font.c

zgv-5.6,一个Linux系统下的图片浏览器(VGA/SVGA)

/* Zgv v3.1 - GIF, JPEG and PBM/PGM/PPM viewer, for VGA PCs running Linux.
 * Copyright (C) 1993-1998 Russell Marks. See README for license details.
 *
 * font.c - provides a font of sorts for use via svgalib, and
 *		code to use (nicer) BDF fonts converted with bdf2h.
 */


/* all the line-based font stuff is hard-coded and a bit ugly, so you
 * probably won't want much to look at that (hint) :-)
 */

 
#include <stdio.h>
#include <string.h>
#include <vga.h>
#include "zgv.h"
#include "font.h"
#include "fontbmps.h"
#include "rc_config.h"
#include "rcfile.h"

#define TABSIZE  64   /* size of a tab, in pixels */


static int go_through_the_motions=0;
  /* if 1, we don't draw it, just do the width */

static int stop_after_this_x=NO_CLIP_FONT;

static int squish_x=0;


/* the copyright/license for the bitmap fonts says that all
 * copies of the fonts must contain the copyright. Since a copy
 * was embedded in the program above (`fontbmps.h'), we'd
 * best have this:
 */
static char *bitmap_fonts_copyright=
"The bitmap fonts zgv uses are: \
Copyright 1984-1989, 1994 Adobe Systems Incorporated. \
Copyright 1988, 1994 Digital Equipment Corporation.";


/* prototypes */
int vgadrawtext(int x, int y, int siz, char *str);
void fontcircle(int x, int y, int r);
void fontc_l(int x, int y, int r);
void fontc_u(int x, int y, int r);
void fontc_r(int x, int y, int r);
void fontc_left(int x, int y, int r);
void fontc_ul(int x, int y, int r);
void fontc_ur(int x, int y, int r);
void fontc_ll(int x, int y, int r);
void fontc_lr(int x, int y, int r);
int vgatextsize(int sizearg, char *str);
void set_max_text_width(int width);
static int vgadrawtext_bmp(int xpos,int ypos,int siz,char *str);


/* unused dummy routine to stop -Wall complaining about the copyright
 * message not being used.
 */
static void its_too_damn_picky_sometimes()
{
printf(bitmap_fonts_copyright);
}


/* needed for 360x480 mode */
#define vga_drawline(x1,y1,x2,y2) \
	(squish_x?vga_drawline((x1)>>1,y1,(x2)>>1,y2):\
        	  vga_drawline(x1,y1,x2,y2))
#define vga_drawpixel(x1,y1) \
	(squish_x?vga_drawpixel((x1)>>1,y1):\
        	  vga_drawpixel(x1,y1))


/* returns width of text drawn in pixels */
int vgadrawtext(int x,int y,int siz,char *str)
{
int f,a,b,c,s1,s2,s3,s4,s5,s6,gap;

/* needed for both line and bitmap fonts */
squish_x=(vga_getcurrentmode()==G360x480x256);

if(!cfg.linetext || siz==0) return(vgadrawtext_bmp(x,y,siz,str));

/* bold not supported by linetext version, use siz=2 instead */
if(siz==USE_BOLD_FONT) siz=2;

if(squish_x) x*=2;	/* since vga_drawline/pixel will divide by 2 */

b=y;
a=x;
s1=siz; s2=s1<<1; s3=s1+s2; s4=s2<<1; s5=s4+s1; s6=s3<<1;
gap=s1; if(gap==0) gap=1;

for(f=0;f<strlen(str);f++)
  {
  /* s3+s4 is the size that an ellipsis will take up (s3), plus the
   * widest possible letter (M = s4).
   */
  if(a-x>stop_after_this_x-s3-s4)
    {
    int tmp;
    
    /* print an ellipsis... well, three^H^H^H^H^Htwo dots :-) */
    /* blast the width restriction to stop possible infinite recursion */
    tmp=stop_after_this_x;
    set_max_text_width(NO_CLIP_FONT);
    a+=vgadrawtext(a,y,siz,"..");
    stop_after_this_x=tmp;
    /* now give up */
    break;
    }
  c=str[f];
  
  /*** 1st step: cover some common occurances ***/
  if(!go_through_the_motions)   /* only draw it if we really want to */
    {
    if(strchr("abdgopq68",c)!=NULL)   /* common circle position */
      fontcircle(a+s1,b+s3,siz);
    else
      {    /* common part-circle positions */
      if(strchr("cehmnrs",c)!=NULL)
        fontc_ul(a+s1,b+s3,siz);
      if(strchr("ehmnrBS35",c)!=NULL)
        fontc_ur(a+s1,b+s3,siz);
      if(strchr("cetuyCGJOQSUl035",c)!=NULL)
        fontc_ll(a+s1,b+s3,siz);
      if(strchr("suyBCDGJOQSU035",c)!=NULL)
        fontc_lr(a+s1,b+s3,siz);
      /* common line */
      if(strchr("BDEFHKLMNPR",c)!=NULL)
        vga_drawline(a,b,a,b+s4);
      }
    }

  /*** 2nd step: fill in rest - this is the *really* long, messy bit :-) ***/
  
  /*** 2a: lowercase letters ***/
  if(!go_through_the_motions)
    switch(c)
      {
      case 'a':
        vga_drawline(a+s2,b+s2,a+s2,b+s4); break;
      case 'b':
        vga_drawline(a,b,a,b+s4); break;
      case 'c':
        vga_drawline(a+s1,b+s2,a+s2,b+s2);
        vga_drawline(a+s1,b+s4,a+s2,b+s4); break;
      case 'd':
        vga_drawline(a+s2,b,a+s2,b+s4); break;
      case 'e':
        vga_drawline(a,b+s3,a+s2,b+s3);
        vga_drawline(a+s1,b+s4,a+s2,b+s4); break;
      case 'f':
        fontc_ul(a+s1,b+s1,siz); vga_drawline(a,b+s1,a,b+s4);
        vga_drawline(a,b+s2,a+s1,b+s2); break;
      case 'g':
        vga_drawline(a+s2,b+s2,a+s2,b+s5);
        fontc_l(a+s1,b+s5,siz); break;
      case 'h':
        vga_drawline(a,b,a,b+s4); vga_drawline(a+s2,b+s3,a+s2,b+s4); break;
      case 'i':
        vga_drawpixel(a,b+s1);
        vga_drawline(a,b+s2,a,b+s4);
        a+=-s1+1; break;
      case 'j':
        vga_drawline(a+s1,b+s2,a+s1,b+s5);
        fontc_lr(a,b+s5,siz);
        vga_drawpixel(a+s1,b+s1); break;
      case 'k':
        vga_drawline(a,b,a,b+s4); vga_drawline(a,b+s3,a+s1,b+s2);
        vga_drawline(a,b+s3,a+s1,b+s4); break;
      case 'l':
        vga_drawline(a,b,a,b+s3); break;
      case 'm':
        vga_drawline(a,b+s2,a,b+s4); vga_drawline(a+s2,b+s3,a+s2,b+s4);
        vga_drawline(a+s4,b+s3,a+s4,b+s4); fontc_u(a+s3,b+s3,siz);
        break;
      case 'n':
        vga_drawline(a,b+s2,a,b+s4); vga_drawline(a+s2,b+s3,a+s2,b+s4);
        break;
      case 'p':
        vga_drawline(a,b+s2,a,b+s6); break;
      case 'q':
        vga_drawline(a+s2,b+s2,a+s2,b+s6); break;
      case 'r':
        vga_drawline(a,b+s2,a,b+s4); break;
      case 's':
        vga_drawline(a,b+s3,a+s2,b+s3); vga_drawline(a+s1,b+s2,a+s2,b+s2);
        vga_drawline(a,b+s4,a+s1,b+s4);
        break;
      case 't':
        vga_drawline(a,b+s1,a,b+s3); vga_drawline(a,b+s2,a+s1,b+s2);
        break;
      case 'u':
        vga_drawline(a,b+s2,a,b+s3); vga_drawline(a+s2,b+s2,a+s2,b+s4);
        break;
      case 'v':
        vga_drawline(a,b+s2,a+s1,b+s4); vga_drawline(a+s1,b+s4,a+s2,b+s2);
        break;
      case 'w':
        vga_drawline(a,b+s2,a+s1,b+s4); vga_drawline(a+s1,b+s4,a+s2,b+s3);
        vga_drawline(a+s2,b+s3,a+s3,b+s4); vga_drawline(a+s3,b+s4,a+s4,b+s2);
        break;
      case 'x':
        vga_drawline(a,b+s2,a+s2,b+s4); vga_drawline(a,b+s4,a+s2,b+s2);
        break;
      case 'y':
        vga_drawline(a,b+s2,a,b+s3);
        vga_drawline(a+s2,b+s2,a+s2,b+s5);
        fontc_l(a+s1,b+s5,siz); break;
      case 'z':
        vga_drawline(a,b+s2,a+s2,b+s2); vga_drawline(a+s2,b+s2,a,b+s4);
        vga_drawline(a,b+s4,a+s2,b+s4); break;
      
      /*** 2b: uppercase letters ***/
  
      case 'A':
        vga_drawline(a,b+s4,a+s1,b); vga_drawline(a+s1,b,a+s2,b+s4);
        vga_drawline(a+(s1>>1),b+s2,a+s2-(s1>>1),b+s2); break;
      case 'B':
        fontc_r(a+s1,b+s1,siz);
        vga_drawline(a,b,a+s1,b); vga_drawline(a,b+s2,a+s1,b+s2);
        vga_drawline(a,b+s4,a+s1,b+s4); break;
      case 'C':
        fontc_u(a+s1,b+s1,siz); vga_drawline(a,b+s1,a,b+s3);
        break;
      case 'D':
        vga_drawline(a,b,a+s1,b);
        vga_drawline(a,b+s4,a+s1,b+s4); fontc_ur(a+s1,b+s1,siz);
        vga_drawline(a+s2,b+s1,a+s2,b+s3); break;
      case 'E':
        vga_drawline(a,b,a+s2,b); vga_drawline(a,b+s2,a+s1,b+s2);
        vga_drawline(a,b+s4,a+s2,b+s4); break;
      case 'F':
        vga_drawline(a,b,a+s2,b); vga_drawline(a,b+s2,a+s1,b+s2);
        break;
      case 'G':
        fontc_u(a+s1,b+s1,siz); vga_drawline(a,b+s1,a,b+s3);
        vga_drawline(a+s1,b+s2,a+s2,b+s2); vga_drawline(a+s2,b+s2,a+s2,b+s3);
        break;
      case 'H':
        vga_drawline(a,b+s2,a+s2,b+s2); vga_drawline(a+s2,b,a+s2,b+s4);
        break;
      case 'I':
        vga_drawline(a,b,a+s2,b); vga_drawline(a+s1,b,a+s1,b+s4);
        vga_drawline(a,b+s4,a+s2,b+s4); break;
      case 'J':
        vga_drawline(a+s2,b,a+s2,b+s3); break;
      case 'K':
        vga_drawline(a+s2,b,a,b+s2); vga_drawline(a,b+s2,a+s2,b+s4); break;
      case 'L':
        vga_drawline(a,b+s4,a+s2,b+s4); break;
      case 'M':
        vga_drawline(a,b,a+s1+(s1>>1),b+s2);
        vga_drawline(a+s1+(s1>>1),b+s2,a+s3,b);
        vga_drawline(a+s3,b,a+s3,b+s4); a-=s1; break;
      case 'N':
        vga_drawline(a,b,a+s2,b+s4); vga_drawline(a+s2,b+s4,a+s2,b); break;
      case 'Q':
        vga_drawline(a+s1,b+s3,a+s2,b+s4);
        /* FALLS THROUGH and adds an O, finishing the Q */ 
      case 'O': case '0':   /* all other numbers done later */
        fontc_u(a+s1,b+s1,siz); vga_drawline(a,b+s1,a,b+s3);
        vga_drawline(a+s2,b+s1,a+s2,b+s3); break;
      case 'R':
        vga_drawline(a+s1,b+s2,a+s2,b+s4);
        /* FALLS THROUGH and adds a P, finishing the R */
      case 'P':
        fontc_r(a+s1,b+s1,siz); vga_drawline(a,b,a+s1,b);
        vga_drawline(a,b+s2,a+s1,b+s2); break;
      case 'S':
        fontc_left(a+s1,b+s1,siz); fontc_ur(a+s1,b+s1,siz); break;
      case 'T':
        vga_drawline(a,b,a+s2,b); vga_drawline(a+s1,b,a+s1,b+s4); break;
      case 'U':
        vga_drawline(a,b,a,b+s3); vga_drawline(a+s2,b,a+s2,b+s3); break;
      case 'V':
        vga_drawline(a,b,a+s1,b+s4); vga_drawline(a+s1,b+s4,a+s2,b); break;
      case 'W':
        vga_drawline(a,b,a+s1,b+s4); vga_drawline(a+s1,b+s4,a+s2,b+s2);
        vga_drawline(a+s2,b+s2,a+s3,b+s4); vga_drawline(a+s3,b+s4,a+s4,b);
        break;
      case 'X':
        vga_drawline(a,b,a+s2,b+s4); vga_drawline(a+s2,b,a,b+s4); break;
      case 'Y':
        vga_drawline(a,b,a+s1,b+s2); vga_drawline(a+s2,b,a+s1,b+s2);
        vga_drawline(a+s1,b+s2,a+s1,b+s4); break;
      case 'Z':
        vga_drawline(a,b,a+s2,b); vga_drawline(a+s2,b,a,b+s4);
        vga_drawline(a,b+s4,a+s2,b+s4); break;
      
      /*** 2c: numbers ***/
    
      /* 0 already done */
      case '1':
        vga_drawline(a,b+s1,a+s1,b); vga_drawline(a+s1,b,a+s1,b+s4);
        vga_drawline(a,b+s4,a+s2,b+s4); break;
      case '2':
        fontc_u(a+s1,b+s1,siz); vga_drawline(a+s2,b+s1,a,b+s4);
        vga_drawline(a,b+s4,a+s2,b+s4); break;
      case '3':
        fontc_u(a+s1,b+s1,siz); fontc_lr(a+s1,b+s1,siz); break;
      case '4':
        vga_drawline(a+s1,b+s4,a+s1,b); vga_drawline(a+s1,b,a,b+s2);
        vga_drawline(a,b+s2,a+s2,b+s2); break;
      case '5':
        vga_drawline(a+s2,b,a,b); vga_drawline(a,b,a,b+s2);
        vga_drawline(a,b+s2,a+s1,b+s2); break;
      case '6':
        fontc_u(a+s1,b+s1,siz); vga_drawline(a,b+s1,a,b+s3); break;