Actual source code: text.c
2: /*
3: This file contains simple code to manage access to fonts, insuring that
4: library routines access/load fonts only once
5: */
7: #include <../src/sys/draw/impls/x/ximpl.h>
10: PetscErrorCode XiInitFonts(PetscDraw_X *);
11: PetscErrorCode XiMatchFontSize(XiFont*,int,int);
12: PetscErrorCode XiLoadFont(PetscDraw_X*,XiFont*);
13: /*
14: XiFontFixed - Return a pointer to the selected font.
16: Warning: Loads a new font for each window. This should be
17: ok because there will never be many windows and the graphics
18: are not intended to be high performance.
19: */
22: PetscErrorCode XiFontFixed(PetscDraw_X *XBWin,int w,int h,XiFont **outfont)
23: {
24: static XiFont *curfont = 0,*font;
28: if (!curfont) { XiInitFonts(XBWin);}
29: PetscNew(XiFont,&font);
30: XiMatchFontSize(font,w,h);
31: XiLoadFont(XBWin,font);
32: curfont = font;
33: *outfont = curfont;
34: return(0);
35: }
37: /* this is set by XListFonts at startup */
38: #define NFONTS 20
39: static struct {
40: int w,h,descent;
41: } nfonts[NFONTS];
42: static int act_nfonts = 0;
44: /*
45: These routines determine the font to be used based on the requested size,
46: and load it if necessary
47: */
51: PetscErrorCode XiLoadFont(PetscDraw_X *XBWin,XiFont *font)
52: {
53: char font_name[100];
54: XFontStruct *FontInfo;
55: XGCValues values ;
58: (void) sprintf(font_name,"%dx%d",font->font_w,font->font_h);
59: font->fnt = XLoadFont(XBWin->disp,font_name);
61: /* The font->descent may not have been set correctly; get it now that
62: the font has been loaded */
63: FontInfo = XQueryFont(XBWin->disp,font->fnt);
64: font->font_descent = FontInfo->descent;
65: font->font_w = FontInfo->max_bounds.rbearing - FontInfo->min_bounds.lbearing;
66: font->font_h = FontInfo->max_bounds.ascent + FontInfo->max_bounds.descent;
68: XFreeFontInfo(0,FontInfo,1);
70: /* Set the current font in the CG */
71: values.font = font->fnt ;
72: XChangeGC(XBWin->disp,XBWin->gc.set,GCFont,&values);
73: return(0);
74: }
76: /* Code to find fonts and their characteristics */
79: PetscErrorCode XiInitFonts(PetscDraw_X *XBWin)
80: {
81: char **names;
82: int cnt,i,j;
83: XFontStruct *info;
86: /* This just gets the most basic fixed-width fonts */
87: names = XListFontsWithInfo(XBWin->disp,"?x??",NFONTS,&cnt,&info);
88: j = 0;
89: for (i=0; i<cnt; i++) {
90: names[i][1] = '\0';
91: nfonts[j].w = info[i].max_bounds.width ;
92: nfonts[j].h = info[i].ascent + info[i].descent;
93: nfonts[j].descent = info[i].descent;
94: if (nfonts[j].w <= 0 || nfonts[j].h <= 0) continue;
95: j++;
96: if (j >= NFONTS) break;
97: }
98: act_nfonts = j;
99: if (cnt > 0) {
100: XFreeFontInfo(names,info,cnt);
101: }
102: /* If the above fails,try this: */
103: if (!act_nfonts) {
104: /* This just gets the most basic fixed-width fonts */
105: names = XListFontsWithInfo(XBWin->disp,"?x",NFONTS,&cnt,&info);
106: j = 0;
107: for (i=0; i<cnt; i++) {
109: size_t len;
111: PetscStrlen(names[i],&len);
112: if (len != 2) continue;
113: names[i][1] = '\0';
114: nfonts[j].w = info[i].max_bounds.width ;
115: /* nfonts[j].w = info[i].max_bounds.lbearing +
116: info[i].max_bounds.rbearing; */
117: nfonts[j].h = info[i].ascent + info[i].descent;
118: nfonts[j].descent = info[i].descent;
119: if (nfonts[j].w <= 0 || nfonts[j].h <= 0) continue;
120: j++;
121: if (j >= NFONTS) break;
122: }
123: act_nfonts = j;
124: XFreeFontInfo(names,info,cnt);
125: }
126: return(0);
127: }
131: PetscErrorCode XiMatchFontSize(XiFont *font,int w,int h)
132: {
133: int i,max,imax,tmp;
136: for (i=0; i<act_nfonts; i++) {
137: if (nfonts[i].w == w && nfonts[i].h == h) {
138: font->font_w = w;
139: font->font_h = h;
140: font->font_descent = nfonts[i].descent;
141: return(0);
142: }
143: }
145: /* determine closest fit,per max. norm */
146: imax = 0;
147: max = PetscMax(PetscAbsInt(nfonts[0].w - w),PetscAbsInt(nfonts[0].h - h));
148: for (i=1; i<act_nfonts; i++) {
149: tmp = PetscMax(PetscAbsInt(nfonts[i].w - w),PetscAbsInt(nfonts[i].h - h));
150: if (tmp < max) {max = tmp; imax = i;}
151: }
153: /* should use font with closest match */
154: font->font_w = nfonts[imax].w;
155: font->font_h = nfonts[imax].h;
156: font->font_descent = nfonts[imax].descent;
157: return(0);
158: }