#if defined(__TURBOC__)extern "C" unsigned char inportb(int port_id);extern "C" void outportb(int portid, unsigned char value);#define _PORT_DEFS#endif#include <dos.h>#include <conio.h>#if defined(__EMX__)#include <sys/hw.h>#define port_out(value,port) _outp32(port,value)#define port_in(port)  _inp32(port)#elif defined(__TURBOC__) || defined(__GNUG__)#define port_out(value,port) outportb(port,value)#define port_in(port)  inportb(port)#else#define port_out(value,port) outp(port,value)#define port_in(port)  inp(port)#endif#if defined (__ZTC__) || defined(__TURBOC__)typedef unsigned char far* VIDEO_PTR;#elsetypedef unsigned char* VIDEO_PTR;#endif/*  * basic graphics routines in VGA mode 640x480x16 * (part of this code is based on "VGAlib" by Tommy Frandsen) */static VIDEO_PTR VIDEO;static int LINE_BYTES;static int VGA_WIDTH;static int VGA_MAX_X;static int VGA_HEIGHT;static int VGA_MAX_Y;static int VGA_DEPTH;#define FONT_SIZE  0x2000/* VGA index register ports */#define CRT_IC  0x3D4   /* CRT Controller Index - color emulation */#define CRT_IM  0x3B4   /* CRT Controller Index - mono emulation */#define ATT_IW  0x3C0   /* Attribute Controller Index & Data Write Register */#define GRA_I   0x3CE   /* Graphics Controller Index */#define SEQ_I   0x3C4   /* Sequencer Index */#define PEL_IW  0x3C8   /* PEL Write Index */#define PEL_IR  0x3C7   /* PEL Read Index *//* VGA data register ports */#define CRT_DC  0x3D5   /* CRT Controller Data Register - color emulation */#define CRT_DM  0x3B5   /* CRT Controller Data Register - mono emulation */#define ATT_R   0x3C1   /* Attribute Controller Data Read Register */#define GRA_D   0x3CF   /* Graphics Controller Data Register */#define SEQ_D   0x3C5   /* Sequencer Data Register */#define MIS_R   0x3CC   /* Misc Output Read Register */#define MIS_W   0x3C2   /* Misc Output Write Register */#define IS1_RC  0x3DA   /* Input Status Register 1 - color emulation */#define IS1_RM  0x3BA   /* Input Status Register 1 - mono emulation */#define PEL_D   0x3C9   /* PEL Data Register *//* VGA indexes max counts */#define CRT_C   24      /* 24 CRT Controller Registers */#define ATT_C   21      /* 21 Attribute Controller Registers */#define GRA_C   9       /* 9  Graphics Controller Registers */#define SEQ_C   5       /* 5  Sequencer Registers */#define MIS_C   1       /* 1  Misc Output Register *//* VGA registers saving indexes */#define CRT     0               /* CRT Controller Registers start */#define ATT     CRT+CRT_C       /* Attribute Controller Registers start */#define GRA     ATT+ATT_C       /* Graphics Controller Registers start */#define SEQ     GRA+GRA_C       /* Sequencer Registers */#define MIS     SEQ+SEQ_C       /* General Registers */#define END     MIS+MIS_C       /* last *//* variables used to shift between monchrome and color emulation */static int CRT_I;		/* current CRT index register address */static int CRT_D;		/* current CRT data register address */static int IS1_R;		/* current input status register address */static int color_text;		/* true if color text emulation *//* BIOS mode 12h - 640x480x16 */static char g640x480x16_regs[60] = {  0x5F,0x4F,0x50,0x82,0x54,0x80,0x0B,0x3E,0x00,0x40,0x00,0x00,  0x00,0x00,0x00,0x00,0xEA,0x8C,0xDF,0x28,0x00,0xE7,0x04,0xE3,  0x00,0x01,0x02,0x03,0x04,0x05,0x06,0x07,0x08,0x09,0x0A,0x0B,  0x0C,0x0D,0x0E,0x0F,0x01,0x00,0x0F,0x00,0x00,  0x00,0x0F,0x00,0x20,0x00,0x00,0x05,0x0F,0xFF,  0x03,0x01,0x0F,0x00,0x06,  0xE3};static char text_regs[60];   /* VGA registers for saved text mode *//* saved text mode palette values */static char text_red[256];static char text_green[256];static char text_blue[256];static int initialized = 0;static char font_buf1[FONT_SIZE];  /* saved font data - plane 2 */static char font_buf2[FONT_SIZE];  /* saved font data - plane 3 */static void set_regs(char regs[]){    int i;    /* disable video */    port_in(IS1_R);	    port_out(0x00, ATT_IW);    /* update misc output register */    port_out(regs[MIS], MIS_W);    /* synchronous reset on */    port_out(0x00,SEQ_I);    port_out(0x01,SEQ_D);	    /* write sequencer registers */    for (i = 1; i < SEQ_C; i++) {	port_out(i, SEQ_I);	port_out(regs[SEQ+i], SEQ_D);    }    /* synchronous reset off */    port_out(0x00, SEQ_I);    port_out(0x03, SEQ_D);	    /* deprotect CRT registers 0-7 */    port_out(0x11, CRT_I);		    port_out(port_in(CRT_D)&0x7F, CRT_D);    /* write CRT registers */    for (i = 0; i < CRT_C; i++) {	port_out(i, CRT_I);	port_out(regs[CRT+i], CRT_D);    }    /* write graphics controller registers */    for (i = 0; i < GRA_C; i++) {	port_out(i, GRA_I);	port_out(regs[GRA+i], GRA_D);    }    /* write attribute controller registers */    for (i = 0; i < ATT_C; i++) {	port_in(IS1_R);   /* reset flip-flop */	port_out(i, ATT_IW);	port_out(regs[ATT+i],ATT_IW);    }}static void vga_initialize(){    int  i, j;    int mem_fd = -1;  /* /dev/mem file descriptor		     */    if (initialized) return;    initialized = 1;#if defined(__EMX__)    _portaccess(0x300,0x3FF);    VIDEO = (VIDEO_PTR)_memaccess(0xa0000,0xaffff,1);#elif defined(__GNUC__)    VIDEO = (VIDEO_PTR)0xd0000000;#elif defined(__ZTC__)    VIDEO = (VIDEO_PTR)_x386_mk_protected_ptr(0xa0000);#elif defined(__WATCOMC__)    VIDEO = (VIDEO_PTR)0xa0000;#else    VIDEO = (VIDEO_PTR)MK_FP(0xa000,0);#endif    /* color or monochrome text emulation? */    color_text = port_in(MIS_R)&0x01;    /* chose registers for color/monochrome emulation */    if (color_text) {	CRT_I = CRT_IC;	CRT_D = CRT_DC;	IS1_R = IS1_RC;    } else {	CRT_I = CRT_IM;	CRT_D = CRT_DM;	IS1_R = IS1_RM;    }    /* disable video */    port_in(IS1_R);	    port_out(0x00, ATT_IW);    /* save text mode palette - first select palette index 0 */    port_out(0, PEL_IR);    /* read RGB components - index is autoincremented */    for(i = 0; i < 256; i++) {	for(j = 0; j < 10; j++) ;   /* delay (minimum 240ns) */	text_red[i] = port_in(PEL_D);	for(j = 0; j < 10; j++) ;   /* delay (minimum 240ns) */	text_green[i] = port_in(PEL_D);	for(j = 0; j < 10; j++) ;   /* delay (minimum 240ns) */	text_blue[i] = port_in(PEL_D);    }    /* save text mode VGA registers */    for (i = 0; i < CRT_C; i++) {	 port_out(i, CRT_I);	 text_regs[CRT+i] = port_in(CRT_D);    }    for (i = 0; i < ATT_C; i++) {      	 port_in(IS1_R);         port_out(i, ATT_IW);         text_regs[ATT+i] = port_in(ATT_R);    }    for (i = 0; i < GRA_C; i++) {       	 port_out(i, GRA_I);       	 text_regs[GRA+i] = port_in(GRA_D);    }    for (i = 0; i < SEQ_C; i++) {       	 port_out(i, SEQ_I);       	 text_regs[SEQ+i] = port_in(SEQ_D);    }    text_regs[MIS] = port_in(MIS_R);    /* shift to color emulation */    CRT_I = CRT_IC;    CRT_D = CRT_DC;    IS1_R = IS1_RC;    port_out(port_in(MIS_R)|0x01, MIS_W);    /* save font data - first select a 16 color graphics mode */    set_regs(g640x480x16_regs);    /* save font data in plane 2 */    port_out(0x04, GRA_I);    port_out(0x02, GRA_D);    for(i = 0; i < FONT_SIZE; i++) font_buf1[i] = VIDEO[i];    /* save font data in plane 3 */    port_out(0x04, GRA_I);    port_out(0x03, GRA_D);    for(i = 0; i < FONT_SIZE; i++) font_buf2[i] = VIDEO[i];}void vga_setpal(int index, int red, int green, int blue){    volatile int i;    /* select palette register */    port_out(index, PEL_IW);    /* write RGB components */    for(i = 0; i < 10; i++) ;   /* delay (minimum 240ns) */    port_out(red/4, PEL_D);    for(i = 0; i < 10; i++) ;   /* delay (minimum 240ns) */    port_out(green/4, PEL_D);    for(i = 0; i < 10; i++) ;   /* delay (minimum 240ns) */    port_out(blue/4, PEL_D);}void vga_getpal(int index, int *red, int *green, int *blue){    int i;    /* select palette register */    port_out(index, PEL_IR);    /* read RGB components */    for(i = 0; i < 10; i++) ;   /* delay (minimum 240ns) */    *red = 4*(int) port_in(PEL_D);    for(i = 0; i < 10; i++) ;   /* delay (minimum 240ns) */    *green = 4*(int) port_in(PEL_D);    for(i = 0; i < 10; i++) ;   /* delay (minimum 240ns) */    *blue = 4*(int) port_in(PEL_D);}void vga_clear(int c){  register VIDEO_PTR p;  register VIDEO_PTR last;  /* set color c */  port_out(c, GRA_I );  port_out(0, GRA_D );  /* set mode 0 */  port_out(0x03, GRA_I );  port_out(0, GRA_D );  /* write to all bits */  port_out(0x08, GRA_I );  port_out(0xFF, GRA_D );  last  = VIDEO + VGA_HEIGHT*LINE_BYTES;  for(p = VIDEO; p < last; p++)  *p = 0;}void vga_init(int mode){   // mode = 0: Text, 1: 640x480x16      int i;    vga_initialize();        if (mode == 0)  // TEXT      {         //vga_clear(0);        /* restore font data - first select a 16 color graphics mode */        set_regs(g640x480x16_regs);	/* disable Set/Reset Register */    	port_out(0x01, GRA_I );    	port_out(0x00, GRA_D );        /* restore font data in plane 2 - necessary for all VGA's */    	port_out(0x02, SEQ_I );    	port_out(0x04, SEQ_D );        for(i = 0; i < FONT_SIZE; i++) VIDEO[i] = font_buf1[i];        /* restore font data in plane 3 - necessary for Trident VGA's */    	port_out(0x02, SEQ_I );    	port_out(0x08, SEQ_D );        for(i = 0; i < FONT_SIZE; i++) VIDEO[i] = font_buf2[i];        /* change register adresses if monochrome text mode */        if (!color_text) {            CRT_I = CRT_IM;            CRT_D = CRT_DM;            IS1_R = IS1_RM;            port_out(port_in(MIS_R)&0xFE, MIS_W);        }	/* restore text mode VGA registers */    	set_regs(text_regs);        /* restore saved palette */        for(i = 0; i < 256; i++)            vga_setpal(i, text_red[i], text_green[i], text_blue[i]);        VGA_WIDTH = 80;        VGA_HEIGHT= 25;      }    else // graphics mode      {         /* shift to color emulation */        CRT_I = CRT_IC;        CRT_D = CRT_DC;        IS1_R = IS1_RC;        port_out(port_in(MIS_R)|0x01, MIS_W);