Dogcows Code - chaz/openbox/blob - render/font.c

   1 /* -*- indent-tabs-mode: nil; tab-width: 4; c-basic-offset: 4; -*-
   2
   3    font.c for the Openbox window manager
   4    Copyright (c) 2006        Mikael Magnusson
   5    Copyright (c) 2003        Ben Jansens
   6    Copyright (c) 2003        Derek Foreman
   7
   8    This program is free software; you can redistribute it and/or modify
   9    it under the terms of the GNU General Public License as published by
  10    the Free Software Foundation; either version 2 of the License, or
  11    (at your option) any later version.
  12
  13    This program is distributed in the hope that it will be useful,
  14    but WITHOUT ANY WARRANTY; without even the implied warranty of
  15    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16    GNU General Public License for more details.
  17
  18    See the COPYING file for a copy of the GNU General Public License.
  19 */
  20
  21 #include "font.h"
  22 #include "color.h"
  23 #include "mask.h"
  24 #include "theme.h"
  25 #include "geom.h"
  26 #include "gettext.h"
  27
  28 #include <X11/Xft/Xft.h>
  29 #include <glib.h>
  30 #include <string.h>
  31 #include <stdlib.h>
  32 #ifdef USE_PANGO
  33 #include <locale.h>
  34 #endif
  35
  36 #define ELIPSES "..."
  37 #define ELIPSES_LENGTH(font) \
  38     (font->elipses_length + (font->shadow ? font->offset : 0))
  39
  40 #define OB_SHADOW "shadow"
  41 #define OB_SHADOW_OFFSET "shadowoffset"
  42 #define OB_SHADOW_ALPHA "shadowtint"
  43
  44 FcObjectType objs[] = {
  45     { OB_SHADOW,        FcTypeBool    },
  46     { OB_SHADOW_OFFSET, FcTypeInteger },
  47     { OB_SHADOW_ALPHA,  FcTypeInteger  }
  48 };
  49
  50 #ifdef USE_PANGO
  51 static PangoContext *context;
  52 #endif
  53 static gboolean started = FALSE;
  54
  55 static void font_startup(void)
  56 {
  57     if (!XftInit(0)) {
  58         g_warning(_("Couldn't initialize Xft."));
  59         exit(EXIT_FAILURE);
  60     }
  61
  62 #ifdef USE_PANGO
  63     g_type_init();
  64     /* these will never be freed, but we will need
  65      * them until we shut down anyway */
  66     context = pango_xft_get_context(RrDisplay(NULL), RrScreen(NULL));
  67 #endif /* USE_PANGO */
  68     /* Here we are teaching xft about the shadow, shadowoffset & shadowtint */
  69     FcNameRegisterObjectTypes(objs, (sizeof(objs) / sizeof(objs[0])));
  70 }
  71
  72 static void measure_font(RrFont *f)
  73 {
  74     /* xOff, yOff is the normal spacing to the next glyph. */
  75     XGlyphInfo info;
  76
  77     /* measure an elipses */
  78     XftTextExtentsUtf8(RrDisplay(f->inst), f->xftfont,
  79                        (FcChar8*)ELIPSES, strlen(ELIPSES), &info);
  80     f->elipses_length = (signed) info.xOff;
  81 }
  82
  83 static RrFont *openfont(const RrInstance *inst, gchar *fontstring)
  84 {
  85     /* This function is called for each font in the theme file. */
  86     /* It returns a pointer to a RrFont struct after filling it. */
  87     RrFont *out;
  88     FcPattern *pat, *match;
  89     XftFont *font;
  90     FcResult res;
  91     gint tint;
  92 #ifdef USE_PANGO
  93     guchar *tmp_string = NULL;
  94     gint tmp_int;
  95 #endif /* USE_PANGO */
  96
  97     if (!(pat = XftNameParse(fontstring)))
  98         return NULL;
  99
 100     match = XftFontMatch(RrDisplay(inst), RrScreen(inst), pat, &res);
 101     FcPatternDestroy(pat);
 102     if (!match)
 103         return NULL;
 104
 105     out = g_new(RrFont, 1);
 106     out->inst = inst;
 107 #ifdef USE_PANGO
 108     out->pango_font_description = pango_font_description_new();
 109
 110     if (FcPatternGetString(match, "family", 0, &tmp_string) !=
 111             FcResultTypeMismatch) {
 112         pango_font_description_set_family(out->pango_font_description,
 113                                           (gchar *)tmp_string);
 114         tmp_string = NULL;
 115     }
 116     if (FcPatternGetString(match, "style", 0, &tmp_string) !=
 117             FcResultTypeMismatch) {
 118         /* Bold ? */
 119         if (!g_ascii_strcasecmp("bold", (gchar *)tmp_string)) {
 120             pango_font_description_set_weight(out->pango_font_description,
 121                                               PANGO_WEIGHT_BOLD);
 122         }
 123         /* Italic ? */
 124         else if (!g_ascii_strcasecmp("italic", (gchar *)tmp_string)) {
 125             pango_font_description_set_style(out->pango_font_description,
 126                                              PANGO_STYLE_ITALIC);
 127         }
 128         tmp_string = NULL;
 129     }
 130
 131     if (FcPatternGetInteger(match, "pixelsize", 0, &tmp_int) !=
 132             FcResultTypeMismatch) {
 133         pango_font_description_set_absolute_size(out->pango_font_description,
 134                                         tmp_int*PANGO_SCALE);
 135     }
 136
 137     /* based on gtkmain.c gtk_get_default_language() */
 138     {
 139         gchar *locale, *p;
 140         PangoFontMetrics *metrics;
 141
 142         locale = g_strdup(setlocale(LC_CTYPE, NULL));
 143         if ((p = strchr(locale, '.')))
 144             *p = '\0';
 145         if ((p = strchr(locale, '@')))
 146             *p = '\0';
 147         metrics =
 148             pango_context_get_metrics(context, out->pango_font_description,
 149                                       pango_language_from_string(locale));
 150         out->pango_ascent = pango_font_metrics_get_ascent(metrics);
 151         out->pango_descent = pango_font_metrics_get_descent(metrics);
 152         g_free(locale);
 153         pango_font_metrics_unref(metrics);
 154     }
 155 #endif /* USE_PANGO */
 156
 157     if (FcPatternGetBool(match, OB_SHADOW, 0, &out->shadow) != FcResultMatch)
 158         out->shadow = FALSE;
 159
 160     if (FcPatternGetInteger(match, OB_SHADOW_OFFSET, 0, &out->offset) !=
 161         FcResultMatch)
 162         out->offset = 1;
 163
 164     if (FcPatternGetInteger(match, OB_SHADOW_ALPHA, 0, &tint) != FcResultMatch)
 165         tint = 25;
 166     if (tint > 100) tint = 100;
 167     else if (tint < -100) tint = -100;
 168     out->tint = tint;
 169
 170     font = XftFontOpenPattern(RrDisplay(inst), match);
 171     if (!font) {
 172         FcPatternDestroy(match);
 173         g_free(out);
 174         return NULL;
 175     } else
 176         out->xftfont = font;
 177
 178 #ifdef USE_PANGO
 179     /*        FcPatternDestroy(match); */
 180 #endif /* USE_PANGO */
 181     measure_font(out);
 182
 183     return out;
 184 }
 185
 186 RrFont *RrFontOpen(const RrInstance *inst, gchar *fontstring)
 187 {
 188     RrFont *out;
 189
 190     if (!started) {
 191         font_startup();
 192         started = TRUE;
 193     }
 194
 195     if ((out = openfont(inst, fontstring)))
 196         return out;
 197     g_warning(_("Unable to load font: %s\n"), fontstring);
 198     g_warning(_("Trying fallback font: %s\n"), "sans");
 199
 200     if ((out = openfont(inst, "sans")))
 201         return out;
 202     g_warning(_("Unable to load font: %s\n"), "sans");
 203
 204     return NULL;
 205 }
 206
 207 void RrFontClose(RrFont *f)
 208 {
 209     if (f) {
 210 #ifdef USE_PANGO
 211         pango_font_description_free(f->pango_font_description);
 212 #endif
 213         XftFontClose(RrDisplay(f->inst), f->xftfont);
 214         g_free(f);
 215     }
 216 }
 217
 218 static void font_measure_full(const RrFont *f, const gchar *str,
 219                               gint *x, gint *y)
 220 {
 221 #ifdef USE_PANGO
 222     PangoLayout *pl;
 223     PangoRectangle rect;
 224     pl = pango_layout_new (context);
 225     pango_layout_set_text(pl, str, -1);
 226     pango_layout_set_font_description(pl, f->pango_font_description);
 227     pango_layout_set_single_paragraph_mode(pl, TRUE);
 228     pango_layout_get_pixel_extents(pl, NULL, &rect);
 229     *x = rect.width + (f->shadow ? ABS(f->offset) : 0);
 230     *y = rect.height + (f->shadow ? ABS(f->offset) : 0);
 231     g_object_unref(pl);
 232
 233 #else
 234     XGlyphInfo info;
 235
 236     XftTextExtentsUtf8(RrDisplay(f->inst), f->xftfont,
 237                        (const FcChar8*)str, strlen(str), &info);
 238
 239     *x = (signed) info.xOff + (f->shadow ? ABS(f->offset) : 0);
 240     *y = info.height + (f->shadow ? ABS(f->offset) : 0);
 241 #endif /* USE_PANGO */
 242 }
 243
 244 RrSize *RrFontMeasureString(const RrFont *f, const gchar *str)
 245 {
 246     RrSize *size;
 247     size = g_new(RrSize, 1);
 248     font_measure_full (f, str, &size->width, &size->height);
 249     return size;
 250 }
 251
 252 gint RrFontHeight(const RrFont *f)
 253 {
 254 #ifdef USE_PANGO
 255     return (f->pango_ascent
 256             + f->pango_descent
 257            ) / PANGO_SCALE +
 258            (f->shadow ? f->offset : 0);
 259 #else
 260     return f->xftfont->ascent + f->xftfont->descent +
 261            (f->shadow ? f->offset : 0);
 262 #endif
 263 }
 264
 265 gint RrFontMaxCharWidth(const RrFont *f)
 266 {
 267     return (signed) f->xftfont->max_advance_width;
 268 }
 269
 270 #ifdef USE_PANGO
 271 static inline int font_calculate_baseline(RrFont *f, gint height)
 272 {
 273 /* For my own reference:
 274  *   _________
 275  *  ^space/2  ^height     ^baseline
 276  *  v_________|_          |
 277  *            | ^ascent   |   _           _
 278  *            | |         |  | |_ _____ _| |_ _  _
 279  *            | |         |  |  _/ -_) \ /  _| || |
 280  *            | v_________v   \__\___/_\_\\__|\_, |
 281  *            | ^descent                      |__/
 282  *  __________|_v
 283  *  ^space/2  |
 284  *  V_________v
 285  */
 286     int asc = f->pango_ascent;
 287     int ascdesc = asc + f->pango_descent;
 288     int space = height * PANGO_SCALE - ascdesc;
 289     int baseline = space / 2 + asc;
 290     return baseline / PANGO_SCALE;
 291 }
 292 #endif
 293
 294 void RrFontDraw(XftDraw *d, RrTextureText *t, RrRect *area)
 295 {
 296     gint x,y,w,h;
 297     XftColor c;
 298     GString *text;
 299     gint mw;
 300 #ifndef USE_PANGO
 301     gint mh;
 302     size_t l;
 303     gboolean shortened = FALSE;
 304 #else
 305     PangoLayout *pl;
 306     PangoRectangle rect;
 307
 308     pl = pango_layout_new (context);
 309 #endif /* USE_PANGO */
 310
 311     /* center vertically
 312      * for xft we pass the top edge of the text for positioning... */
 313 #ifndef USE_PANGO
 314     y = area->y +
 315         (area->height - RrFontHeight(t->font)) / 2;
 316 #else
 317     /* but for pango we pass the baseline, since different fonts have
 318      * different top edges. It looks stupid when the baseline of "normal"
 319      * text jumps up and down when a "strange" character is just added
 320      * to the end of the text */
 321     y = area->y +
 322         font_calculate_baseline(t->font, area->height);
 323 #endif
 324     /* the +2 and -4 leave a small blank edge on the sides */
 325     x = area->x + 2;
 326     w = area->width - 4;
 327     h = area->height;
 328
 329     text = g_string_new(t->string);
 330 #ifndef USE_PANGO
 331     l = g_utf8_strlen(text->str, -1);
 332     font_measure_full(t->font, text->str, &mw, &mh);
 333     while (l && mw > area->width) {
 334         shortened = TRUE;
 335         /* remove a character from the middle */
 336         text = g_string_erase(text, l-- / 2, 1);
 337         /* if the elipses are too large, don't show them at all */
 338         if (ELIPSES_LENGTH(t->font) > area->width)
 339             shortened = FALSE;
 340         font_measure_full(t->font, text->str, &mw, &mh);
 341         mw += ELIPSES_LENGTH(t->font);
 342     }
 343     if (shortened) {
 344         text = g_string_insert(text, (l + 1) / 2, ELIPSES);
 345         l += 3;
 346     }
 347     if (!l) return;
 348
 349     l = strlen(text->str); /* number of bytes */
 350
 351 #else
 352     pango_layout_set_text(pl, text->str, -1);
 353     pango_layout_set_font_description(pl, t->font->pango_font_description);
 354     pango_layout_set_single_paragraph_mode(pl, TRUE);
 355     pango_layout_set_width(pl, w * PANGO_SCALE);
 356     pango_layout_set_ellipsize(pl, PANGO_ELLIPSIZE_MIDDLE);
 357     /* This doesn't work with layout_line() of course */
 358 /*    pango_layout_set_alignment(pl, (PangoAlignment)(t->justify)); */
 359     pango_layout_get_pixel_extents(pl, NULL, &rect);
 360     mw = rect.width;
 361
 362 #endif /* USE_PANGO */
 363
 364     switch (t->justify) {
 365     case RR_JUSTIFY_LEFT:
 366         break;
 367     case RR_JUSTIFY_RIGHT:
 368         x += (w - mw);
 369         break;
 370     case RR_JUSTIFY_CENTER:
 371         x += (w - mw) / 2;
 372         break;
 373     }
 374
 375     if (t->font->shadow) {
 376         if (t->font->tint >= 0) {
 377             c.color.red = 0;
 378             c.color.green = 0;
 379             c.color.blue = 0;
 380             c.color.alpha = 0xffff * t->font->tint / 100;
 381             c.pixel = BlackPixel(RrDisplay(t->font->inst),
 382                                  RrScreen(t->font->inst));
 383         } else {
 384             c.color.red = 0xffff;
 385             c.color.green = 0xffff;
 386             c.color.blue = 0xffff;
 387             c.color.alpha = 0xffff * -t->font->tint / 100;
 388             c.pixel = WhitePixel(RrDisplay(t->font->inst),
 389                                  RrScreen(t->font->inst));
 390         }
 391 #ifndef USE_PANGO
 392         XftDrawStringUtf8(d, &c, t->font->xftfont, x + t->font->offset,
 393                           t->font->xftfont->ascent + y + t->font->offset,
 394                           (FcChar8*)text->str, l);
 395 #else /* USE_PANGO */
 396         /* see below... */
 397         pango_xft_render_layout_line(d, &c, pango_layout_get_line(pl, 0),
 398                                      (x + t->font->offset) * PANGO_SCALE,
 399                                      (y + t->font->offset) * PANGO_SCALE);
 400 #endif /* USE_PANGO */
 401     }
 402     c.color.red = t->color->r | t->color->r << 8;
 403     c.color.green = t->color->g | t->color->g << 8;
 404     c.color.blue = t->color->b | t->color->b << 8;
 405     c.color.alpha = 0xff | 0xff << 8; /* fully opaque text */
 406     c.pixel = t->color->pixel;
 407
 408 #ifndef USE_PANGO
 409     XftDrawStringUtf8(d, &c, t->font->xftfont, x,
 410                       t->font->xftfont->ascent + y,
 411                       (FcChar8*)text->str, l);
 412 #else /* USE_PANGO */
 413     /* layout_line() bases y on the baseline, while layout() bases y on the
 414      * top of the ink layout. We want the baseline to always be in the same
 415      * place, thusly, we use layout_line()
 416      * The actual line doesn't need to be freed (per the pango docs) */
 417     pango_xft_render_layout_line(d, &c, pango_layout_get_line(pl, 0),
 418                                  x * PANGO_SCALE, y * PANGO_SCALE);
 419     g_object_unref(pl);
 420 #endif
 421
 422     g_string_free(text, TRUE);
 423     return;
 424 }