From 445eb19cf8eb2f043e32e650df12fe9b95cd07fe Mon Sep 17 00:00:00 2001
From: alemuntoni <muntoni.alessandro@gmail.com>
Date: Thu, 17 Sep 2020 14:08:51 +0200
Subject: [PATCH] applyFilter const correctness

---
 src/common/interfaces.h                                       | 2 +-
 src/meshlabplugins/filter_ao/filter_ao.cpp                    | 2 +-
 src/meshlabplugins/filter_ao/filter_ao.h                      | 2 +-
 src/meshlabplugins/filter_camera/filter_camera.cpp            | 2 +-
 src/meshlabplugins/filter_camera/filter_camera.h              | 2 +-
 src/meshlabplugins/filter_clean/cleanfilter.cpp               | 2 +-
 src/meshlabplugins/filter_clean/cleanfilter.h                 | 2 +-
 .../filter_color_projection/filter_color_projection.cpp       | 2 +-
 .../filter_color_projection/filter_color_projection.h         | 2 +-
 src/meshlabplugins/filter_colorproc/filter_colorproc.cpp      | 2 +-
 src/meshlabplugins/filter_colorproc/filter_colorproc.h        | 2 +-
 src/meshlabplugins/filter_create/filter_create.cpp            | 2 +-
 src/meshlabplugins/filter_create/filter_create.h              | 2 +-
 src/meshlabplugins/filter_createiso/filter_createiso.cpp      | 2 +-
 src/meshlabplugins/filter_createiso/filter_createiso.h        | 2 +-
 src/meshlabplugins/filter_csg/filter_csg.cpp                  | 2 +-
 src/meshlabplugins/filter_csg/filter_csg.h                    | 4 ++--
 src/meshlabplugins/filter_dirt/filter_dirt.cpp                | 2 +-
 src/meshlabplugins/filter_dirt/filter_dirt.h                  | 4 ++--
 src/meshlabplugins/filter_fractal/filter_fractal.cpp          | 2 +-
 src/meshlabplugins/filter_fractal/filter_fractal.h            | 2 +-
 src/meshlabplugins/filter_func/filter_func.cpp                | 2 +-
 src/meshlabplugins/filter_func/filter_func.h                  | 2 +-
 src/meshlabplugins/filter_geodesic/filter_geodesic.cpp        | 2 +-
 src/meshlabplugins/filter_geodesic/filter_geodesic.h          | 2 +-
 .../filter_globalregistration/globalregistration.cpp          | 2 +-
 .../filter_globalregistration/globalregistration.h            | 2 +-
 .../filter_img_patch_param/filter_img_patch_param.cpp         | 2 +-
 .../filter_img_patch_param/filter_img_patch_param.h           | 2 +-
 .../filter_isoparametrization/filter_isoparametrization.cpp   | 2 +-
 .../filter_isoparametrization/filter_isoparametrization.h     | 2 +-
 src/meshlabplugins/filter_layer/filter_layer.cpp              | 2 +-
 src/meshlabplugins/filter_layer/filter_layer.h                | 2 +-
 src/meshlabplugins/filter_measure/filter_measure.cpp          | 2 +-
 src/meshlabplugins/filter_measure/filter_measure.h            | 2 +-
 src/meshlabplugins/filter_meshing/meshfilter.cpp              | 2 +-
 src/meshlabplugins/filter_meshing/meshfilter.h                | 2 +-
 src/meshlabplugins/filter_mls/mlsplugin.cpp                   | 2 +-
 src/meshlabplugins/filter_mls/mlsplugin.h                     | 2 +-
 .../filter_mutualglobal/filter_mutualglobal.cpp               | 2 +-
 src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.h  | 2 +-
 src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.cpp    | 2 +-
 src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.h      | 2 +-
 src/meshlabplugins/filter_plymc/filter_plymc.cpp              | 2 +-
 src/meshlabplugins/filter_plymc/filter_plymc.h                | 2 +-
 src/meshlabplugins/filter_qhull/filter_qhull.cpp              | 2 +-
 src/meshlabplugins/filter_qhull/filter_qhull.h                | 2 +-
 src/meshlabplugins/filter_quality/filterqualitymapper.cpp     | 2 +-
 src/meshlabplugins/filter_quality/filterqualitymapper.h       | 2 +-
 src/meshlabplugins/filter_sample/filter_sample.cpp            | 2 +-
 src/meshlabplugins/filter_sample/filter_sample.h              | 2 +-
 src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.cpp    | 2 +-
 src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.h      | 2 +-
 src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.cpp    | 2 +-
 src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.h      | 2 +-
 src/meshlabplugins/filter_sampling/filter_sampling.cpp        | 2 +-
 src/meshlabplugins/filter_sampling/filter_sampling.h          | 2 +-
 .../filter_screened_poisson/filter_screened_poisson.cpp       | 2 +-
 .../filter_screened_poisson/filter_screened_poisson.h         | 3 +--
 src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.cpp            | 2 +-
 src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.h              | 2 +-
 src/meshlabplugins/filter_sdfgpu/filterinterface.h            | 2 +-
 src/meshlabplugins/filter_select/meshselect.cpp               | 2 +-
 src/meshlabplugins/filter_select/meshselect.h                 | 2 +-
 src/meshlabplugins/filter_sketchfab/filter_sketchfab.cpp      | 2 +-
 src/meshlabplugins/filter_sketchfab/filter_sketchfab.h        | 2 +-
 src/meshlabplugins/filter_ssynth/filter_ssynth.cpp            | 2 +-
 src/meshlabplugins/filter_ssynth/filter_ssynth.h              | 2 +-
 src/meshlabplugins/filter_texture/filter_texture.cpp          | 2 +-
 src/meshlabplugins/filter_texture/filter_texture.h            | 2 +-
 src/meshlabplugins/filter_trioptimize/filter_trioptimize.cpp  | 4 ++--
 src/meshlabplugins/filter_trioptimize/filter_trioptimize.h    | 4 ++--
 src/meshlabplugins/filter_unsharp/filter_unsharp.cpp          | 2 +-
 src/meshlabplugins/filter_unsharp/filter_unsharp.h            | 2 +-
 src/meshlabplugins/filter_voronoi/filter_voronoi.cpp          | 4 ++--
 src/meshlabplugins/filter_voronoi/filter_voronoi.h            | 4 ++--
 76 files changed, 82 insertions(+), 83 deletions(-)

diff --git a/src/common/interfaces.h b/src/common/interfaces.h
index ba18a5178..c843510ca 100644
--- a/src/common/interfaces.h
+++ b/src/common/interfaces.h
@@ -381,7 +381,7 @@ public:
 	* \sa errorMsg
 	* \sa initParameterSet
 	*/
-	virtual bool applyFilter(QAction *   filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb) = 0;
+	virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb) = 0;
 
 	/** \brief tests if a filter is applicable to a mesh.
 	This function is a handy wrapper used by the framework for the \a getPreConditions callback;
diff --git a/src/meshlabplugins/filter_ao/filter_ao.cpp b/src/meshlabplugins/filter_ao/filter_ao.cpp
index 1253b34b5..c359a21d4 100644
--- a/src/meshlabplugins/filter_ao/filter_ao.cpp
+++ b/src/meshlabplugins/filter_ao/filter_ao.cpp
@@ -130,7 +130,7 @@ void AmbientOcclusionPlugin::initParameterSet(QAction *action, MeshModel & /*m*/
 		default: break; // do not add any parameter for the other filters
     }
 }
-bool AmbientOcclusionPlugin::applyFilter(QAction * /*filter*/, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool AmbientOcclusionPlugin::applyFilter(const QAction * /*filter*/, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
     MeshModel &m=*(md.mm());
 
diff --git a/src/meshlabplugins/filter_ao/filter_ao.h b/src/meshlabplugins/filter_ao/filter_ao.h
index 808d5f447..e3e7bbae2 100644
--- a/src/meshlabplugins/filter_ao/filter_ao.h
+++ b/src/meshlabplugins/filter_ao/filter_ao.h
@@ -76,7 +76,7 @@ public:
     FilterClass getClass(const QAction* filter) const;
 
     void initParameterSet(QAction *,MeshModel &/*m*/,RichParameterList & /*parent*/);
-    bool applyFilter(QAction *filter,MeshDocument &md,const RichParameterList & /*parent*/,vcg::CallBackPos * cb) ;
+    bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     void initTextures(void);
     void initGL(vcg::CallBackPos *cb,unsigned int numVertices);
     bool processGL(MeshModel &m, std::vector<vcg::Point3f> &posVect);
diff --git a/src/meshlabplugins/filter_camera/filter_camera.cpp b/src/meshlabplugins/filter_camera/filter_camera.cpp
index f17c5250f..073999287 100644
--- a/src/meshlabplugins/filter_camera/filter_camera.cpp
+++ b/src/meshlabplugins/filter_camera/filter_camera.cpp
@@ -184,7 +184,7 @@ void FilterCameraPlugin::initParameterSet(QAction *action, MeshDocument &/*m*/,
 }
 
 // Core Function doing the actual mesh processing.
-bool FilterCameraPlugin::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * /*cb*/)
+bool FilterCameraPlugin::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * /*cb*/)
 {
     MeshModel* mesh = md.mm();
     CMeshO* cm = NULL;
diff --git a/src/meshlabplugins/filter_camera/filter_camera.h b/src/meshlabplugins/filter_camera/filter_camera.h
index 1f5b4fa3c..d6e91d836 100644
--- a/src/meshlabplugins/filter_camera/filter_camera.h
+++ b/src/meshlabplugins/filter_camera/filter_camera.h
@@ -52,7 +52,7 @@ public:
 	virtual QString filterInfo(FilterIDType filter) const;
 	virtual FilterClass getClass(const QAction*) const;
 	virtual void initParameterSet(QAction *,MeshDocument &/*m*/, RichParameterList & /*parent*/);
-	virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     FILTER_ARITY filterArity(QAction* act) const;
 };
 
diff --git a/src/meshlabplugins/filter_clean/cleanfilter.cpp b/src/meshlabplugins/filter_clean/cleanfilter.cpp
index 787021411..f15c557d4 100644
--- a/src/meshlabplugins/filter_clean/cleanfilter.cpp
+++ b/src/meshlabplugins/filter_clean/cleanfilter.cpp
@@ -269,7 +269,7 @@ void CleanFilter::initParameterSet(QAction *action,MeshDocument &md, RichParamet
   }
 }
 
-bool CleanFilter::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * cb)
+bool CleanFilter::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * cb)
 {
  MeshModel &m=*(md.mm());
  switch(ID(filter))
diff --git a/src/meshlabplugins/filter_clean/cleanfilter.h b/src/meshlabplugins/filter_clean/cleanfilter.h
index fff19b728..f58511617 100644
--- a/src/meshlabplugins/filter_clean/cleanfilter.h
+++ b/src/meshlabplugins/filter_clean/cleanfilter.h
@@ -72,7 +72,7 @@ public:
     int postCondition(const QAction* ) const;
     int getPreConditions(QAction *) const {    return MeshModel::MM_NONE; } 
     virtual void initParameterSet(QAction *,MeshDocument &/*m*/, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
 };
 
diff --git a/src/meshlabplugins/filter_color_projection/filter_color_projection.cpp b/src/meshlabplugins/filter_color_projection/filter_color_projection.cpp
index d0a48afde..fa4296586 100644
--- a/src/meshlabplugins/filter_color_projection/filter_color_projection.cpp
+++ b/src/meshlabplugins/filter_color_projection/filter_color_projection.cpp
@@ -218,7 +218,7 @@ void FilterColorProjectionPlugin::initParameterSet(QAction *action, MeshDocument
 }
 
 // Core Function doing the actual mesh processing.
-bool FilterColorProjectionPlugin::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterColorProjectionPlugin::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
     //CMeshO::FaceIterator fi;
     CMeshO::VertexIterator vi;
diff --git a/src/meshlabplugins/filter_color_projection/filter_color_projection.h b/src/meshlabplugins/filter_color_projection/filter_color_projection.h
index ce45a658b..3b9e310eb 100644
--- a/src/meshlabplugins/filter_color_projection/filter_color_projection.h
+++ b/src/meshlabplugins/filter_color_projection/filter_color_projection.h
@@ -46,7 +46,7 @@ public:
     virtual FilterClass getClass(const QAction*) const;
     virtual void initParameterSet(QAction *,MeshDocument &/*m*/, RichParameterList & /*parent*/);
     virtual int getRequirements(QAction *);
-    virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
 
     FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
 
diff --git a/src/meshlabplugins/filter_colorproc/filter_colorproc.cpp b/src/meshlabplugins/filter_colorproc/filter_colorproc.cpp
index cbcce9742..c1d004c49 100644
--- a/src/meshlabplugins/filter_colorproc/filter_colorproc.cpp
+++ b/src/meshlabplugins/filter_colorproc/filter_colorproc.cpp
@@ -368,7 +368,7 @@ void FilterColorProc::initParameterSet(QAction *a, MeshDocument& md, RichParamet
 	}
 }
 
-bool FilterColorProc::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList &par, vcg::CallBackPos *cb)
+bool FilterColorProc::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList &par, vcg::CallBackPos *cb)
 {
 	MeshModel *m = md.mm();  //get current mesh from document
 
diff --git a/src/meshlabplugins/filter_colorproc/filter_colorproc.h b/src/meshlabplugins/filter_colorproc/filter_colorproc.h
index 779be78f6..5f55f9bbb 100644
--- a/src/meshlabplugins/filter_colorproc/filter_colorproc.h
+++ b/src/meshlabplugins/filter_colorproc/filter_colorproc.h
@@ -75,7 +75,7 @@ public:
     virtual int getRequirements(QAction *);
 
     virtual void initParameterSet(QAction *,MeshDocument&, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction *filter, MeshDocument&, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
+    virtual bool applyFilter(const QAction* filter, MeshDocument&, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
     int postCondition(const QAction* filter) const;
     int getPreConditions(QAction *) const;
     FILTER_ARITY filterArity(QAction *act) const;
diff --git a/src/meshlabplugins/filter_create/filter_create.cpp b/src/meshlabplugins/filter_create/filter_create.cpp
index af6c6b575..f78584406 100644
--- a/src/meshlabplugins/filter_create/filter_create.cpp
+++ b/src/meshlabplugins/filter_create/filter_create.cpp
@@ -167,7 +167,7 @@ void FilterCreate::initParameterSet(QAction *action, MeshModel & /*m*/, RichPara
 }
 
 // The Real Core Function doing the actual mesh processing.
-bool FilterCreate::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, CallBackPos * /*cb*/)
+bool FilterCreate::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, CallBackPos * /*cb*/)
 {
 	MeshModel *currM = md.mm();
 	MeshModel *m = nullptr;
diff --git a/src/meshlabplugins/filter_create/filter_create.h b/src/meshlabplugins/filter_create/filter_create.h
index 3c3d8d8c4..4e0d78f76 100644
--- a/src/meshlabplugins/filter_create/filter_create.h
+++ b/src/meshlabplugins/filter_create/filter_create.h
@@ -54,7 +54,7 @@ class FilterCreate : public QObject, public MeshFilterInterface
   QString filterInfo(FilterIDType filter) const;
   FilterClass getClass(const QAction*) const;
   void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
-  bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+  bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
   QString filterScriptFunctionName(FilterIDType filterID);
   FILTER_ARITY filterArity(QAction *) const {return NONE;}
 };
diff --git a/src/meshlabplugins/filter_createiso/filter_createiso.cpp b/src/meshlabplugins/filter_createiso/filter_createiso.cpp
index 4c965e393..4c58bcd31 100644
--- a/src/meshlabplugins/filter_createiso/filter_createiso.cpp
+++ b/src/meshlabplugins/filter_createiso/filter_createiso.cpp
@@ -98,7 +98,7 @@ QString FilterCreateIso::pluginName() const
   return 0;
 }
 
- bool FilterCreateIso::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * cb)
+ bool FilterCreateIso::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * cb)
  {
    md.addNewMesh("",this->filterName(ID(filter)));
    MeshModel &m=*(md.mm());
diff --git a/src/meshlabplugins/filter_createiso/filter_createiso.h b/src/meshlabplugins/filter_createiso/filter_createiso.h
index eb82900d7..32d0cd71f 100644
--- a/src/meshlabplugins/filter_createiso/filter_createiso.h
+++ b/src/meshlabplugins/filter_createiso/filter_createiso.h
@@ -63,7 +63,7 @@ public:
     virtual int getRequirements(QAction *);
     virtual void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
 
-    virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     FILTER_ARITY filterArity(QAction*) const {return NONE;}
 
 };
diff --git a/src/meshlabplugins/filter_csg/filter_csg.cpp b/src/meshlabplugins/filter_csg/filter_csg.cpp
index 974c676e9..2654800c2 100644
--- a/src/meshlabplugins/filter_csg/filter_csg.cpp
+++ b/src/meshlabplugins/filter_csg/filter_csg.cpp
@@ -116,7 +116,7 @@ void FilterCSG::initParameterSet(QAction *action, MeshDocument & md, RichParamet
     }
 }
 
-bool FilterCSG::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterCSG::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
     switch(ID(filter)) {
     case FP_CSG:
diff --git a/src/meshlabplugins/filter_csg/filter_csg.h b/src/meshlabplugins/filter_csg/filter_csg.h
index 29139655f..a926e3cff 100644
--- a/src/meshlabplugins/filter_csg/filter_csg.h
+++ b/src/meshlabplugins/filter_csg/filter_csg.h
@@ -62,8 +62,8 @@ public:
     virtual void initParameterSet(QAction *, MeshDocument &, RichParameterList &);
     virtual void initParameterSet(QAction *, MeshModel &, RichParameterList &) { assert(0); }
 
-    virtual bool applyFilter(QAction *, MeshDocument &, const RichParameterList &, vcg::CallBackPos *);
-    virtual bool applyFilter(QAction *, MeshModel &, const RichParameterList &, vcg::CallBackPos *) { assert(0); return false; }
+    virtual bool applyFilter(const QAction*, MeshDocument &, const RichParameterList &, vcg::CallBackPos *);
+    virtual bool applyFilter(const QAction *, MeshModel &, const RichParameterList &, vcg::CallBackPos *) { assert(0); return false; }
 
     virtual FilterClass getClass(const QAction *) const { return MeshFilterInterface::FilterClass( MeshFilterInterface::Layer + MeshFilterInterface::Remeshing ); }
     FILTER_ARITY filterArity(QAction*) const {return FIXED;}
diff --git a/src/meshlabplugins/filter_dirt/filter_dirt.cpp b/src/meshlabplugins/filter_dirt/filter_dirt.cpp
index 6b32021e2..f76d797d8 100644
--- a/src/meshlabplugins/filter_dirt/filter_dirt.cpp
+++ b/src/meshlabplugins/filter_dirt/filter_dirt.cpp
@@ -133,7 +133,7 @@ int FilterDirt::getRequirements(QAction * /*action*/)
     return MeshModel::MM_FACEFACETOPO | MeshModel::MM_VERTCOLOR |MeshModel::MM_FACECOLOR;
 }
 
-bool FilterDirt::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList &par, vcg::CallBackPos *cb){
+bool FilterDirt::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList &par, vcg::CallBackPos *cb){
 
 
     switch(ID(filter)){
diff --git a/src/meshlabplugins/filter_dirt/filter_dirt.h b/src/meshlabplugins/filter_dirt/filter_dirt.h
index 4c8ecc388..68fd46d38 100644
--- a/src/meshlabplugins/filter_dirt/filter_dirt.h
+++ b/src/meshlabplugins/filter_dirt/filter_dirt.h
@@ -66,8 +66,8 @@ public:
     virtual bool autoDialog(QAction *) {return true;}
     //      virtual void initParameterSet(QAction* filter,MeshModel &,RichParameterSet &){};
     virtual void initParameterSet(QAction *,MeshDocument &/*m*/, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction*  filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb);
-    virtual bool applyFilter(QAction * /*filter */, MeshModel &, const RichParameterList & /*parent*/, vcg::CallBackPos *) { assert(0); return false;} ;
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb);
+    virtual bool applyFilter(const QAction * /*filter */, MeshModel &, const RichParameterList & /*parent*/, vcg::CallBackPos *) { assert(0); return false;} ;
     virtual int postCondition(const QAction*) const;
     virtual FilterClass getClass (const QAction *) const;
     FILTER_ARITY filterArity(QAction*) const {return SINGLE_MESH;}
diff --git a/src/meshlabplugins/filter_fractal/filter_fractal.cpp b/src/meshlabplugins/filter_fractal/filter_fractal.cpp
index d8f924616..0042b42d2 100644
--- a/src/meshlabplugins/filter_fractal/filter_fractal.cpp
+++ b/src/meshlabplugins/filter_fractal/filter_fractal.cpp
@@ -255,7 +255,7 @@ void FilterFractal::initParameterSetForCratersGeneration(MeshDocument &md, RichP
     return;
 }
 
-bool FilterFractal::applyFilter(QAction* filter, MeshDocument &md, const RichParameterList &par, vcg::CallBackPos* cb)
+bool FilterFractal::applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList &par, vcg::CallBackPos* cb)
 {
   if(this->getClass(filter) == MeshFilterInterface::MeshCreation)
        md.addNewMesh("",this->filterName(ID(filter)));
diff --git a/src/meshlabplugins/filter_fractal/filter_fractal.h b/src/meshlabplugins/filter_fractal/filter_fractal.h
index a47431597..bca8fcd6d 100644
--- a/src/meshlabplugins/filter_fractal/filter_fractal.h
+++ b/src/meshlabplugins/filter_fractal/filter_fractal.h
@@ -49,7 +49,7 @@ public:
     void initParameterSet(QAction*, MeshModel&, RichParameterList &){assert(0);}
     void initParameterSet(QAction *, MeshDocument &, RichParameterList &);
 
-    bool applyFilter (QAction*  filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb);
+    bool applyFilter (const QAction* filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb);
 
     int postCondition(const QAction *action) const;
     FilterClass getClass(const QAction*) const;
diff --git a/src/meshlabplugins/filter_func/filter_func.cpp b/src/meshlabplugins/filter_func/filter_func.cpp
index 072da1c1f..868b8662d 100644
--- a/src/meshlabplugins/filter_func/filter_func.cpp
+++ b/src/meshlabplugins/filter_func/filter_func.cpp
@@ -373,7 +373,7 @@ void FilterFunctionPlugin::initParameterSet(QAction *action,MeshModel &m, RichPa
 }
 
 // The Real Core Function doing the actual mesh processing.
-bool FilterFunctionPlugin::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterFunctionPlugin::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
   if(this->getClass(filter) == MeshFilterInterface::MeshCreation)
     md.addNewMesh("",this->filterName(ID(filter)));
diff --git a/src/meshlabplugins/filter_func/filter_func.h b/src/meshlabplugins/filter_func/filter_func.h
index a57f87af4..97eb31fbf 100644
--- a/src/meshlabplugins/filter_func/filter_func.h
+++ b/src/meshlabplugins/filter_func/filter_func.h
@@ -81,7 +81,7 @@ public:
 	virtual int postCondition(const QAction *action) const;
 	virtual void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
 	virtual int getRequirements(QAction *);
-	virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     FILTER_ARITY filterArity(QAction* filter) const;
 
 
diff --git a/src/meshlabplugins/filter_geodesic/filter_geodesic.cpp b/src/meshlabplugins/filter_geodesic/filter_geodesic.cpp
index 3a87ceabb..6c21ee211 100644
--- a/src/meshlabplugins/filter_geodesic/filter_geodesic.cpp
+++ b/src/meshlabplugins/filter_geodesic/filter_geodesic.cpp
@@ -108,7 +108,7 @@ int FilterGeodesic::getRequirements(QAction *action)
 	return 0;
 }
 
-bool FilterGeodesic::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * /*cb*/)
+bool FilterGeodesic::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * /*cb*/)
 {
 	MeshModel &m=*(md.mm());
 	CMeshO::FaceIterator fi;
diff --git a/src/meshlabplugins/filter_geodesic/filter_geodesic.h b/src/meshlabplugins/filter_geodesic/filter_geodesic.h
index 42a84e27b..182d64710 100644
--- a/src/meshlabplugins/filter_geodesic/filter_geodesic.h
+++ b/src/meshlabplugins/filter_geodesic/filter_geodesic.h
@@ -56,7 +56,7 @@ class FilterGeodesic : public QObject, public MeshFilterInterface
 
 	FilterClass getClass(const QAction*) const;
 	int getRequirements(QAction *);
-	bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
 	void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
 	int postCondition(const QAction * filter) const;
 	FILTER_ARITY filterArity(QAction*) const {return SINGLE_MESH;}
diff --git a/src/meshlabplugins/filter_globalregistration/globalregistration.cpp b/src/meshlabplugins/filter_globalregistration/globalregistration.cpp
index 41229d2f8..eadee470e 100644
--- a/src/meshlabplugins/filter_globalregistration/globalregistration.cpp
+++ b/src/meshlabplugins/filter_globalregistration/globalregistration.cpp
@@ -166,7 +166,7 @@ float align ( CMeshO* refMesh, CMeshO* trgMesh,
 
 // The Real Core Function doing the actual mesh processing.
 // Move Vertex of a random quantity
-bool GlobalRegistrationPlugin::applyFilter(QAction */*filter*/,
+bool GlobalRegistrationPlugin::applyFilter(const QAction */*filter*/,
                                            MeshDocument &/*md*/,
                                            const RichParameterList & par,
                                            vcg::CallBackPos */*cb*/)
diff --git a/src/meshlabplugins/filter_globalregistration/globalregistration.h b/src/meshlabplugins/filter_globalregistration/globalregistration.h
index b31ffb2df..e476b9f8d 100644
--- a/src/meshlabplugins/filter_globalregistration/globalregistration.h
+++ b/src/meshlabplugins/filter_globalregistration/globalregistration.h
@@ -42,7 +42,7 @@ public:
     QString filterName(FilterIDType filter) const;
     QString filterInfo(FilterIDType filter) const;
     void initParameterSet(QAction *, MeshDocument &/*m*/, RichParameterList & /*parent*/);
-    bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+    bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     int postCondition(const QAction* ) const {return MeshModel::MM_VERTCOORD; }
     FilterClass getClass(const QAction* a) const;
     FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
diff --git a/src/meshlabplugins/filter_img_patch_param/filter_img_patch_param.cpp b/src/meshlabplugins/filter_img_patch_param/filter_img_patch_param.cpp
index 4810cd60f..460522b20 100644
--- a/src/meshlabplugins/filter_img_patch_param/filter_img_patch_param.cpp
+++ b/src/meshlabplugins/filter_img_patch_param/filter_img_patch_param.cpp
@@ -191,7 +191,7 @@ void FilterImgPatchParamPlugin::initParameterSet( QAction *act,
 }
 
 
-bool FilterImgPatchParamPlugin::applyFilter( QAction *act,
+bool FilterImgPatchParamPlugin::applyFilter(const QAction *act,
     MeshDocument &md,
     const RichParameterList &par,
     vcg::CallBackPos * /*cb*/ )
diff --git a/src/meshlabplugins/filter_img_patch_param/filter_img_patch_param.h b/src/meshlabplugins/filter_img_patch_param/filter_img_patch_param.h
index 1907f9ffe..3c620248d 100644
--- a/src/meshlabplugins/filter_img_patch_param/filter_img_patch_param.h
+++ b/src/meshlabplugins/filter_img_patch_param/filter_img_patch_param.h
@@ -112,7 +112,7 @@ public:
     virtual int         getRequirements( QAction *act );
     //virtual int         postCondition( QAction *act ) const;
 
-    virtual bool        applyFilter( QAction *act,
+    virtual bool        applyFilter(const QAction* act,
                                      MeshDocument &md,
                                      const RichParameterList &par,
                                      vcg::CallBackPos *cb );
diff --git a/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.cpp b/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.cpp
index 1235c2ca7..1f1c7bbf7 100644
--- a/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.cpp
+++ b/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.cpp
@@ -179,7 +179,7 @@ void FilterIsoParametrization::PrintStats(CMeshO *mesh)
   Log("stdDev Edge:  %5.2f",stdE/avE);
 }
 
-bool FilterIsoParametrization::applyFilter(QAction *filter, MeshDocument& md, const RichParameterList & par, vcg::CallBackPos  *cb)
+bool FilterIsoParametrization::applyFilter(const QAction *filter, MeshDocument& md, const RichParameterList & par, vcg::CallBackPos  *cb)
 {
   MeshModel* m = md.mm();  //get current mesh from document
   CMeshO *mesh=&m->cm;
diff --git a/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.h b/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.h
index 6416004e4..90cd5e637 100644
--- a/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.h
+++ b/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.h
@@ -55,7 +55,7 @@ class FilterIsoParametrization : public QObject, public MeshFilterInterface
   virtual int getRequirements(QAction *);
   
   virtual void initParameterSet(QAction *,MeshDocument&, RichParameterList & /*parent*/);
-  virtual bool applyFilter(QAction *filter, MeshDocument&, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
+  virtual bool applyFilter(const QAction* filter, MeshDocument&, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
   int postCondition(const QAction* filter) const;
   void PrintStats(CMeshO *mesh);
   FILTER_ARITY filterArity(QAction*) const;
diff --git a/src/meshlabplugins/filter_layer/filter_layer.cpp b/src/meshlabplugins/filter_layer/filter_layer.cpp
index 1fd63dd75..c6e7af8f5 100644
--- a/src/meshlabplugins/filter_layer/filter_layer.cpp
+++ b/src/meshlabplugins/filter_layer/filter_layer.cpp
@@ -178,7 +178,7 @@ void FilterLayerPlugin::initParameterSet(QAction *action, MeshDocument &md, Rich
 }
 
 // Core Function doing the actual mesh processing.
-bool FilterLayerPlugin::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterLayerPlugin::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
  CMeshO::FaceIterator fi;
  int numFacesSel,numVertSel;
diff --git a/src/meshlabplugins/filter_layer/filter_layer.h b/src/meshlabplugins/filter_layer/filter_layer.h
index 1264b2a56..11a8013ae 100644
--- a/src/meshlabplugins/filter_layer/filter_layer.h
+++ b/src/meshlabplugins/filter_layer/filter_layer.h
@@ -60,7 +60,7 @@ public:
     virtual QString filterInfo(FilterIDType filter) const;
     virtual FilterClass getClass(const QAction*) const;
     virtual void initParameterSet(QAction *,MeshDocument &/*m*/, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     int postCondition(const QAction *filter) const;
     FILTER_ARITY filterArity(QAction*) const;
 };
diff --git a/src/meshlabplugins/filter_measure/filter_measure.cpp b/src/meshlabplugins/filter_measure/filter_measure.cpp
index 35ff3c131..a29510409 100644
--- a/src/meshlabplugins/filter_measure/filter_measure.cpp
+++ b/src/meshlabplugins/filter_measure/filter_measure.cpp
@@ -171,7 +171,7 @@ void FilterMeasurePlugin::initParameterSet(QAction *action, MeshModel &m, RichPa
 	}
 }
 
-bool FilterMeasurePlugin::applyFilter(QAction* filter, MeshDocument& md, const RichParameterList& parlst, vcg::CallBackPos*)
+bool FilterMeasurePlugin::applyFilter(const QAction* filter, MeshDocument& md, const RichParameterList& parlst, vcg::CallBackPos*)
 {
 	switch (ID(filter)) {
 	case COMPUTE_TOPOLOGICAL_MEASURES:
diff --git a/src/meshlabplugins/filter_measure/filter_measure.h b/src/meshlabplugins/filter_measure/filter_measure.h
index 493962db7..50ff6e421 100644
--- a/src/meshlabplugins/filter_measure/filter_measure.h
+++ b/src/meshlabplugins/filter_measure/filter_measure.h
@@ -54,7 +54,7 @@ public:
 	FILTER_ARITY filterArity(QAction*) const;
 	int getPreConditions(QAction *action) const;
 	void initParameterSet(QAction* , MeshModel& m, RichParameterList& parlst);
-	bool applyFilter(QAction* filter, MeshDocument& md, const RichParameterList& parlst, vcg::CallBackPos*) ;
+	bool applyFilter(const QAction* filter, MeshDocument& md, const RichParameterList& parlst, vcg::CallBackPos*) ;
 	int postCondition(const QAction* ) const;
 
 private:
diff --git a/src/meshlabplugins/filter_meshing/meshfilter.cpp b/src/meshlabplugins/filter_meshing/meshfilter.cpp
index a500e4150..987a33ef5 100644
--- a/src/meshlabplugins/filter_meshing/meshfilter.cpp
+++ b/src/meshlabplugins/filter_meshing/meshfilter.cpp
@@ -674,7 +674,7 @@ void ApplyTransform(MeshDocument &md, const Matrix44m &tr, bool toAllFlag, bool
 }
 
 
-bool ExtraMeshFilterPlugin::applyFilter(QAction * filter, MeshDocument & md, const RichParameterList & par, vcg::CallBackPos * cb)
+bool ExtraMeshFilterPlugin::applyFilter(const QAction * filter, MeshDocument & md, const RichParameterList & par, vcg::CallBackPos * cb)
 {
 MeshModel & m = *md.mm();
 
diff --git a/src/meshlabplugins/filter_meshing/meshfilter.h b/src/meshlabplugins/filter_meshing/meshfilter.h
index 8a6ea95aa..3384a9224 100644
--- a/src/meshlabplugins/filter_meshing/meshfilter.h
+++ b/src/meshlabplugins/filter_meshing/meshfilter.h
@@ -89,7 +89,7 @@ public:
 
 	FilterClass getClass(const QAction*) const;
 	void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
-	bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
 	int postCondition(const QAction *filter) const;
 	int getPreCondition(QAction *filter) const;
 	FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
diff --git a/src/meshlabplugins/filter_mls/mlsplugin.cpp b/src/meshlabplugins/filter_mls/mlsplugin.cpp
index 6b0c8e32f..93f8ba307 100644
--- a/src/meshlabplugins/filter_mls/mlsplugin.cpp
+++ b/src/meshlabplugins/filter_mls/mlsplugin.cpp
@@ -357,7 +357,7 @@ void UpdateFaceNormalFromVertex(MeshType& m)
     }
 }
 
-bool MlsPlugin::applyFilter(QAction* filter, MeshDocument& md, const RichParameterList& par, vcg::CallBackPos* cb)
+bool MlsPlugin::applyFilter(const QAction* filter, MeshDocument& md, const RichParameterList& par, vcg::CallBackPos* cb)
 {
     int id = ID(filter);
 
diff --git a/src/meshlabplugins/filter_mls/mlsplugin.h b/src/meshlabplugins/filter_mls/mlsplugin.h
index 2bd0f9f99..ab0ea8873 100644
--- a/src/meshlabplugins/filter_mls/mlsplugin.h
+++ b/src/meshlabplugins/filter_mls/mlsplugin.h
@@ -68,7 +68,7 @@ public:
 	FilterClass getClass(const QAction *a) const;
     virtual void initParameterSet(QAction *,MeshDocument &md, RichParameterList &parent);
 	virtual int getRequirements(QAction *action);
-	virtual bool applyFilter(QAction *filter, MeshDocument &m, const RichParameterList &parent, vcg::CallBackPos *cb) ;
+	virtual bool applyFilter(const QAction* filter, MeshDocument &m, const RichParameterList &parent, vcg::CallBackPos *cb) ;
     FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
 };
 
diff --git a/src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.cpp b/src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.cpp
index d138c3313..e6b336483 100644
--- a/src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.cpp
+++ b/src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.cpp
@@ -158,7 +158,7 @@ void FilterMutualGlobal::initParameterSet(QAction *action,MeshDocument & md, Ric
 
 // The Real Core Function doing the actual mesh processing.
 // Move Vertex of a random quantity
-bool FilterMutualGlobal::applyFilter(QAction *action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterMutualGlobal::applyFilter(const QAction *action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
 	QElapsedTimer filterTime;
 	filterTime.start();
diff --git a/src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.h b/src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.h
index 664e5506f..352921e1e 100644
--- a/src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.h
+++ b/src/meshlabplugins/filter_mutualglobal/filter_mutualglobal.h
@@ -55,7 +55,7 @@ public:
 	QString filterName(FilterIDType filter) const;
 	QString filterInfo(FilterIDType filter) const;
 	void initParameterSet(QAction *,MeshDocument & md, RichParameterList & /*parent*/);
-	bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
 	int postCondition(const QAction*) const { return MeshModel::MM_NONE; };
 	FilterClass getClass(const QAction* a) const;
 	QString filterScriptFunctionName(FilterIDType filterID);
diff --git a/src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.cpp b/src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.cpp
index 03a2c7c2f..2317d7fa5 100644
--- a/src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.cpp
+++ b/src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.cpp
@@ -110,7 +110,7 @@ void FilterMutualInfoPlugin::initParameterSet(QAction *action,MeshDocument & /*m
 	}
 }
 
-bool FilterMutualInfoPlugin::applyFilter(QAction *action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos* )
+bool FilterMutualInfoPlugin::applyFilter(const QAction *action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos* )
 {
 	switch(ID(action))	 {
 	case FP_IMAGE_MUTUALINFO :
diff --git a/src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.h b/src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.h
index 82f04cbd7..80a59040f 100644
--- a/src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.h
+++ b/src/meshlabplugins/filter_mutualinfo/filter_mutualinfo.h
@@ -48,7 +48,7 @@ public:
 	FilterClass getClass(const QAction* a) const;
 	FILTER_ARITY filterArity(QAction *) const;
 	void initParameterSet(QAction *, MeshDocument &, RichParameterList & /*parent*/);
-	bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
 	int postCondition(const QAction*) const;
 
 private:
diff --git a/src/meshlabplugins/filter_plymc/filter_plymc.cpp b/src/meshlabplugins/filter_plymc/filter_plymc.cpp
index 1eefbcea5..ec45d0880 100644
--- a/src/meshlabplugins/filter_plymc/filter_plymc.cpp
+++ b/src/meshlabplugins/filter_plymc/filter_plymc.cpp
@@ -122,7 +122,7 @@ void PlyMCPlugin::initParameterSet(QAction *action,MeshModel &m, RichParameterLi
 }
 
 // The Real Core Function doing the actual mesh processing.
-bool PlyMCPlugin::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * cb)
+bool PlyMCPlugin::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * cb)
 {
   switch(ID(filter))
   {
diff --git a/src/meshlabplugins/filter_plymc/filter_plymc.h b/src/meshlabplugins/filter_plymc/filter_plymc.h
index 3e56ae694..199639ad6 100644
--- a/src/meshlabplugins/filter_plymc/filter_plymc.h
+++ b/src/meshlabplugins/filter_plymc/filter_plymc.h
@@ -44,7 +44,7 @@ public:
     virtual QString filterName(FilterIDType filter) const;
     virtual QString filterInfo(FilterIDType filter) const;
     virtual void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     FilterClass getClass(const QAction* a) const;
     MeshFilterInterface::FILTER_ARITY filterArity(QAction * filter) const;
     int postCondition(const QAction *filter) const;
diff --git a/src/meshlabplugins/filter_qhull/filter_qhull.cpp b/src/meshlabplugins/filter_qhull/filter_qhull.cpp
index 0ac07de47..baff4f9e3 100644
--- a/src/meshlabplugins/filter_qhull/filter_qhull.cpp
+++ b/src/meshlabplugins/filter_qhull/filter_qhull.cpp
@@ -198,7 +198,7 @@ void QhullPlugin::initParameterSet(QAction *action,MeshModel &m, RichParameterLi
 }
 
 // The Real Core Function doing the actual mesh processing.
-bool QhullPlugin::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos */* cb*/)
+bool QhullPlugin::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos */* cb*/)
 {
     switch(ID(filter))
     {
diff --git a/src/meshlabplugins/filter_qhull/filter_qhull.h b/src/meshlabplugins/filter_qhull/filter_qhull.h
index 3dc1c0c7d..f0fe15075 100644
--- a/src/meshlabplugins/filter_qhull/filter_qhull.h
+++ b/src/meshlabplugins/filter_qhull/filter_qhull.h
@@ -59,7 +59,7 @@ public:
     virtual QString filterName(FilterIDType filter) const;
     virtual QString filterInfo(FilterIDType filter) const;
     virtual void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction *filter, MeshDocument &m, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+    virtual bool applyFilter(const QAction* filter, MeshDocument &m, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     virtual FilterClass getClass(const QAction*) const;
     FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
 };
diff --git a/src/meshlabplugins/filter_quality/filterqualitymapper.cpp b/src/meshlabplugins/filter_quality/filterqualitymapper.cpp
index 4f31a3a23..990345231 100644
--- a/src/meshlabplugins/filter_quality/filterqualitymapper.cpp
+++ b/src/meshlabplugins/filter_quality/filterqualitymapper.cpp
@@ -125,7 +125,7 @@ void QualityMapperFilter::initParameterSet(QAction *action,MeshModel &m, RichPar
 
 // The Real Core Function doing the actual mesh processing.
 // Apply color to mesh vertices
-bool QualityMapperFilter::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool QualityMapperFilter::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
     MeshModel &m=*(md.mm());
 	m.updateDataMask(MeshModel::MM_VERTCOLOR);
diff --git a/src/meshlabplugins/filter_quality/filterqualitymapper.h b/src/meshlabplugins/filter_quality/filterqualitymapper.h
index f969179c1..cf076b900 100644
--- a/src/meshlabplugins/filter_quality/filterqualitymapper.h
+++ b/src/meshlabplugins/filter_quality/filterqualitymapper.h
@@ -75,7 +75,7 @@ public:
     int getPreConditions(QAction *) const;
     int postCondition(const QAction* ) const;
     virtual void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     virtual FilterClass getClass(const QAction*) const;
     FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
 };
diff --git a/src/meshlabplugins/filter_sample/filter_sample.cpp b/src/meshlabplugins/filter_sample/filter_sample.cpp
index 0ba71708f..221feac21 100644
--- a/src/meshlabplugins/filter_sample/filter_sample.cpp
+++ b/src/meshlabplugins/filter_sample/filter_sample.cpp
@@ -153,7 +153,7 @@ void FilterSamplePlugin::initParameterSet(QAction *action,MeshModel &m, RichPara
  * @param cb: callback object to tell MeshLab the percentage of execution of the filter
  * @return true if the filter has been applied correctly, false otherwise
  */
-bool FilterSamplePlugin::applyFilter(QAction * action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterSamplePlugin::applyFilter(const QAction * action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
 	switch(ID(action)) {
 	case FP_MOVE_VERTEX :
diff --git a/src/meshlabplugins/filter_sample/filter_sample.h b/src/meshlabplugins/filter_sample/filter_sample.h
index 91bc4bc8e..e0ca73335 100644
--- a/src/meshlabplugins/filter_sample/filter_sample.h
+++ b/src/meshlabplugins/filter_sample/filter_sample.h
@@ -61,7 +61,7 @@ public:
 	int getPreConditions(QAction *) const;
 	int postCondition(const QAction* ) const;
 	void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
-	bool applyFilter(QAction *action, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
+	bool applyFilter(const QAction* action, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
 
 private:
 	bool vertexDisplacement(
diff --git a/src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.cpp b/src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.cpp
index dfb49506c..d87d83d23 100644
--- a/src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.cpp
+++ b/src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.cpp
@@ -119,7 +119,7 @@ void ExtraSampleDynPlugin::initParameterSet(QAction *action,MeshModel &/*m*/, Ri
 
 // The Real Core Function doing the actual mesh processing.
 // It changes the color of the mesh according to a perlin noise function
-bool ExtraSampleDynPlugin::applyFilter(QAction *, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *)
+bool ExtraSampleDynPlugin::applyFilter(const QAction *, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *)
 {
     MeshModel &m=*(md.mm());
     const Color4b baseColor = par.getColor4b("baseColor");
diff --git a/src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.h b/src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.h
index 4a881fda4..24dc477a3 100644
--- a/src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.h
+++ b/src/meshlabplugins/filter_sample_dyn/filter_sample_dyn.h
@@ -44,7 +44,7 @@ public:
     virtual QString filterInfo(FilterIDType filter) const;
     virtual void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
     virtual int postCondition(const QAction* ) const {return MeshModel::MM_VERTCOLOR;};
-    virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+    virtual bool applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
     virtual FilterClass getClass(const QAction*) const;
     FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
 };
diff --git a/src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.cpp b/src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.cpp
index 0d0df867c..60af09113 100644
--- a/src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.cpp
+++ b/src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.cpp
@@ -108,7 +108,7 @@ void ExtraSampleGPUPlugin::initParameterSet(QAction * action, MeshModel & m, Ric
 
 // The Real Core Function doing the actual mesh processing.
 // Move Vertex of a random quantity
-bool ExtraSampleGPUPlugin::applyFilter(QAction * a, MeshDocument & md , const RichParameterList & par, vcg::CallBackPos * /*cb*/)
+bool ExtraSampleGPUPlugin::applyFilter(const QAction * a, MeshDocument & md , const RichParameterList & par, vcg::CallBackPos * /*cb*/)
 {
 	switch(ID(a))
 	{
diff --git a/src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.h b/src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.h
index 86cb6095d..7eea9b47b 100644
--- a/src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.h
+++ b/src/meshlabplugins/filter_sample_gpu/filter_sample_gpu.h
@@ -55,7 +55,7 @@ public:
 
 	QString filterName(FilterIDType filter) const;
 	QString filterInfo(FilterIDType filter) const;
-	bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
 	FilterClass getClass(const QAction* a) const;
 };
 
diff --git a/src/meshlabplugins/filter_sampling/filter_sampling.cpp b/src/meshlabplugins/filter_sampling/filter_sampling.cpp
index b447fce2c..fced06b0b 100644
--- a/src/meshlabplugins/filter_sampling/filter_sampling.cpp
+++ b/src/meshlabplugins/filter_sampling/filter_sampling.cpp
@@ -696,7 +696,7 @@ void FilterDocSampling::initParameterSet(QAction *action, MeshDocument & md, Ric
   }
 }
 
-bool FilterDocSampling::applyFilter(QAction *action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterDocSampling::applyFilter(const QAction *action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
 switch(ID(action))
 {
diff --git a/src/meshlabplugins/filter_sampling/filter_sampling.h b/src/meshlabplugins/filter_sampling/filter_sampling.h
index b196e2a98..608ed1882 100644
--- a/src/meshlabplugins/filter_sampling/filter_sampling.h
+++ b/src/meshlabplugins/filter_sampling/filter_sampling.h
@@ -55,7 +55,7 @@ class FilterDocSampling : public QObject, public MeshFilterInterface
   QString filterName(FilterIDType filter) const;
   QString filterInfo(FilterIDType filter) const;
   void initParameterSet(QAction *,MeshDocument &/*m*/, RichParameterList & /*parent*/);
-  bool applyFilter(QAction *filter, MeshDocument &m, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+  bool applyFilter(const QAction* filter, MeshDocument &m, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
   int getRequirements(QAction *action);
   int postCondition(const QAction* ) const;
   FilterClass getClass(const QAction*) const;
diff --git a/src/meshlabplugins/filter_screened_poisson/filter_screened_poisson.cpp b/src/meshlabplugins/filter_screened_poisson/filter_screened_poisson.cpp
index 54807e5d0..73ea66015 100644
--- a/src/meshlabplugins/filter_screened_poisson/filter_screened_poisson.cpp
+++ b/src/meshlabplugins/filter_screened_poisson/filter_screened_poisson.cpp
@@ -99,7 +99,7 @@ int FilterScreenedPoissonPlugin::getRequirements(QAction* a)
 	}
 }
 
-bool FilterScreenedPoissonPlugin::applyFilter(QAction* filter, MeshDocument& md, const RichParameterList& params, vcg::CallBackPos* cb)
+bool FilterScreenedPoissonPlugin::applyFilter(const QAction* filter, MeshDocument& md, const RichParameterList& params, vcg::CallBackPos* cb)
 {
 	bool currDirChanged=false;
 	QDir currDir = QDir::current();
diff --git a/src/meshlabplugins/filter_screened_poisson/filter_screened_poisson.h b/src/meshlabplugins/filter_screened_poisson/filter_screened_poisson.h
index 6c9520d1e..eea152123 100644
--- a/src/meshlabplugins/filter_screened_poisson/filter_screened_poisson.h
+++ b/src/meshlabplugins/filter_screened_poisson/filter_screened_poisson.h
@@ -47,8 +47,7 @@ public:
 	FilterClass getClass(const QAction* a) const;
 	int getRequirements(QAction* a);
 
-	bool applyFilter(
-			QAction* filter,
+	bool applyFilter(const QAction* filter,
 			MeshDocument& md,
 			const RichParameterList& params,
 			vcg::CallBackPos* cb) ;
diff --git a/src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.cpp b/src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.cpp
index faaa1480f..91dd3d48d 100644
--- a/src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.cpp
+++ b/src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.cpp
@@ -143,7 +143,7 @@ QString SdfGpuPlugin::filterInfo(FilterIDType filterId) const
     return QString("");
 }
 
-bool SdfGpuPlugin::applyFilter(QAction */*filter*/, MeshDocument &md, const RichParameterList & pars, vcg::CallBackPos *cb)
+bool SdfGpuPlugin::applyFilter(const QAction */*filter*/, MeshDocument &md, const RichParameterList & pars, vcg::CallBackPos *cb)
 {
     MeshModel* mm = md.mm();
 
diff --git a/src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.h b/src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.h
index 32d402f0c..e586c212f 100644
--- a/src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.h
+++ b/src/meshlabplugins/filter_sdfgpu/filter_sdfgpu.h
@@ -37,7 +37,7 @@ public:
     FILTER_ARITY filterArity(QAction *act) const;
 
     //Main plugin function
-    bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb);
+    bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb);
 
     //Parameters init for user interface
     virtual void initParameterSet(QAction *action, MeshModel &m, RichParameterList &parlst);
diff --git a/src/meshlabplugins/filter_sdfgpu/filterinterface.h b/src/meshlabplugins/filter_sdfgpu/filterinterface.h
index 46a5c20e6..e1f450d27 100644
--- a/src/meshlabplugins/filter_sdfgpu/filterinterface.h
+++ b/src/meshlabplugins/filter_sdfgpu/filterinterface.h
@@ -153,7 +153,7 @@ private:
   int postCondition(const QAction*) const{
     return MeshModel::MM_NONE;
   }
-  bool applyFilter(QAction *, MeshDocument &md, const RichParameterList& par, vcg::CallBackPos * cb){
+  bool applyFilter(const QAction *, MeshDocument &md, const RichParameterList& par, vcg::CallBackPos * cb){
     return applyFilter(md, par, cb);
   }
   virtual void initParameterSet(QAction *, MeshDocument &md, RichParameterList &par){
diff --git a/src/meshlabplugins/filter_select/meshselect.cpp b/src/meshlabplugins/filter_select/meshselect.cpp
index c1190d11a..b48fcbe77 100644
--- a/src/meshlabplugins/filter_select/meshselect.cpp
+++ b/src/meshlabplugins/filter_select/meshselect.cpp
@@ -301,7 +301,7 @@ void SelectionFilterPlugin::initParameterSet(QAction *action, MeshModel &m, Rich
  }
 }
 
-bool SelectionFilterPlugin::applyFilter(QAction *action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * /*cb*/)
+bool SelectionFilterPlugin::applyFilter(const QAction *action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * /*cb*/)
 {
 	if (md.mm() == NULL)
 		return false;
diff --git a/src/meshlabplugins/filter_select/meshselect.h b/src/meshlabplugins/filter_select/meshselect.h
index ada4af3d5..33cea7870 100644
--- a/src/meshlabplugins/filter_select/meshselect.h
+++ b/src/meshlabplugins/filter_select/meshselect.h
@@ -78,7 +78,7 @@ class SelectionFilterPlugin : public QObject, public MeshFilterInterface
   int getPreConditions(QAction *) const;
   int postCondition(const QAction* ) const;
   int getRequirements(QAction *);
-  bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+  bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
   FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
 };
 
diff --git a/src/meshlabplugins/filter_sketchfab/filter_sketchfab.cpp b/src/meshlabplugins/filter_sketchfab/filter_sketchfab.cpp
index c4e31dc85..6566d09f2 100644
--- a/src/meshlabplugins/filter_sketchfab/filter_sketchfab.cpp
+++ b/src/meshlabplugins/filter_sketchfab/filter_sketchfab.cpp
@@ -122,7 +122,7 @@ void FilterSketchFabPlugin::initParameterSet(QAction* action, MeshModel&, RichPa
 	}
 }
 
-bool FilterSketchFabPlugin::applyFilter(QAction * action, MeshDocument& md, const RichParameterList& par, vcg::CallBackPos* cb)
+bool FilterSketchFabPlugin::applyFilter(const QAction * action, MeshDocument& md, const RichParameterList& par, vcg::CallBackPos* cb)
 {
 	switch (ID(action)) {
 	case FP_SKETCHFAB:
diff --git a/src/meshlabplugins/filter_sketchfab/filter_sketchfab.h b/src/meshlabplugins/filter_sketchfab/filter_sketchfab.h
index 36737ae2c..8e7a0e51b 100644
--- a/src/meshlabplugins/filter_sketchfab/filter_sketchfab.h
+++ b/src/meshlabplugins/filter_sketchfab/filter_sketchfab.h
@@ -46,7 +46,7 @@ public:
 	int getPreConditions(QAction *) const;
 	int postCondition(const QAction* ) const;
 	void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
-	bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
 
 public slots:
 	void finished();
diff --git a/src/meshlabplugins/filter_ssynth/filter_ssynth.cpp b/src/meshlabplugins/filter_ssynth/filter_ssynth.cpp
index 345c783e1..ede27bfd3 100644
--- a/src/meshlabplugins/filter_ssynth/filter_ssynth.cpp
+++ b/src/meshlabplugins/filter_ssynth/filter_ssynth.cpp
@@ -78,7 +78,7 @@ void FilterSSynth::openX3D(const QString &fileName, MeshModel &m, int& mask, vcg
     delete(info);
 }
 
-bool FilterSSynth::applyFilter(QAction*  filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterSSynth::applyFilter(const QAction*  filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
     md.addNewMesh("",this->filterName(ID(filter)));
     QWidget *  parent=(QWidget*)this->parent();
diff --git a/src/meshlabplugins/filter_ssynth/filter_ssynth.h b/src/meshlabplugins/filter_ssynth/filter_ssynth.h
index d9cf2e947..48f3bbbbf 100644
--- a/src/meshlabplugins/filter_ssynth/filter_ssynth.h
+++ b/src/meshlabplugins/filter_ssynth/filter_ssynth.h
@@ -46,7 +46,7 @@ public:
     virtual int getRequirements(QAction *);
     virtual void initParameterSet(QAction* /*filter*/,MeshModel &,RichParameterList &){};
     virtual void initParameterSet(QAction *,MeshDocument &/*m*/, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction*  filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb);
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb);
     virtual FilterClass getClass(const QAction* filter) const;
     void setAttributes(CMeshO::VertexIterator &vi, CMeshO &m);
     static void openX3D(const QString &fileName, MeshModel &m, int& mask, vcg::CallBackPos *cb, QWidget *parent=0);
diff --git a/src/meshlabplugins/filter_texture/filter_texture.cpp b/src/meshlabplugins/filter_texture/filter_texture.cpp
index 360add8a4..130f36dda 100644
--- a/src/meshlabplugins/filter_texture/filter_texture.cpp
+++ b/src/meshlabplugins/filter_texture/filter_texture.cpp
@@ -342,7 +342,7 @@ T log_2(const T num)
 }
 
 // The Real Core Function doing the actual mesh processing.
-bool FilterTexturePlugin::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList &par, CallBackPos *cb)
+bool FilterTexturePlugin::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList &par, CallBackPos *cb)
 {
     MeshModel &m=*(md.mm());
     switch(ID(filter))     {
diff --git a/src/meshlabplugins/filter_texture/filter_texture.h b/src/meshlabplugins/filter_texture/filter_texture.h
index bd9056c45..025c78919 100644
--- a/src/meshlabplugins/filter_texture/filter_texture.h
+++ b/src/meshlabplugins/filter_texture/filter_texture.h
@@ -59,7 +59,7 @@ public:
     virtual QString filterName(FilterIDType filter) const;
     virtual QString filterInfo(FilterIDType filter) const;
     virtual void initParameterSet(QAction *,MeshDocument &/*m*/, RichParameterList & /*parent*/);
-    virtual bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
+    virtual bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb);
     virtual int getRequirements(QAction *);
     virtual int getPreConditions(QAction *) const;
     virtual int postCondition(const QAction* ) const;
diff --git a/src/meshlabplugins/filter_trioptimize/filter_trioptimize.cpp b/src/meshlabplugins/filter_trioptimize/filter_trioptimize.cpp
index b32906e97..7683f2d57 100644
--- a/src/meshlabplugins/filter_trioptimize/filter_trioptimize.cpp
+++ b/src/meshlabplugins/filter_trioptimize/filter_trioptimize.cpp
@@ -171,7 +171,7 @@ QString TriOptimizePlugin::pluginName() const
 	return {};
 }
 
- TriOptimizePlugin::FilterClass TriOptimizePlugin::getClass(QAction *action)
+ TriOptimizePlugin::FilterClass TriOptimizePlugin::getClass(const QAction *action)
 {
 	switch(ID(action)) {
 		case FP_PLANAR_EDGE_FLIP:             return MeshFilterInterface::Remeshing;
@@ -262,7 +262,7 @@ void TriOptimizePlugin::initParameterSet(QAction *action, MeshModel &m, RichPara
 
 // The Real Core Function doing the actual mesh processing.
 // Run mesh optimization
-bool TriOptimizePlugin::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool TriOptimizePlugin::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
     MeshModel &m=*(md.mm());
     float limit = -std::numeric_limits<float>::epsilon();
diff --git a/src/meshlabplugins/filter_trioptimize/filter_trioptimize.h b/src/meshlabplugins/filter_trioptimize/filter_trioptimize.h
index 6cff6c141..7b5a24e89 100644
--- a/src/meshlabplugins/filter_trioptimize/filter_trioptimize.h
+++ b/src/meshlabplugins/filter_trioptimize/filter_trioptimize.h
@@ -48,9 +48,9 @@ public:
 	QString filterName(FilterIDType filter) const;
 	QString filterInfo(FilterIDType filter) const;
 	void initParameterSet(QAction *,MeshModel &/*m*/, RichParameterList & /*parent*/);
-	bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList &/*parent*/, vcg::CallBackPos * cb) ;
+	bool applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList &/*parent*/, vcg::CallBackPos * cb) ;
 	int getRequirements(QAction *);
-	FilterClass getClass(QAction *);
+	FilterClass getClass(const QAction *);
 	int postCondition(const QAction* ) const;
     FILTER_ARITY filterArity(QAction *) const {return SINGLE_MESH;}
 
diff --git a/src/meshlabplugins/filter_unsharp/filter_unsharp.cpp b/src/meshlabplugins/filter_unsharp/filter_unsharp.cpp
index f562ef174..48be62328 100644
--- a/src/meshlabplugins/filter_unsharp/filter_unsharp.cpp
+++ b/src/meshlabplugins/filter_unsharp/filter_unsharp.cpp
@@ -405,7 +405,7 @@ void FilterUnsharp::initParameterSet(QAction *action, MeshDocument &md, RichPara
   }
 }
 
-bool FilterUnsharp::applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * cb)
+bool FilterUnsharp::applyFilter(const QAction *filter, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos * cb)
 {
     MeshModel &m=*(md.mm());
     switch(ID(filter))
diff --git a/src/meshlabplugins/filter_unsharp/filter_unsharp.h b/src/meshlabplugins/filter_unsharp/filter_unsharp.h
index f0a0e90fb..0f8c9fa98 100644
--- a/src/meshlabplugins/filter_unsharp/filter_unsharp.h
+++ b/src/meshlabplugins/filter_unsharp/filter_unsharp.h
@@ -72,7 +72,7 @@ class FilterUnsharp : public QObject, public MeshFilterInterface
 	QString filterInfo(FilterIDType filter) const;
 	FilterClass getClass(const QAction*) const;
 	int getRequirements(QAction *);
-	bool applyFilter(QAction *filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
+	bool applyFilter(const QAction* filter, MeshDocument &md, const RichParameterList & /*parent*/, vcg::CallBackPos * cb) ;
 	void initParameterSet(QAction *action, MeshDocument &/*m*/, RichParameterList & parlst);
 	int postCondition(const QAction* ) const;
 	int getPreConditions(QAction *) const;
diff --git a/src/meshlabplugins/filter_voronoi/filter_voronoi.cpp b/src/meshlabplugins/filter_voronoi/filter_voronoi.cpp
index 14e172603..a671e98ce 100644
--- a/src/meshlabplugins/filter_voronoi/filter_voronoi.cpp
+++ b/src/meshlabplugins/filter_voronoi/filter_voronoi.cpp
@@ -95,7 +95,7 @@ QString FilterVoronoiPlugin::filterInfo(FilterIDType filterId) const
 	}
 }
 
-FilterVoronoiPlugin::FilterClass FilterVoronoiPlugin::getClass(QAction* a)
+FilterVoronoiPlugin::FilterClass FilterVoronoiPlugin::getClass(const QAction* a) const
 {
 	switch(ID(a)) {
 	case VORONOI_SAMPLING :
@@ -211,7 +211,7 @@ int FilterVoronoiPlugin::getPreConditions(QAction* action) const
 	}
 }
 
-bool FilterVoronoiPlugin::applyFilter(QAction * action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
+bool FilterVoronoiPlugin::applyFilter(const QAction * action, MeshDocument &md, const RichParameterList & par, vcg::CallBackPos *cb)
 {
 	switch(ID(action))	 {
 	case VORONOI_SAMPLING :
diff --git a/src/meshlabplugins/filter_voronoi/filter_voronoi.h b/src/meshlabplugins/filter_voronoi/filter_voronoi.h
index be21e78f4..9507d47e8 100644
--- a/src/meshlabplugins/filter_voronoi/filter_voronoi.h
+++ b/src/meshlabplugins/filter_voronoi/filter_voronoi.h
@@ -47,11 +47,11 @@ public:
 	QString pluginName() const;
 	QString filterName(FilterIDType filter) const;
 	QString filterInfo(FilterIDType filter) const;
-	FilterClass getClass(QAction* a);
+	FilterClass getClass(const QAction* a) const;
 	FILTER_ARITY filterArity(QAction* a) const;
 	void initParameterSet(QAction* action, MeshModel& m, RichParameterList& par);
 	int getPreConditions(QAction* action) const;
-	bool applyFilter(QAction* action, MeshDocument& md, const RichParameterList& par, vcg::CallBackPos* cb) ;
+	bool applyFilter(const QAction* action, MeshDocument& md, const RichParameterList& par, vcg::CallBackPos* cb) ;
 	int postCondition(const QAction* ) const;
 
 private: