Actual source code: text.c
1: #define PETSC_DLL
3: /*
4: This file contains simple code to manage access to fonts, insuring that
5: library routines access/load fonts only once
6: */
8: #include ../src/sys/draw/impls/x/ximpl.h
11: PetscErrorCode XiInitFonts(PetscDraw_X *);
12: PetscErrorCode XiMatchFontSize(XiFont*,int,int);
13: PetscErrorCode XiLoadFont(PetscDraw_X*,XiFont*);
14: /*
15: XiFontFixed - Return a pointer to the selected font.
17: Warning: Loads a new font for each window. This should be
18: ok because there will never be many windows and the graphics
19: are not intended to be high performance.
20: */
23: PetscErrorCode XiFontFixed(PetscDraw_X *XBWin,int w,int h,XiFont **outfont)
24: {
25: static XiFont *curfont = 0,*font;
29: if (!curfont) { XiInitFonts(XBWin);}
30: PetscNew(XiFont,&font);
31: XiMatchFontSize(font,w,h);
32: XiLoadFont(XBWin,font);
33: curfont = font;
34: *outfont = curfont;
35: return(0);
36: }
38: /* this is set by XListFonts at startup */
39: #define NFONTS 20
40: static struct {
41: int w,h,descent;
42: } nfonts[NFONTS];
43: static int act_nfonts = 0;
45: /*
46: These routines determine the font to be used based on the requested size,
47: and load it if necessary
48: */
52: PetscErrorCode XiLoadFont(PetscDraw_X *XBWin,XiFont *font)
53: {
54: char font_name[100];
55: XFontStruct *FontInfo;
56: XGCValues values ;
59: (void) sprintf(font_name,"%dx%d",font->font_w,font->font_h);
60: font->fnt = XLoadFont(XBWin->disp,font_name);
62: /* The font->descent may not have been set correctly; get it now that
63: the font has been loaded */
64: FontInfo = XQueryFont(XBWin->disp,font->fnt);
65: font->font_descent = FontInfo->descent;
67: XFreeFontInfo(0,FontInfo,1);
69: /* Set the current font in the CG */
70: values.font = font->fnt ;
71: XChangeGC(XBWin->disp,XBWin->gc.set,GCFont,&values);
72: return(0);
73: }
75: /* Code to find fonts and their characteristics */
78: PetscErrorCode XiInitFonts(PetscDraw_X *XBWin)
79: {
80: char **names;
81: int cnt,i,j;
82: XFontStruct *info;
85: /* This just gets the most basic fixed-width fonts */
86: names = XListFontsWithInfo(XBWin->disp,"?x??",NFONTS,&cnt,&info);
87: j = 0;
88: for (i=0; i<cnt; i++) {
89: names[i][1] = '\0';
90: nfonts[j].w = info[i].max_bounds.width ;
91: nfonts[j].h = info[i].ascent + info[i].descent;
92: nfonts[j].descent = info[i].descent;
93: if (nfonts[j].w <= 0 || nfonts[j].h <= 0) continue;
94: j++;
95: if (j >= NFONTS) break;
96: }
97: act_nfonts = j;
98: if (cnt > 0) {
99: XFreeFontInfo(names,info,cnt);
100: }
101: /* If the above fails,try this: */
102: if (!act_nfonts) {
103: /* This just gets the most basic fixed-width fonts */
104: names = XListFontsWithInfo(XBWin->disp,"?x",NFONTS,&cnt,&info);
105: j = 0;
106: for (i=0; i<cnt; i++) {
108: size_t len;
110: PetscStrlen(names[i],&len);
111: if (len != 2) continue;
112: names[i][1] = '\0';
113: nfonts[j].w = info[i].max_bounds.width ;
114: /* nfonts[j].w = info[i].max_bounds.lbearing +
115: info[i].max_bounds.rbearing; */
116: nfonts[j].h = info[i].ascent + info[i].descent;
117: nfonts[j].descent = info[i].descent;
118: if (nfonts[j].w <= 0 || nfonts[j].h <= 0) continue;
119: j++;
120: if (j >= NFONTS) break;
121: }
122: act_nfonts = j;
123: XFreeFontInfo(names,info,cnt);
124: }
125: return(0);
126: }
130: PetscErrorCode XiMatchFontSize(XiFont *font,int w,int h)
131: {
132: int i,max,imax,tmp;
135: for (i=0; i<act_nfonts; i++) {
136: if (nfonts[i].w == w && nfonts[i].h == h) {
137: font->font_w = w;
138: font->font_h = h;
139: font->font_descent = nfonts[i].descent;
140: return(0);
141: }
142: }
144: /* determine closest fit,per max. norm */
145: imax = 0;
146: max = PetscMax(PetscAbsInt(nfonts[0].w - w),PetscAbsInt(nfonts[0].h - h));
147: for (i=1; i<act_nfonts; i++) {
148: tmp = PetscMax(PetscAbsInt(nfonts[i].w - w),PetscAbsInt(nfonts[i].h - h));
149: if (tmp < max) {max = tmp; imax = i;}
150: }
152: /* should use font with closest match */
153: font->font_w = nfonts[imax].w;
154: font->font_h = nfonts[imax].h;
155: font->font_descent = nfonts[imax].descent;
156: return(0);
157: }