diff --git a/src/fgt/filter_colorproc/filter_colorproc.cpp b/src/fgt/filter_colorproc/filter_colorproc.cpp
index d9d2d2d69..1426b775e 100644
--- a/src/fgt/filter_colorproc/filter_colorproc.cpp
+++ b/src/fgt/filter_colorproc/filter_colorproc.cpp
@@ -454,11 +454,9 @@ int FilterColorProc::getPreConditions( QAction * filter ) const
 		case CP_SCATTER_PER_MESH :
 		case CP_PERLIN_COLOR :
 		case CP_COLOR_NOISE :
-		{
-			return MeshFilterInterface::FP_Generic;
-			break;
-		}
-		case CP_THRESHOLDING :
+      return MeshModel::MM_NONE;
+
+    case CP_THRESHOLDING :
 		case CP_BRIGHTNESS :
 		case CP_CONTRAST :
 		case CP_CONTR_BRIGHT :
@@ -468,11 +466,9 @@ int FilterColorProc::getPreConditions( QAction * filter ) const
 		case CP_DESATURATION :
 		case CP_WHITE_BAL :
 		case CP_LEVELS :
-		{
-			return MeshFilterInterface::FP_VertexColor;	
-			break;
-		}
-		default: assert(0); return MeshFilterInterface::FP_Generic;
+      return MeshModel::MM_VERTCOLOR;
+
+    default: assert(0); return MeshModel::MM_NONE;
 	}
 }
 
diff --git a/src/fgt/filter_quality/filterqualitymapper.cpp b/src/fgt/filter_quality/filterqualitymapper.cpp
index 5d8784f52..f2dd09124 100644
--- a/src/fgt/filter_quality/filterqualitymapper.cpp
+++ b/src/fgt/filter_quality/filterqualitymapper.cpp
@@ -180,10 +180,10 @@ int QualityMapperFilter::getPreConditions( QAction * a) const
 	switch(ID(a))
 	{
 		case FP_QUALITY_MAPPER :           
-			return MeshFilterInterface::FP_VertexQuality;
+      return MeshModel::MM_VERTQUALITY;
 		default :  
 			assert(0);			
-			return MeshFilterInterface::FP_Generic;
+      return MeshModel::MM_NONE;
 	} 
 }
 
diff --git a/src/meshlabplugins/filter_colorize/meshcolorize.cpp b/src/meshlabplugins/filter_colorize/meshcolorize.cpp
index e787f2506..de29bd89b 100644
--- a/src/meshlabplugins/filter_colorize/meshcolorize.cpp
+++ b/src/meshlabplugins/filter_colorize/meshcolorize.cpp
@@ -419,27 +419,27 @@ int ExtraMeshColorizePlugin::getPreConditions(QAction *a) const
 		case   CP_RANDOM_FACE:	
     case   CP_DISCRETE_CURVATURE:
     case   CP_COLOR_NON_TOPO_COHERENT:
-				return MeshFilterInterface::FP_Face;
+      return MeshModel::MM_FACENUMBER;
 
   case   CP_CLAMP_QUALITY:
     case   CP_MAP_QUALITY_INTO_COLOR:
-				return MeshFilterInterface::FP_VertexQuality;
+        return MeshModel::MM_VERTQUALITY;
 
     case   CP_FACE_TO_VERTEX:
     case   CP_FACE_SMOOTH:
-				return MeshFilterInterface::FP_FaceColor;
+        return MeshModel::MM_FACECOLOR;
 
     case   CP_VERTEX_SMOOTH:
     case   CP_VERTEX_TO_FACE:
-				return MeshFilterInterface::FP_VertexColor;
+        return MeshModel::MM_VERTCOLOR;
 
 	  case   CP_TEXTURE_TO_VERTEX:
     case   CP_TEXBORDER: 
-				return MeshFilterInterface::FP_WedgeTexCoord;
+        return MeshModel::MM_WEDGTEXCOORD;
 
     default: assert(0);
 	}
-	return MeshFilterInterface::FP_Generic;
+  return MeshModel::MM_NONE;
 }
 
 int ExtraMeshColorizePlugin::postCondition( QAction* a ) const 
diff --git a/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.cpp b/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.cpp
index c4a6f6454..912486cac 100644
--- a/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.cpp
+++ b/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.cpp
@@ -441,9 +441,4 @@ int FilterIsoParametrization::postCondition( QAction* /*filter*/ ) const
 	 return MeshModel::MM_UNKNOWN;
 }
 
-int FilterIsoParametrization::getPreConditions( QAction * /*filter*/ ) const
-{
-	return MeshFilterInterface::FP_Generic;
-}
-
 Q_EXPORT_PLUGIN(FilterIsoParametrization)
diff --git a/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.h b/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.h
index 3a20ec1cc..9eb58914b 100644
--- a/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.h
+++ b/src/meshlabplugins/filter_isoparametrization/filter_isoparametrization.h
@@ -58,7 +58,6 @@ class FilterIsoParametrization : public QObject, public MeshFilterInterface
         virtual void initParameterSet(QAction *,MeshDocument&, RichParameterSet & /*parent*/);
         virtual bool applyFilter(QAction *filter, MeshDocument&, RichParameterSet & /*parent*/, vcg::CallBackPos * cb);
         int postCondition(QAction* filter) const;
-		int getPreConditions(QAction *) const;
 		void PrintStats(CMeshO *mesh);
 		AbstractMesh abs_mesh;
 		ParamMesh para_mesh;
diff --git a/src/meshlabplugins/filter_texture/filter_texture.cpp b/src/meshlabplugins/filter_texture/filter_texture.cpp
index 7ebabd4f7..4b1bc948d 100644
--- a/src/meshlabplugins/filter_texture/filter_texture.cpp
+++ b/src/meshlabplugins/filter_texture/filter_texture.cpp
@@ -81,16 +81,16 @@ int FilterTexturePlugin::getPreConditions(QAction *a) const
 {
 	switch (ID(a))
 	{
-		case FP_UV_TO_COLOR : return MeshFilterInterface::FP_VertexTexCoord;
-		case FP_UV_WEDGE_TO_VERTEX : return MeshFilterInterface::FP_WedgeTexCoord;
-		case FP_BASIC_TRIANGLE_MAPPING : return MeshFilterInterface::FP_Face;
-		case FP_SET_TEXTURE : return MeshFilterInterface::FP_WedgeTexCoord;
-		case FP_COLOR_TO_TEXTURE : return MeshFilterInterface::FP_WedgeTexCoord + MeshFilterInterface::FP_VertexColor;
-		case FP_TRANSFER_TO_TEXTURE : return FP_Generic;
-		case FP_TEX_TO_VCOLOR_TRANSFER : return FP_Generic;
+    case FP_UV_TO_COLOR : return MeshModel::MM_VERTTEXCOORD;
+    case FP_UV_WEDGE_TO_VERTEX : return MeshModel::MM_WEDGTEXCOORD;
+    case FP_BASIC_TRIANGLE_MAPPING : return MeshModel::MM_FACENUMBER;
+    case FP_SET_TEXTURE : return MeshModel::MM_WEDGTEXCOORD;
+    case FP_COLOR_TO_TEXTURE : return MeshModel::MM_VERTCOLOR;
+    case FP_TRANSFER_TO_TEXTURE : return MeshModel::MM_NONE;
+    case FP_TEX_TO_VCOLOR_TRANSFER : return MeshModel::MM_NONE;
 		default: assert(0);
 	}
-	return MeshFilterInterface::FP_Generic;
+  return MeshModel::MM_NONE;
 }
 
 int FilterTexturePlugin::getRequirements(QAction *a)
diff --git a/src/meshlabplugins/filter_unsharp/filter_unsharp.cpp b/src/meshlabplugins/filter_unsharp/filter_unsharp.cpp
index 47c1041ec..72070360e 100644
--- a/src/meshlabplugins/filter_unsharp/filter_unsharp.cpp
+++ b/src/meshlabplugins/filter_unsharp/filter_unsharp.cpp
@@ -180,7 +180,7 @@ int FilterUnsharp::getPreConditions(QAction *a) const
   {
 			case FP_VERTEX_QUALITY_SMOOTHING:
 			case FP_UNSHARP_QUALITY:
-					return MeshFilterInterface::FP_Face | MeshFilterInterface::FP_VertexQuality;
+          return MeshModel::MM_FACENUMBER | MeshModel::MM_VERTQUALITY;
   		case FP_SD_LAPLACIAN_SMOOTH:
 			case FP_HC_LAPLACIAN_SMOOTH:
 			case FP_LAPLACIAN_SMOOTH:
@@ -199,13 +199,13 @@ int FilterUnsharp::getPreConditions(QAction *a) const
 			case FP_RECOMPUTE_VERTEX_NORMAL_ANGLE :
 			case FP_FACE_NORMAL_NORMALIZE:	  
 			case FP_CREASE_CUT:
-					return MeshFilterInterface::FP_Face;
+          return MeshModel::MM_FACENUMBER;
 			case FP_UNSHARP_VERTEX_COLOR:	     
-					return MeshFilterInterface::FP_Face | MeshFilterInterface::FP_VertexColor;
+          return MeshModel::MM_FACENUMBER | MeshModel::MM_VERTCOLOR;
 
-			case FP_VERTEX_NORMAL_NORMALIZE:	  return MeshFilterInterface::FP_Generic;
+      case FP_VERTEX_NORMAL_NORMALIZE:	  return MeshModel::MM_NONE;
 					
-    default : assert(0); return MeshFilterInterface::FP_Generic;
+    default : assert(0); return MeshModel::MM_NONE;
   }
 }