~ برمجة رسام بلغة السي في بيئة الجرافيك ~

#include <dos.h>
#define MiddleX 159 // 320*200 => X = 320/2 - 1 => X = 159
#define MiddleY 99 // Y = 200/2 - 1 => Y = 99

#define DRAW_PIXEL 0xC // Function for drawing a pixel on screen
#define DELETE_POINT 0x0 // Black Color for Deleting a point(pixel)
#define GREEN_COLOR 0x2 // Color of Pixel
#define PAGE_NUMBER 0x1 // one page no more :)
#define COLUMN MiddleX // Center Screen
#define ROW MiddleY // Center Screen
#define GETCHAR 0x0
#define SET_VIDEO_MODE 0x0
#define VGA_MODE 0x13 // (320*200) 256 color Mode
#define BIOS_INT 0x10 // int 10h
#define KEYBOARD_INT 0x16 // int 16h
#define UP 56 // '8'
#define DOWN 50 // '2'
#define LEFT 52 // '4'
#define RIGHT 54 // '6'
#define DELETE 0x0D // 'ENTER'
#define EXIT 0x20 // int 20h
#define ESC 0x1B //'ESC'
#define GOTO_UP 53 // '5'
#define GOTO_DOWN 48 // '0'
#define GOTO_LEFT 0x2D // '-'
#define GOTO_RIGHT 0x2B // '+'
#define TEXT_MODE 0x03

union REGS IN;
union REGS OUT;


void main(){
IN.h.ah = SET_VIDEO_MODE;
IN.h.al = VGA_MODE;
int86(BIOS_INT,&IN,&OUT);

IN.h.ah = DRAW_PIXEL;
IN.h.al = GREEN_COLOR;
IN.x.bx = PAGE_NUMBER;
IN.x.cx = COLUMN;
IN.x.dx = ROW;
int86(BIOS_INT,&IN,&OUT);

get:
IN.h.ah = GETCHAR;
int86(KEYBOARD_INT,&IN,&OUT);
switch(OUT.h.al){
case UP :
IN.x.dx-=1; // dec dx => dx--
goto DRAW;
break;

case DOWN:
IN.x.dx+=1; // inc dx => dx++
goto DRAW;
break;

case LEFT :
IN.x.cx-=1; // dec cx => cx--
goto DRAW;
break;

case RIGHT:
IN.x.cx+=1; // inc cx => cx++
goto DRAW;
break;

case GOTO_UP:
IN.x.dx-=1; // dec dx => dx--
goto DELTE_A_PIXEL;
break;

case GOTO_DOWN:
IN.x.dx+=1; // inc dx => dx++
goto DELTE_A_PIXEL;
break;

case GOTO_LEFT:
IN.x.cx-=1; // dec cx => cx--
goto DELTE_A_PIXEL;
break;

case GOTO_RIGHT:
IN.x.cx+=1; // inc cx => cx++
goto DELTE_A_PIXEL;
break;

case DELETE:
IN.h.ah = DRAW_PIXEL;
IN.h.al = DELETE_POINT;
int86(BIOS_INT,&IN,&OUT);
goto get;
break;

case ESC:
IN.x.ax = TEXT_MODE;
int86(BIOS_INT,&IN,&OUT);
int86(EXIT,&IN,&OUT);
break;

default:
goto get;
break;
}
DRAW:
IN.h.ah = DRAW_PIXEL;
IN.h.al = GREEN_COLOR;
int86(BIOS_INT,&IN,&OUT);
goto get;

DELTE_A_PIXEL:
IN.h.ah = DRAW_PIXEL;
IN.h.al = DELETE_POINT;
int86(BIOS_INT,&IN,&OUT);
goto get;
}