/* GNUPLOT - emxvga.trm */
/*
 * Copyright (C) 1993
 *
 * Permission to use, copy, and distribute this software and its
 * documentation for any purpose with or without fee is hereby granted, 
 * provided that the above copyright notice appear in all copies and 
 * that both that copyright notice and this permission notice appear 
 * in supporting documentation.
 *
 * Permission to modify the software is granted, but not the right to
 * distribute the modified code.  Modifications are to be distributed 
 * as patches to released version.
 *
 * This software  is provided "as is" without express or implied warranty.
 *
 * This file is included by ../term.c.
 *
 * This terminal driver supports:
 *  vgal
 *  vesa
 *
 * AUTHORS
 *  Russell Lang
 *
 * send your comments or suggestions to (info-gnuplot@dartmouth.edu).
 *
 */

/* VGA driver using EMX/GCC for DOS */

void EMXVGA_init __P((void));
void EMXVGA_graphics __P((void));
void EMXVGA_text __P((void));
void EMXVGA_reset __P((void));
void EMXVESA_options __P((void));
void EMXVESA_init __P((void));
void EMXVESA_graphics __P((void));
void EMXVESA_text __P((void));
void EMXVESA_reset __P((void));
void EMXVGA_linetype __P((int linetype));
void EMXVGA_move __P((unsigned int x, unsigned int y));
void EMXVGA_vector __P((unsigned int x, unsigned int y));
int EMXVGA_text_angle __P((int ang));
void EMXVGA_putc __P((unsigned int x, unsigned int y, char c, int angle));
void EMXVGA_put_text __P((unsigned int x, unsigned int y, char *str));

#include <graph.h>
#include <conio.h>
#include <dos.h>

int emx_startx, emx_starty;
int emx_xlast, emx_ylast;
int emx_color;
int emx_angle;
int emx_vmode = 0;
#ifdef EMXVESA
int emx_vesamode = G640x480x256;
#endif

#define EMXVGA_XMAX 640
#define EMXVGA_YMAX 480

#define EMXVGA_XLAST (EMXVGA_XMAX - 1)
#define EMXVGA_YLAST (EMXVGA_YMAX - 1)

#define EMXVGA_VCHAR FNT5X9_VCHAR
#define EMXVGA_HCHAR FNT5X9_HCHAR
#define EMXVGA_VTIC 4
#define EMXVGA_HTIC 4

#define EMXNUMCOLOR 15
static int emx_colors[EMXNUMCOLOR] = {7,8,2,3,4,5,9,14,12,15,13,10,11,1,6};


void EMXVGA_init()
{
union REGS r;
	r.h.ah = 0x0f;
	_int86(0x10, &r, &r);
	emx_vmode = r.h.al;	/* save old video mode */
	/* Get the screen size: */
	if (!g_mode(G_MODE_VGA_L))
		int_error("Couldn't select graphics mode",NO_CARET);
	emx_xlast = g_xsize - 1;
    	term->xmax = emx_xlast + 1;
	emx_ylast = g_ysize - 1;
    	term->ymax = emx_ylast + 1;
	g_mode(G_MODE_OFF);
}

void EMXVGA_graphics()
{
/* don't use g_mode() here - gmode(G_MODE_OFF) doesn't clean up */
union REGS r;
	r.h.ah = 0x00;
	r.h.al = 19;		/* VGA 320x200x256 mode */
	_int86(0x10, &r, &r);
}

void EMXVGA_text()
{
/* don't use g_mode() here - gmode(G_MODE_OFF) doesn't clean up */
union REGS r;
int ch;
	ch = getch();
	r.h.ah = 0x00;
	r.h.al = emx_vmode;	/* old video mode */
	_int86(0x10, &r, &r);
	if (ch == 3)
		int_error("Interrupt",NO_CARET);
}

void EMXVGA_reset()
{
}

#ifdef EMXVESA
/* untested */
void EMXVESA_options()
{
	if (!END_OF_COMMAND) {
		if (almost_equals(c_token,"d$efault")) {
			emx_vesamode = G640x480x256;
			c_token++;
		}
	}

	if (!END_OF_COMMAND) {
		/* We have a vesa mode specified */
		struct value a;
		emx_vesamode = (int)real(const_express(&a));
	}

	sprintf(term_options,"%d",emx_vesamode);
}

void EMXVESA_init()
{
	if (!g_mode(emx_vesamode))
		int_error("Couldn't select graphics mode",NO_CARET);
	emx_xlast = g_xsize - 1;
    	term->xmax = emx_xlast + 1;
	emx_ylast = g_ysize - 1;
    	term->ymax = emx_ylast + 1;
	g_mode(GTEXT);
}

void EMXVESA_graphics()
{
	g_mode(emx_vesamode);
}

void EMXVESA_text()
{
int ch;
	ch = getch();
	g_mode(GTEXT);
	if (ch == 3)
		int_error("Interrupt",NO_CARET);
}

void EMXVESA_reset()
{
}
#endif


void EMXVGA_linetype(linetype)
int linetype;
{
	if (linetype >= 13)
		linetype %= 13;
	emx_color = emx_colors[linetype+2];
}

void EMXVGA_move(x,y)
unsigned int x,y;
{
	emx_startx = x;
	emx_starty = y;
}


void EMXVGA_vector(x,y)
unsigned int x,y;
{
	g_line(emx_startx,emx_ylast-emx_starty,x,emx_ylast-y,emx_color);
	emx_startx = x;
	emx_starty = y;
}


int EMXVGA_text_angle(ang)
int ang;
{
	emx_angle=ang;
	return TRUE;
}


void EMXVGA_putc(x,y,c,angle)
unsigned int x,y;
char c;
int angle;
{
int i,j,k;
unsigned int pixelon;
	i = (int)(c) - 32;
	for (j=0; j<FNT5X9_VBITS; j++) {
		for (k=0; k<FNT5X9_HBITS; k++) {
			pixelon = (((unsigned int)(fnt5x9[i][j])) >> k & 1);
			if (pixelon) {
				switch(angle) {
					case 0 : g_set(x+k,y-j,emx_color);
							break;
					case 1 : g_set(x-j,y-k,emx_color);
							break;
				}
			}
		}
	}
}


void EMXVGA_put_text(x,y,str)
unsigned int x, y;
char *str;
{
int i;
	switch(emx_angle) {
		case 0 : y -= EMXVGA_VCHAR/2;
				break;
		case 1 : x += EMXVGA_VCHAR/2;
				break;
	}
	for (i=0;str[i];i++) {
		EMXVGA_putc(x,emx_ylast-y,str[i],emx_angle);
		switch(emx_angle) {
			case 0 : x+=EMXVGA_HCHAR ;
					break;
			case 1 : y+=EMXVGA_HCHAR ;
					break;
		}
	}
}