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 (!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 (!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     gchar *locale, *p;
 139     locale = g_strdup(setlocale(LC_CTYPE, NULL));
 140     if ((p = strchr(locale, '.')))
 141         *p = '\0';
 142     if ((p = strchr(locale, '@')))
 143         *p = '\0';
 144     PangoFontMetrics *metrics =
 145         pango_context_get_metrics(context, out->pango_font_description,
 146                                   pango_language_from_string(locale));
 147     out->pango_ascent = pango_font_metrics_get_ascent(metrics);
 148     out->pango_descent = pango_font_metrics_get_descent(metrics);
 149     g_free(locale);
 150     pango_font_metrics_unref(metrics);
 151 #endif /* USE_PANGO */
 152
 153     if (FcPatternGetBool(match, OB_SHADOW, 0, &out->shadow) != FcResultMatch)
 154         out->shadow = FALSE;
 155
 156     if (FcPatternGetInteger(match, OB_SHADOW_OFFSET, 0, &out->offset) !=
 157         FcResultMatch)
 158         out->offset = 1;
 159
 160     if (FcPatternGetInteger(match, OB_SHADOW_ALPHA, 0, &tint) != FcResultMatch)
 161         tint = 25;
 162     if (tint > 100) tint = 100;
 163     else if (tint < -100) tint = -100;
 164     out->tint = tint;
 165
 166     font = XftFontOpenPattern(RrDisplay(inst), match);
 167     if (!font) {
 168         FcPatternDestroy(match);
 169         g_free(out);
 170         return NULL;
 171     } else
 172         out->xftfont = font;
 173
 174 #ifdef USE_PANGO
 175     /*        FcPatternDestroy(match); */
 176 #endif /* USE_PANGO */
 177     measure_font(out);
 178
 179     return out;
 180 }
 181
 182 RrFont *RrFontOpen(const RrInstance *inst, gchar *fontstring)
 183 {
 184     RrFont *out;
 185
 186     if (!started) {
 187         font_startup();
 188         started = TRUE;
 189     }
 190
 191     if ((out = openfont(inst, fontstring)))
 192         return out;
 193     g_warning(_("Unable to load font: %s\n"), fontstring);
 194     g_warning(_("Trying fallback font: %s\n"), "sans");
 195
 196     if ((out = openfont(inst, "sans")))
 197         return out;
 198     g_warning(_("Unable to load font: %s\n"), "sans");
 199
 200     return NULL;
 201 }
 202
 203 void RrFontClose(RrFont *f)
 204 {
 205     if (f) {
 206 #ifdef USE_PANGO
 207         pango_font_description_free(f->pango_font_description);
 208 #endif
 209         XftFontClose(RrDisplay(f->inst), f->xftfont);
 210         g_free(f);
 211     }
 212 }
 213
 214 static void font_measure_full(const RrFont *f, const gchar *str,
 215                               gint *x, gint *y)
 216 {
 217 #ifdef USE_PANGO
 218     PangoLayout *pl;
 219     PangoRectangle rect;
 220     pl = pango_layout_new (context);
 221     pango_layout_set_text(pl, str, -1);
 222     pango_layout_set_font_description(pl, f->pango_font_description);
 223     pango_layout_set_single_paragraph_mode(pl, TRUE);
 224     pango_layout_get_pixel_extents(pl, NULL, &rect);
 225     *x = rect.width + (f->shadow ? ABS(f->offset) : 0);
 226     *y = rect.height + (f->shadow ? ABS(f->offset) : 0);
 227     g_object_unref(pl);
 228
 229 #else
 230     XGlyphInfo info;
 231
 232     XftTextExtentsUtf8(RrDisplay(f->inst), f->xftfont,
 233                        (const FcChar8*)str, strlen(str), &info);
 234
 235     *x = (signed) info.xOff + (f->shadow ? ABS(f->offset) : 0);
 236     *y = info.height + (f->shadow ? ABS(f->offset) : 0);
 237 #endif /* USE_PANGO */
 238 }
 239
 240 RrSize *RrFontMeasureString(const RrFont *f, const gchar *str)
 241 {
 242     RrSize *size;
 243     size = g_new(RrSize, 1);
 244     font_measure_full (f, str, &size->width, &size->height);
 245     return size;
 246 }
 247
 248 gint RrFontHeight(const RrFont *f)
 249 {
 250 #ifdef USE_PANGO
 251     return (f->pango_ascent
 252             + f->pango_descent
 253            ) / PANGO_SCALE +
 254            (f->shadow ? f->offset : 0);
 255 #else
 256     return f->xftfont->ascent + f->xftfont->descent +
 257            (f->shadow ? f->offset : 0);
 258 #endif
 259 }
 260
 261 gint RrFontMaxCharWidth(const RrFont *f)
 262 {
 263     return (signed) f->xftfont->max_advance_width;
 264 }
 265
 266 #ifdef USE_PANGO
 267 static inline int font_calculate_baseline(RrFont *f, gint height)
 268 {
 269 /* For my own reference:
 270  *   _________
 271  *  ^space/2  ^height     ^baseline
 272  *  v_________|_          |
 273  *            | ^ascent   |   _           _
 274  *            | |         |  | |_ _____ _| |_ _  _
 275  *            | |         |  |  _/ -_) \ /  _| || |
 276  *            | v_________v   \__\___/_\_\\__|\_, |
 277  *            | ^descent                      |__/
 278  *  __________|_v
 279  *  ^space/2  |
 280  *  V_________v
 281  */
 282     int asc = f->pango_ascent;
 283     int ascdesc = asc + f->pango_descent;
 284     int space = height * PANGO_SCALE - ascdesc;
 285     int baseline = space / 2 + asc;
 286     return baseline / PANGO_SCALE;
 287 }
 288 #endif
 289
 290 void RrFontDraw(XftDraw *d, RrTextureText *t, RrRect *area)
 291 {
 292     gint x,y,w,h;
 293     XftColor c;
 294     GString *text;
 295     gint mw;
 296 #ifndef USE_PANGO
 297     gint mh;
 298     size_t l;
 299     gboolean shortened = FALSE;
 300 #else
 301     PangoLayout *pl;
 302     PangoRectangle rect;
 303
 304     pl = pango_layout_new (context);
 305 #endif /* USE_PANGO */
 306
 307     /* center vertically
 308      * for xft we pass the top edge of the text for positioning... */
 309 #ifndef USE_PANGO
 310     y = area->y +
 311         (area->height - RrFontHeight(t->font)) / 2;
 312 #else
 313     /* but for pango we pass the baseline, since different fonts have
 314      * different top edges. It looks stupid when the baseline of "normal"
 315      * text jumps up and down when a "strange" character is just added
 316      * to the end of the text */
 317     y = area->y +
 318         font_calculate_baseline(t->font, area->height);
 319 #endif
 320     /* the +2 and -4 leave a small blank edge on the sides */
 321     x = area->x + 2;
 322     w = area->width - 4;
 323     h = area->height;
 324
 325     text = g_string_new(t->string);
 326 #ifndef USE_PANGO
 327     l = g_utf8_strlen(text->str, -1);
 328     font_measure_full(t->font, text->str, &mw, &mh);
 329     while (l && mw > area->width) {
 330         shortened = TRUE;
 331         /* remove a character from the middle */
 332         text = g_string_erase(text, l-- / 2, 1);
 333         /* if the elipses are too large, don't show them at all */
 334         if (ELIPSES_LENGTH(t->font) > area->width)
 335             shortened = FALSE;
 336         font_measure_full(t->font, text->str, &mw, &mh);
 337         mw += ELIPSES_LENGTH(t->font);
 338     }
 339     if (shortened) {
 340         text = g_string_insert(text, (l + 1) / 2, ELIPSES);
 341         l += 3;
 342     }
 343     if (!l) return;
 344
 345     l = strlen(text->str); /* number of bytes */
 346
 347 #else
 348     pango_layout_set_text(pl, text->str, -1);
 349     pango_layout_set_font_description(pl, t->font->pango_font_description);
 350     pango_layout_set_single_paragraph_mode(pl, TRUE);
 351     pango_layout_set_width(pl, w * PANGO_SCALE);
 352     pango_layout_set_ellipsize(pl, PANGO_ELLIPSIZE_MIDDLE);
 353     /* This doesn't work with layout_line() of course */
 354 /*    pango_layout_set_alignment(pl, (PangoAlignment)(t->justify)); */
 355     pango_layout_get_pixel_extents(pl, NULL, &rect);
 356     mw = rect.width;
 357
 358 #endif /* USE_PANGO */
 359
 360     switch (t->justify) {
 361     case RR_JUSTIFY_LEFT:
 362         break;
 363     case RR_JUSTIFY_RIGHT:
 364         x += (w - mw);
 365         break;
 366     case RR_JUSTIFY_CENTER:
 367         x += (w - mw) / 2;
 368         break;
 369     }
 370
 371     if (t->font->shadow) {
 372         if (t->font->tint >= 0) {
 373             c.color.red = 0;
 374             c.color.green = 0;
 375             c.color.blue = 0;
 376             c.color.alpha = 0xffff * t->font->tint / 100;
 377             c.pixel = BlackPixel(RrDisplay(t->font->inst),
 378                                  RrScreen(t->font->inst));
 379         } else {
 380             c.color.red = 0xffff;
 381             c.color.green = 0xffff;
 382             c.color.blue = 0xffff;
 383             c.color.alpha = 0xffff * -t->font->tint / 100;
 384             c.pixel = WhitePixel(RrDisplay(t->font->inst),
 385                                  RrScreen(t->font->inst));
 386         }
 387 #ifndef USE_PANGO
 388         XftDrawStringUtf8(d, &c, t->font->xftfont, x + t->font->offset,
 389                           t->font->xftfont->ascent + y + t->font->offset,
 390                           (FcChar8*)text->str, l);
 391 #else /* USE_PANGO */
 392         /* see below... */
 393         pango_xft_render_layout_line(d, &c, pango_layout_get_line(pl, 0),
 394                                      (x + t->font->offset) * PANGO_SCALE,
 395                                      (y + t->font->offset) * PANGO_SCALE);
 396 #endif /* USE_PANGO */
 397     }
 398     c.color.red = t->color->r | t->color->r << 8;
 399     c.color.green = t->color->g | t->color->g << 8;
 400     c.color.blue = t->color->b | t->color->b << 8;
 401     c.color.alpha = 0xff | 0xff << 8; /* fully opaque text */
 402     c.pixel = t->color->pixel;
 403
 404 #ifndef USE_PANGO
 405     XftDrawStringUtf8(d, &c, t->font->xftfont, x,
 406                       t->font->xftfont->ascent + y,
 407                       (FcChar8*)text->str, l);
 408 #else /* USE_PANGO */
 409     /* layout_line() bases y on the baseline, while layout() bases y on the
 410      * top of the ink layout. We want the baseline to always be in the same
 411      * place, thusly, we use layout_line()
 412      * The actual line doesn't need to be freed (per the pango docs) */
 413     pango_xft_render_layout_line(d, &c, pango_layout_get_line(pl, 0),
 414                                  x * PANGO_SCALE, y * PANGO_SCALE);
 415     g_object_unref(pl);
 416 #endif
 417
 418     g_string_free(text, TRUE);
 419     return;
 420 }