pad + mvwaddch position problem

[fpga]

[CODE]
#include <curses.h> 
/* 
run this code as is, noting that all 'sets' print out correctly with their
right edges aligned at x=15. 

Then change PROBLEM's value to 1 and re-run. 

Why does changing b2's 'capacity' to 9 cause it to start printing out 
at a position other than x=15? 

If I make b2's capacity 8 or 10 I don't get a problem. 
    
Any help in explaining the right shift and how to stop it would be most 
appreciated. 
Best regards 
*/ 

#define PROBLEM 0    

//============================================= 
class SetupPad { 
   public: 
      WINDOW * ptr; //ie pPad 

      SetupPad(); 
      ~SetupPad() { delwin(ptr); endwin(); } 
      void linesCols(); 
}; 

SetupPad::SetupPad() 
{ 
   initscr();  
   curs_set(0); 
}; 

void SetupPad::linesCols() 
{ 
   ptr = newpad(LINES-1,COLS-1); 
} 
//============================================= 
class Set 
{ 
   public: 
   int x,y,cap; 
   Set(int nx,int ny, int ncap) : x(nx),y(ny),cap(ncap) {} 
   ~Set(){}    
}; 
//============================================= 
void drawQ(Set * pS,WINDOW * pWin) 
{ 
   int x=pS->x; 
   int y=pS->y; 
   char sym = '.'; 
   for (int j=0;j<pS->cap;j++) 
      mvwaddch(pWin, y, x--, sym); 
} 

void updtScn(SetupPad * pPad) 
{ 
   prefresh(pPad->ptr,0,0,0,0,LINES-1,COLS-1); 
      doupdate(); 
} 

int main() 
{ 
   SetupPad pad; 
   pad.linesCols(); 
   Set b1(15,1,13); 
   Set m1(15,2,10); 
   Set m2(15,3,10); 

#if PROBLEM 
   Set b2(15,4,9); 
#else 
   Set b2(15,4,10);   //works with 8 too! 
#endif 
                         
   drawQ(&b1,pad.ptr); 
   drawQ(&m1,pad.ptr); 
   drawQ(&m2,pad.ptr); 
   drawQ(&b2,pad.ptr); 
   updtScn(&pad); 
   for (int i=0;i<1000000000;i++); //delay so you can see it 
   return 0; 
} 

[/CODE]
-- 
View this message in context: 
http://www.nabble.com/pad-%2B-mvwaddch-position-problem-tf2257874.html#a6262982
Sent from the Gnu - Ncurses forum at Nabble.com.