx);
+    double getDepthGeneratorProperty(int propIdx) const;
     bool setDepthGeneratorProperty(int propIdx, double propVal);
-    double getImageGeneratorProperty(int propIdx);
+    double getImageGeneratorProperty(int propIdx) const;
     bool setImageGeneratorProperty(int propIdx, double propVal);
-    double getCommonProperty(int propIdx);
+    double getCommonProperty(int propIdx) const;
     bool setCommonProperty(int propIdx, double propVal);
 
     // OpenNI context
@@ -820,7 +820,7 @@ bool CvCapture_OpenNI::setProperty( int propIdx, double propValue )
     return isSet;
 }
 
-double CvCapture_OpenNI::getCommonProperty( int propIdx )
+double CvCapture_OpenNI::getCommonProperty( int propIdx ) const
 {
     double propValue = 0;
 
@@ -917,7 +917,7 @@ bool CvCapture_OpenNI::setCommonProperty( int propIdx, double propValue )
     return isSet;
 }
 
-double CvCapture_OpenNI::getDepthGeneratorProperty( int propIdx )
+double CvCapture_OpenNI::getDepthGeneratorProperty( int propIdx ) const
 {
     double propValue = 0;
     if( !depthGenerator.IsValid() )
@@ -953,7 +953,7 @@ double CvCapture_OpenNI::getDepthGeneratorProperty( int propIdx )
         propValue = (double)depthFocalLength_VGA;
         break;
     case CV_CAP_PROP_OPENNI_REGISTRATION :
-        propValue = depthGenerator.GetAlternativeViewPointCap().IsViewPointAs(imageGenerator) ? 1.0 : 0.0;
+        propValue = depthGenerator.GetAlternativeViewPointCap().IsViewPointAs(const_cast<CvCapture_OpenNI *>(this)->imageGenerator) ? 1.0 : 0.0;
         break;
     case CV_CAP_PROP_POS_MSEC :
         propValue = (double)depthGenerator.GetTimestamp();
@@ -1018,7 +1018,7 @@ bool CvCapture_OpenNI::setDepthGeneratorProperty( int propIdx, double propValue
     return isSet;
 }
 
-double CvCapture_OpenNI::getImageGeneratorProperty( int propIdx )
+double CvCapture_OpenNI::getImageGeneratorProperty( int propIdx ) const
 {
     double propValue = 0.;
     if( !imageGenerator.IsValid() )

modules/videoio/src/cap_openni2.cpp

@@ -124,11 +124,11 @@ protected:
 
     bool readCamerasParams();
 
-    double getDepthGeneratorProperty(int propIdx);
+    double getDepthGeneratorProperty(int propIdx) const;
     bool setDepthGeneratorProperty(int propIdx, double propVal);
-    double getImageGeneratorProperty(int propIdx);
+    double getImageGeneratorProperty(int propIdx) const;
     bool setImageGeneratorProperty(int propIdx, double propVal);
-    double getCommonProperty(int propIdx);
+    double getCommonProperty(int propIdx) const;
     bool setCommonProperty(int propIdx, double propVal);
 
     // OpenNI context
@@ -444,7 +444,7 @@ bool CvCapture_OpenNI2::setProperty( int propIdx, double propValue )
     return isSet;
 }
 
-double CvCapture_OpenNI2::getCommonProperty( int propIdx )
+double CvCapture_OpenNI2::getCommonProperty( int propIdx ) const
 {
     double propValue = 0;
 
@@ -508,7 +508,7 @@ bool CvCapture_OpenNI2::setCommonProperty( int propIdx, double propValue )
     return isSet;
 }
 
-double CvCapture_OpenNI2::getDepthGeneratorProperty( int propIdx )
+double CvCapture_OpenNI2::getDepthGeneratorProperty( int propIdx ) const
 {
     double propValue = 0;
     if( !depth.isValid() )
@@ -608,7 +608,7 @@ bool CvCapture_OpenNI2::setDepthGeneratorProperty( int propIdx, double propValue
     return isSet;
 }
 
-double CvCapture_OpenNI2::getImageGeneratorProperty( int propIdx )
+double CvCapture_OpenNI2::getImageGeneratorProperty( int propIdx ) const
 {
     double propValue = 0.;
     if( !color.isValid() )