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