Pileus Git - ~andy/gtk/blob - gdk/gdkpango.c

   1 /* GDK - The GIMP Drawing Kit
   2  * Copyright (C) 2000 Red Hat, Inc.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19
  20 #include "gdkcolor.h"
  21 #include "gdkgc.h"
  22 #include "gdkpango.h"
  23 #include "gdkprivate.h"
  24
  25 #define GDK_INFO_KEY "gdk-info"
  26
  27 typedef struct _GdkPangoContextInfo GdkPangoContextInfo;
  28
  29 struct _GdkPangoContextInfo
  30 {
  31   GdkColormap *colormap;
  32 };
  33
  34 static void gdk_pango_get_item_properties (PangoItem      *item,
  35                                            PangoUnderline *uline,
  36                                            gint           *rise,
  37                                            PangoAttrColor *fg_color,
  38                                            gboolean       *fg_set,
  39                                            PangoAttrColor *bg_color,
  40                                            gboolean       *bg_set,
  41                                            gboolean       *shape_set,
  42                                            PangoRectangle *ink_rect,
  43                                            PangoRectangle *logical_rect);
  44
  45 static void
  46 gdk_pango_context_destroy (GdkPangoContextInfo *info)
  47 {
  48   gdk_colormap_unref (info->colormap);
  49   g_free (info);
  50 }
  51
  52 static GdkPangoContextInfo *
  53 gdk_pango_context_get_info (PangoContext *context, gboolean create)
  54 {
  55   GdkPangoContextInfo *info =
  56     g_object_get_qdata (G_OBJECT (context),
  57                         g_quark_try_string (GDK_INFO_KEY));
  58   if (!info && create)
  59     {
  60       info = g_new (GdkPangoContextInfo, 1);
  61       info->colormap = NULL;
  62
  63       g_object_set_qdata_full (G_OBJECT (context),
  64                                g_quark_from_static_string (GDK_INFO_KEY),
  65                                info, (GDestroyNotify)gdk_pango_context_destroy);
  66     }
  67
  68   return info;
  69 }
  70
  71 static GdkGC *
  72 gdk_pango_get_gc (PangoContext   *context,
  73                   PangoAttrColor *fg_color,
  74                   GdkGC          *base_gc)
  75 {
  76   GdkPangoContextInfo *info;
  77   GdkColormap *colormap;
  78   GdkColor color;
  79
  80   g_return_val_if_fail (context != NULL, NULL);
  81
  82   info = gdk_pango_context_get_info (context, FALSE);
  83
  84   if (info && info->colormap)
  85     colormap = info->colormap;
  86   else
  87     colormap = gdk_colormap_get_system();
  88
  89   /* FIXME. FIXME. FIXME. Only works for true color */
  90
  91   color.red = fg_color->red;
  92   color.green = fg_color->green;
  93   color.blue = fg_color->blue;
  94
  95   if (gdk_colormap_alloc_color (colormap, &color, FALSE, TRUE))
  96     {
  97       GdkGC *result = gdk_gc_new (gdk_parent_root);
  98       gdk_gc_copy (result, base_gc);
  99       gdk_gc_set_foreground (result, &color);
 100
 101       return result;
 102     }
 103   else
 104     return gdk_gc_ref (base_gc);
 105 }
 106
 107 static void
 108 gdk_pango_free_gc (PangoContext *context,
 109                    GdkGC        *gc)
 110 {
 111   gdk_gc_unref (gc);
 112 }
 113
 114 void
 115 gdk_pango_context_set_colormap (PangoContext *context,
 116                                 GdkColormap  *colormap)
 117 {
 118   GdkPangoContextInfo *info;
 119
 120   g_return_if_fail (context != NULL);
 121
 122   info = gdk_pango_context_get_info (context, TRUE);
 123   g_return_if_fail (info != NULL);
 124
 125   if (info->colormap != colormap)
 126     {
 127       if (info->colormap)
 128         gdk_colormap_unref (info->colormap);
 129
 130       info->colormap = colormap;
 131
 132       if (info->colormap)
 133         gdk_colormap_ref (info->colormap);
 134     }
 135 }
 136
 137 /**
 138  * gdk_draw_layout_line:
 139  * @drawable:  the drawable on which to draw the line
 140  * @gc:        base graphics to use
 141  * @x:         the x position of start of string (in pixels)
 142  * @y:         the y position of baseline (in pixels)
 143  * @line:      a #PangoLayoutLine
 144  *
 145  * Render a #PangoLayoutLine onto an GDK drawable
 146  */
 147 void
 148 gdk_draw_layout_line (GdkDrawable      *drawable,
 149                       GdkGC            *gc,
 150                       gint              x,
 151                       gint              y,
 152                       PangoLayoutLine  *line)
 153 {
 154   GSList *tmp_list = line->runs;
 155   PangoRectangle overall_rect;
 156   PangoRectangle logical_rect;
 157   PangoRectangle ink_rect;
 158   PangoContext *context;
 159   gint x_off = 0;
 160   gint rise = 0;
 161
 162   g_return_if_fail (drawable != NULL);
 163   g_return_if_fail (gc != NULL);
 164   g_return_if_fail (line != NULL);
 165
 166   context = pango_layout_get_context (line->layout);
 167
 168   pango_layout_line_get_extents (line,NULL, &overall_rect);
 169
 170   while (tmp_list)
 171     {
 172       PangoUnderline uline = PANGO_UNDERLINE_NONE;
 173       PangoLayoutRun *run = tmp_list->data;
 174       PangoAttrColor fg_color, bg_color;
 175       gboolean fg_set, bg_set, shape_set;
 176       GdkGC *fg_gc;
 177       gint risen_y;
 178
 179       tmp_list = tmp_list->next;
 180
 181       gdk_pango_get_item_properties (run->item, &uline,
 182                                      &rise,
 183                                      &fg_color, &fg_set,
 184                                      &bg_color, &bg_set,
 185                                      &shape_set,
 186                                      &ink_rect,
 187                                      &logical_rect);
 188
 189       /* we subtract the rise because X coordinates are upside down */
 190       risen_y = y - rise / PANGO_SCALE;
 191
 192       if (!shape_set)
 193         {
 194           if (uline == PANGO_UNDERLINE_NONE)
 195             pango_glyph_string_extents (run->glyphs, run->item->analysis.font,
 196                                         NULL, &logical_rect);
 197           else
 198             pango_glyph_string_extents (run->glyphs, run->item->analysis.font,
 199                                         &ink_rect, &logical_rect);
 200         }
 201
 202       if (bg_set)
 203         {
 204           GdkGC *bg_gc = gdk_pango_get_gc (context, &bg_color, gc);
 205
 206           gdk_draw_rectangle (drawable, bg_gc, TRUE,
 207                               x + (x_off + logical_rect.x) / PANGO_SCALE,
 208                               risen_y + overall_rect.y / PANGO_SCALE,
 209                               logical_rect.width / PANGO_SCALE,
 210                               overall_rect.height / PANGO_SCALE);
 211
 212           gdk_pango_free_gc (context, bg_gc);
 213         }
 214
 215       if (fg_set)
 216         fg_gc = gdk_pango_get_gc (context, &fg_color, gc);
 217       else
 218         fg_gc = gc;
 219
 220       if (!shape_set)
 221         gdk_draw_glyphs (drawable, fg_gc, run->item->analysis.font,
 222                          x + x_off / PANGO_SCALE,
 223                          risen_y,
 224                          run->glyphs);
 225
 226       switch (uline)
 227         {
 228         case PANGO_UNDERLINE_NONE:
 229           break;
 230         case PANGO_UNDERLINE_DOUBLE:
 231           gdk_draw_line (drawable, fg_gc,
 232                          x + (x_off + ink_rect.x) / PANGO_SCALE - 1,
 233                          risen_y + 3,
 234                          x + (x_off + ink_rect.x + ink_rect.width) / PANGO_SCALE,
 235                          risen_y + 3);
 236           /* Fall through */
 237         case PANGO_UNDERLINE_SINGLE:
 238           gdk_draw_line (drawable, fg_gc,
 239                          x + (x_off + ink_rect.x) / PANGO_SCALE - 1,
 240                          risen_y + 1,
 241                          x + (x_off + ink_rect.x + ink_rect.width) / PANGO_SCALE,
 242                          risen_y + 1);
 243           break;
 244         case PANGO_UNDERLINE_LOW:
 245           gdk_draw_line (drawable, fg_gc,
 246                          x + (x_off + ink_rect.x) / PANGO_SCALE - 1,
 247                          risen_y + (ink_rect.y + ink_rect.height) / PANGO_SCALE + 1,
 248                          x + (x_off + ink_rect.x + ink_rect.width) / PANGO_SCALE,
 249                          risen_y + (ink_rect.y + ink_rect.height) / PANGO_SCALE + 1);
 250           break;
 251         }
 252
 253       if (fg_set)
 254         gdk_pango_free_gc (context, fg_gc);
 255
 256       x_off += logical_rect.width;
 257     }
 258 }
 259
 260 /**
 261  * gdk_draw_layout:
 262  * @drawable:  the drawable on which to draw string
 263  * @gc:        base graphics context to use
 264  * @x:         the X position of the left of the layout (in pixels)
 265  * @y:         the Y position of the top of the layout (in pixels)
 266  * @layout:    a #PangoLayout
 267  *
 268  * Render a #PangoLayout onto a GDK drawable
 269  */
 270 void
 271 gdk_draw_layout (GdkDrawable     *drawable,
 272                  GdkGC           *gc,
 273                  int              x,
 274                  int              y,
 275                  PangoLayout     *layout)
 276 {
 277   PangoLayoutIter *iter;
 278
 279   g_return_if_fail (drawable != NULL);
 280   g_return_if_fail (gc != NULL);
 281   g_return_if_fail (layout != NULL);
 282
 283   iter = pango_layout_get_iter (layout);
 284
 285   do
 286     {
 287       PangoRectangle logical_rect;
 288       PangoLayoutLine *line;
 289       int baseline;
 290
 291       line = pango_layout_iter_get_line (iter);
 292
 293       pango_layout_iter_get_line_extents (iter, NULL, &logical_rect);
 294       baseline = pango_layout_iter_get_baseline (iter);
 295
 296       gdk_draw_layout_line (drawable, gc,
 297                             x + logical_rect.x / PANGO_SCALE,
 298                             y + baseline / PANGO_SCALE,
 299                             line);
 300     }
 301   while (pango_layout_iter_next_line (iter));
 302
 303   pango_layout_iter_free (iter);
 304 }
 305
 306 static void
 307 gdk_pango_get_item_properties (PangoItem      *item,
 308                                PangoUnderline *uline,
 309                                gint           *rise,
 310                                PangoAttrColor *fg_color,
 311                                gboolean       *fg_set,
 312                                PangoAttrColor *bg_color,
 313                                gboolean       *bg_set,
 314                                gboolean       *shape_set,
 315                                PangoRectangle *ink_rect,
 316                                PangoRectangle *logical_rect)
 317 {
 318   GSList *tmp_list = item->extra_attrs;
 319
 320   if (fg_set)
 321     *fg_set = FALSE;
 322
 323   if (bg_set)
 324     *bg_set = FALSE;
 325
 326   if (shape_set)
 327     *shape_set = FALSE;
 328
 329   if (rise)
 330     *rise = 0;
 331
 332   while (tmp_list)
 333     {
 334       PangoAttribute *attr = tmp_list->data;
 335
 336       switch (attr->klass->type)
 337         {
 338         case PANGO_ATTR_UNDERLINE:
 339           if (uline)
 340             *uline = ((PangoAttrInt *)attr)->value;
 341           break;
 342
 343         case PANGO_ATTR_FOREGROUND:
 344           if (fg_color)
 345             *fg_color = *((PangoAttrColor *)attr);
 346           if (fg_set)
 347             *fg_set = TRUE;
 348
 349           break;
 350
 351         case PANGO_ATTR_BACKGROUND:
 352           if (bg_color)
 353             *bg_color = *((PangoAttrColor *)attr);
 354           if (bg_set)
 355             *bg_set = TRUE;
 356
 357           break;
 358
 359         case PANGO_ATTR_SHAPE:
 360           if (shape_set)
 361             *shape_set = TRUE;
 362           if (logical_rect)
 363             *logical_rect = ((PangoAttrShape *)attr)->logical_rect;
 364           if (ink_rect)
 365             *ink_rect = ((PangoAttrShape *)attr)->ink_rect;
 366           break;
 367
 368         case PANGO_ATTR_RISE:
 369           if (rise)
 370             *rise = ((PangoAttrInt *)attr)->value;
 371           break;
 372
 373         default:
 374           break;
 375         }
 376       tmp_list = tmp_list->next;
 377     }
 378 }
 379