A simple graphics rectangle? My coordinates are wrong

[StephenG1CMZ]

Thanks for your insights guys...
This version seems much clearer.
One known bug for me to look into in this code if it becomes necessary:
If border width is changed to 0 a border still appears.

Code:



 LOCAL Y0:=0;
 LOCAL BWIDTH:=8; //FRAME OR BORDER
 //KNOWN BUG:A WIDTH OF 0 STILL GIVES A BORDER
 
 LOCAL XLEN:=255; //255;
 LOCAL YLEN:=192; //192; //OR 175 MAIN AREA
 //INNER RECT IS XLEN*YLEN
 LOCAL BORDERU,BORDERD,BORDERL,BORDERR,SCRN;
 LOCAL COLRB:=RGB(0,0,#CDh);
 LOCAL COLRS:=RGB(0,#CDh,0);

 INITS()
 BEGIN
  BORDERU:={0,Y0,             XLEN+2*BWIDTH-1,Y0+BWIDTH-1};
  BORDERD:={0,Y0+BWIDTH+YLEN, XLEN+2*BWIDTH-1,Y0+YLEN+2*BWIDTH-1};
  BORDERL:={0,Y0+BWIDTH,      BWIDTH-1,Y0+YLEN+BWIDTH-1};
  BORDERR:={XLEN+BWIDTH,Y0,   XLEN+2*BWIDTH-1,Y0+YLEN+2*BWIDTH-1};
  SCRN:=   {BWIDTH,Y0+BWIDTH, XLEN+BWIDTH-1,Y0+YLEN+BWIDTH-1,COLRS};
 END;

 DRAW_BORDER()
 BEGIN
  RECT_P(BORDERU(1),BORDERU(2),BORDERU(3),BORDERU(4),COLRB);
  RECT_P(BORDERR(1),BORDERR(2),BORDERR(3),BORDERR(4),COLRB);
  RECT_P(BORDERD(1),BORDERD(2),BORDERD(3),BORDERD(4),COLRB);
  RECT_P(BORDERL(1),BORDERL(2),BORDERL(3),BORDERL(4),COLRB);
  WAIT;
 END;

 DRAW_SCREEN()
 BEGIN
  RECT_P(SCRN(1),SCRN(2),SCRN(3),SCRN(4),COLRS);
 END;

 
 EXPORT BORDER()
 BEGIN
  RECT_P();
  INITS();
  DRAW_BORDER();
  DRAW_SCREEN();
  FREEZE; 
 END;