code.delx.au - gnu-emacs/blob - test/manual/etags/cp-src/screen.cpp

   1 /* ======================================================================= */
   2 /*                                SCREEN.CPP                               */
   3 /* ======================================================================= */
   4
   5 #include "stdio.h"
   6 #include "stdlib.h"
   7 #include "dos.h"
   8
   9 #include "screen.h"
  10
  11 /* ----------------------------------------------------------------------- */
  12 /*              Cursor Position and Screen Buffering Functions             */
  13 /* ----------------------------------------------------------------------- */
  14
  15 unsigned char cursor_x, cursor_y;
  16 static union REGS regs;
  17
  18 void goto_xy(unsigned char x, unsigned char y)
  19     {
  20     regs.h.ah = 2;
  21     regs.h.bh = 0;
  22     regs.h.dh = y;
  23     regs.h.dl = x;
  24     int86(0x10, &regs, &regs);
  25     }
  26
  27 void hide_cursor(void)
  28     {
  29     goto_xy(0, NUM_ROWS);
  30     }
  31
  32 void cursor_position(void)
  33     {
  34     regs.h.ah = 3;
  35     regs.h.bh = 0;
  36     int86(0x10, &regs, &regs);
  37     cursor_x = regs.h.dl;
  38     cursor_y = regs.h.dh;
  39     }
  40
  41 void clear_screen(void)
  42     {
  43     unsigned int i, j;
  44     char far *p;
  45
  46     p = SCREEN_START;
  47     for (i = 0; i < NUM_ROWS; i++)
  48         for (j = 0; j < 80; j++)
  49             {
  50             *p++ = ' ';
  51             *p++ = LIGHTGRAY;
  52             }
  53     }
  54
  55 void write_xyc(int x, int y, char c)
  56     {
  57     char far *p;
  58
  59     p = SCREEN_FP(x, y);
  60     *p++ = c;
  61     *p = LIGHTGRAY;
  62     }