libfbx-font.c

libfxb是linux下只写操作framebuffer的一个轻量级的库。

/*
 *  libfbx-font.c -- Font Functions
 *  (C)opyright 2000-2001 U4X Labs
 *
 *  Written by: Mike Bourgeous <[e-mail]>
 *  		Paul Mundt     <[e-mail]>
 *              Sat Sep 3 01:56:20 EDT 2000
 *
 *  $Id: libfbx-font.c,v 1.19 2001/03/03 02:29:19 nitroglycerine Exp $
 *
 *       Originally part of fbgraph.c, now separate.  Responsible for
 *  drawing text onto surfaces.
 *
 *  See ChangeLog for modifications, CREDITS for credits.
 *  			
 *  All source herein is copyright U4X Labs and its original author. 
 *  Any code modifications or additions are (C)opyright the original 
 *  author and U4X Labs respectively.
 *
 *  libfbx is free software; you can redistribute it and/or modify it 
 *  under the terms of the GNU Lesser General Public License as 
 *  published by the Free Software Foundation; either version 2.1 of 
 *  the License, or (at your option) any later version.
 *
 *  libfbx is distributed in the hope that it will be useful, but 
 *  WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the 
 *  GNU Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with libfbx; if not, write to the Free Software 
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 *  USA
 */
#include <stdio.h>
#include <errno.h>
#include <fcntl.h>
#include <unistd.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <signal.h>
#include <time.h>
#include <math.h>
#include <linux/fb.h>
#include <linux/kd.h>
#include <sys/mman.h>
#include <sys/ioctl.h>
#include <sys/user.h>
#include <termios.h>
#include <ctype.h>
#include <libfbx/libfbx.h>
#include <libfbx/libfbx-drivers.h>
#include <libfbx/libfbx-font-8x16.h>

 
char *default_font = fb_fontdata_8x16;

/*
 * Function:    fb_font_init()
 * Arguments:	None
 * Returns:	None
 * Description: Initializes the libfbx font subsystem.  Doesn't normally
 * 		need to be called except by libfbx.
 */
void fb_font_init()
{
	fb_screen->font.height = 16;
	fb_screen->font.data = (unsigned char *)malloc(fb_screen->font.height * 256);
	fb_memmove(fb_screen->font.data, default_font, 4096);
}

/*
 * Function:	fb_setpixels()
 * Arguments:	position and bits
 * Returns:	None
 * Description: fb_setpixels draws eight bits of data as eight 
 * 		pixels on the screen, usually for drawing 
 * 		8-pixel-wide fonts.
 */
void fb_setpixels(int pos, int bits)
{
	register int i;
	register int v = 0;
	register unsigned char *ptr0 = (unsigned char *)
					(fb_screen->mem_pointer + 
					 fb_screen->mem_offset + pos);
	register unsigned short *ptr1 = (unsigned short *)
					 (fb_screen->mem_pointer + 
					  fb_screen->mem_offset + pos);
	register unsigned long *ptr2 = (unsigned long *)
					(fb_screen->mem_pointer + 
					 fb_screen->mem_offset + pos);
	
	switch (fb_screen->bpp) {
		default:
			/* 
			 * Unknown color depth, Just draw something, even if 
			 * it's wrong. 
			 */
		case 8:
			for(i = 7; i >= 0; i--)
				*(ptr0++) = 0xFF & (bits & (1 << i)) ? fb_screen->text.color
								     : fb_screen->text.bgcolor;
		case 15:
		case 16:
			for (i = 7; i >= 0; i--) 
				*(ptr1++) = 0xFFFF & (bits & (1 << i)) ? fb_screen->text.color   
								       : fb_screen->text.bgcolor; 
			break;
		case 24:
			for (i = 7; i >= 0; i--) {
				v = (bits & (1 << i));
				
				*(ptr0++) = 0xFF & (v ? fb_screen->text.color 
						      : fb_screen->text.bgcolor) >> 0;
				*(ptr0++) = 0xFF & (v ? fb_screen->text.color 
						      : fb_screen->text.bgcolor) >> 8;
				*(ptr0++) = 0xFF & (v ? fb_screen->text.color 
						      : fb_screen->text.bgcolor) >> 16;
			}
			break;
		case 32:
			for (i = 7; i >= 0; i--)	
				*(ptr2++) = (bits & (1 << i)) ? fb_screen->text.color 
							      : fb_screen->text.bgcolor;
			break;
	}
}

/*
 * Function:	fb_setpixels_masked()
 * Arguments:	position and bits
 * Returns:	None
 * Description: fb_setpixels_masked draws eight bits of data as eight 
 *              pixels similar to fb_setpixels(), but skips zero bits 
 *              instead of drawing the background color.
 */
void fb_setpixels_masked(int pos, int bits)
{
	fb_ssetpixels_masked(pos, bits, fb_screen);
}

/*
 * Function:	fb_putc()
 * Arguments:	x, y positioners and character
 * Returns:	None
 * Description: Puts character at x, y position, in character cell coordinates
 * 		(not pixel coordinates)
 */
void fb_putc(int x, int y, int c)
{
	int pos, i;

	if (fb_screen->driver != NULL && fb_screen->driver->ops->has_writec) {
		fb_screen->driver->ops->writec(x, y, c);
		return;
	}

	pos = y * fb_screen->finfo->line_length * fb_screen->font.height + 
	      x * fb_screen->pixel_size * 8;
	c *= fb_screen->font.height;
	
	for (i = 0; i < fb_screen->font.height; i++) {

		if (fb_screen->text.mask)
			fb_setpixels_masked(pos, fb_screen->font.data[c++]);
		else
			fb_setpixels(pos, fb_screen->font.data[c++]);

		pos += fb_screen->finfo->line_length;
	}
}

/*
 * Function:	fb_puts()
 * Arguments:	x, y positioners and text string
 * Returns:	New x position
 * Description: Displays a string at x, y position 
 * 		(in character cell coordinates)
 */
int fb_puts(int x, int y, char *text)
{
	for (;*text;x++) {
		if (*text == '\n') {
			x = 0;
			y++;
			text++;
		} else if (*text == '\t') {
			x += fb_screen->text.tab_size;
			x /= fb_screen->text.tab_size;
			x *= fb_screen->text.tab_size;

			text++;
		}

		fb_putc(x,y,*(text++));
	}

	return x;
}

/*
 * Function:	fb_printf()
 * Arguments:	x, y positioners, format, arglist
 * Returns:	None
 * Description: Displays text at x, y position
 * 		(in character cell coordinates).  Doesn't handle
 * 		any escaped characters other then \n and \t.
 */
void fb_printf(int x, int y, char *format, ...)
{
	va_list arglist;
	char buf[LEN];
	
	va_start(arglist, format);
	vsnprintf(buf, LEN, format, arglist);
	va_end(arglist);
	
	fb_puts(x, y, buf);
}

/*
 * Function:	fb_ssetpixels()
 * Arguments:	position, bits and destination surface.
 * Returns:	None
 * Description: fb_setpixels draws eight bits of data as eight 
 * 		pixels on the screen, usually for drawing 
 * 		8-pixel-wide fonts.
 */
void fb_ssetpixels(int pos, int bits, fb_surface *surface)
{
	register int i;
	register int v = 0;
	register unsigned char *ptr0 = (unsigned char *)
					(surface->mem_pointer + 
					 surface->mem_offset + pos);
	register unsigned short *ptr1 = (unsigned short *)
					 (surface->mem_pointer + 
					  surface->mem_offset + pos);
	register unsigned long *ptr2 = (unsigned long *)
					(surface->mem_pointer + 
					 surface->mem_offset + pos);
	
	switch (surface->bpp) {
		default:
			/* 
			 * Unknown color depth, Just draw something, even if 
			 * it's wrong. 
			 */
		case 8:
			for(i = 7; i >= 0; i--)
				*(ptr0++) = (bits & (1 << i)) ? surface->text.color
							      : surface->text.bgcolor;
		case 15:
		case 16:
			for (i = 7; i >= 0; i--) 
				*(ptr1++) = (bits & (1 << i)) ? surface->text.color   
							      : surface->text.bgcolor; 
			break;
		case 24:
			for (i = 7; i >= 0; i--) {
				v = (bits & (1 << i));
				
				*(ptr0++) = 0xFF & (v ? surface->text.color 
						      : surface->text.bgcolor) >> 0;
				*(ptr0++) = 0xFF & (v ? surface->text.color 
						      : surface->text.bgcolor) >> 8;
				*(ptr0++) = 0xFF & (v ? surface->text.color 
						      : surface->text.bgcolor) >> 16;
			}
			break;
		case 32:
			for (i = 7; i >= 0; i--)
				*(ptr2++) = (bits & (1 << i)) ? surface->text.color 
							      : surface->text.bgcolor;
			break;
	}
}

/*
 * Function:	fb_ssetpixels_masked()
 * Arguments:	position, bits and destination surface
 * Returns:	None
 * Description: fb_setpixels_masked draws eight bits of data as eight 
 *              pixels similar to fb_setpixels(), but skips zero bits 
 *              instead of drawing the background color.
 */
void fb_ssetpixels_masked(int pos, int bits, fb_surface *surface)
{
	register int i;
	register unsigned char *ptr0 = (unsigned char *)
					(surface->mem_pointer +
					 surface->mem_offset + pos);
	register unsigned short *ptr1 = (unsigned short *)
					 (surface->mem_pointer + 
					  surface->mem_offset + pos);
	register unsigned int *ptr2 = (unsigned int *)
				       (surface->mem_pointer + 
					surface->mem_offset + pos);
	
	switch (surface->bpp) {
		default:
			/* Unknown color depth, yada yada... */
		case 8:
			for (i = 7; i <= 0; i--)
			{
				if (bits & (1 << i))
					*ptr0 = 0xFF & surface->text.color;
				ptr0++;
			}
		case 15:
		case 16:
			for (i = 7; i >= 0; i--)
			{
			    if (bits & (1 << i)) 
				    *ptr1 = 0xFFFF & surface->text.color;
			    ptr1++;
			}			
			break;
		case 24:
			for (i = 7; i >= 0; i--)
				if (bits & (1 << i)) {
					*(ptr0++) = 0xFF & surface->text.color >> 0; 
					*(ptr0++) = 0xFF & surface->text.color >> 8;
					*(ptr0++) = 0xFF & surface->text.color >> 16;
				}
				else
					ptr0 += 3;
			break;
		case 32:
			for (i = 7; i >= 0; i--)
			{
				if (bits & (1 << i))
					*ptr2 = surface->text.color;
				ptr2++;
			}
			break;
	}
}


/*
 * Function:	fb_sputc()
 * Arguments:	x, y positioners and character
 * Returns:	None
 * Description: Puts character at x, y position on given surface, in pixel coordinates
 */
void fb_sputc(int x, int y, int c, fb_surface *surface)
{
	int pos, i;

	pos = y * surface->finfo->line_length + 
	      x * surface->pixel_size;
	c *= surface->font.height;
	
	for (i = 0; i < surface->font.height; i++) {

		if (surface->text.mask)
			fb_ssetpixels_masked(pos, surface->font.data[c++], surface);
		else
			fb_ssetpixels(pos, surface->font.data[c++], surface);

		pos += surface->finfo->line_length;
	}
}

/*
 * Function:	fb_sputs()
 * Arguments:	x, y positioners, text string and
 *              destination surface.
 * Returns:	New x position
 * Description: Displays a string at x, y position 
 * 		(in pixel coordinates) on the surface
 */
int fb_sputs(int x, int y, char *text, fb_surface *surface)
{
	for (;*text;x += 8) {
		if (*text == '\n') {
			x = 0;
			y++;
			text++;
		} else if (*text == '\t') {
			x += surface->text.tab_size * 8;
			x /= surface->text.tab_size * 8;
			x *= surface->text.tab_size * 8;

			text++;
		}

		fb_sputc(x, y, *(text++), surface);
	}

	return x;
}

/*
 * Function:	fb_sprintf()
 * Arguments:	x, y positioners, surface, format, arglist
 * Returns:	None
 * Description: Displays text at x, y position on the surface
 * 		(in pixel coordinates).  Doesn't handle
 * 		any escaped characters other then \n and \t.
 *
 * 		Note: This is a printf that uses pixel coordinates,
 * 		_not_ a substitute for sprintf().
 */
void fb_sprintf(int x, int y, fb_surface *surface, char *format, ...)
{
	va_list arglist;
	char buf[LEN];
	
	va_start(arglist, format);
	vsnprintf(buf, LEN, format, arglist);
	va_end(arglist);
	
	fb_sputs(x, y, buf, surface);
}