// Selects a new edge filter
 public void SetEdgeFilter(IBitmapFilter _edgeFilter)
 {
     edgeFilter = _edgeFilter ?? new NoopFilter("");
     ApplyOnPreview();
     CheckEditorState();
 }
 // Selects a new pixel filter
 public void SetPixelFilter(IBitmapFilter _pixelFilter)
 {
     pixelFilter = _pixelFilter ?? new NoopFilter("");
     ApplyOnPreview();
     CheckEditorState();
 }