The Fct_Update and Fct_Redraw are use to signal sliceOmatic when you have done something that affect the rest of the program.

 

For example, if you change the value of the TAG_Cur variable (you change the currently selected TAG), some of the tools (like TAG_Lock) need to know about this so that it can be refreshed correctly.  This is done by calling:

          Fct_Update( UPDATE_CUR_TAG ) ;

 

Or, if your module has segmented a region on an image, then it mean that you have modified the TAG values associated with a specific frame.  You then need to tell sliceO that you have updated the TAG values and that these new values need to be redrawn.  You would do this by calling:

          Fct_Update( UPDATE_DISPLAY_TAG, CLASS_MODE_ALL, frame, region ) ;

          Fct_Redraw( REDRAW_DB_OPENGL, CLASS_MODE_ALL, frame, region ) ;