git.sur5r.net Git - glabels/blob - src/font-sample.c

   1 /*
   2  *  font-sample.c
   3  *  Copyright (C) 2009  Jim Evins <evins@snaught.com>.
   4  *
   5  *  This file is part of gLabels.
   6  *
   7  *  gLabels 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 3 of the License, or
  10  *  (at your option) any later version.
  11  *
  12  *  gLabels 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  *  You should have received a copy of the GNU General Public License
  18  *  along with gLabels.  If not, see <http://www.gnu.org/licenses/>.
  19  */
  20
  21 #include <config.h>
  22
  23 #include "font-sample.h"
  24
  25 #include "marshal.h"
  26 #include "color.h"
  27
  28
  29 /*===========================================*/
  30 /* Private macros and constants.             */
  31 /*===========================================*/
  32
  33 #define MARGIN 2
  34
  35
  36 /*===========================================*/
  37 /* Private types                             */
  38 /*===========================================*/
  39
  40 struct _glFontSamplePrivate {
  41
  42         gchar *sample_text;
  43
  44         gchar *font_family;
  45 };
  46
  47
  48 /*===========================================*/
  49 /* Private globals                           */
  50 /*===========================================*/
  51
  52
  53 /*===========================================*/
  54 /* Local function prototypes                 */
  55 /*===========================================*/
  56
  57 static void       gl_font_sample_finalize     (GObject        *object);
  58
  59 static void       style_set_cb                (GtkWidget      *widget,
  60                                                GtkStyle       *previous_style);
  61
  62 static void       redraw                      (glFontSample   *this);
  63
  64 static gboolean   expose_event_cb             (GtkWidget      *widget,
  65                                                GdkEventExpose *event);
  66
  67 static void       draw_sample                 (glFontSample   *this,
  68                                                cairo_t        *cr);
  69
  70
  71
  72 /****************************************************************************/
  73 /* Boilerplate Object stuff.                                                */
  74 /****************************************************************************/
  75 G_DEFINE_TYPE (glFontSample, gl_font_sample, GTK_TYPE_DRAWING_AREA);
  76
  77
  78 /*****************************************************************************/
  79 /* Class Init Function.                                                      */
  80 /*****************************************************************************/
  81 static void
  82 gl_font_sample_class_init (glFontSampleClass *class)
  83 {
  84         GObjectClass   *gobject_class = G_OBJECT_CLASS (class);
  85         GtkWidgetClass *widget_class = GTK_WIDGET_CLASS (class);
  86
  87         gl_font_sample_parent_class = g_type_class_peek_parent (class);
  88
  89         gobject_class->finalize    = gl_font_sample_finalize;
  90
  91         widget_class->expose_event = expose_event_cb;
  92         widget_class->style_set    = style_set_cb;
  93 }
  94
  95
  96 /*****************************************************************************/
  97 /* Object Instance Init Function.                                            */
  98 /*****************************************************************************/
  99 static void
 100 gl_font_sample_init (glFontSample *this)
 101 {
 102         GTK_WIDGET_SET_FLAGS (GTK_WIDGET (this), GTK_NO_WINDOW);
 103
 104         this->priv = g_new0 (glFontSamplePrivate, 1);
 105 }
 106
 107
 108 /*****************************************************************************/
 109 /* Finalize Method.                                                          */
 110 /*****************************************************************************/
 111 static void
 112 gl_font_sample_finalize (GObject *object)
 113 {
 114         glFontSample *this = GL_FONT_SAMPLE (object);
 115
 116         g_return_if_fail (object != NULL);
 117         g_return_if_fail (GL_IS_FONT_SAMPLE (object));
 118
 119         g_free (this->priv->sample_text);
 120         g_free (this->priv->font_family);
 121         g_free (this->priv);
 122
 123         G_OBJECT_CLASS (gl_font_sample_parent_class)->finalize (object);
 124 }
 125
 126
 127 /*****************************************************************************/
 128 /** New Object Generator.                                                    */
 129 /*****************************************************************************/
 130 GtkWidget *
 131 gl_font_sample_new (gint         w,
 132                     gint         h,
 133                     const gchar *sample_text,
 134                     const gchar *font_family)
 135 {
 136         glFontSample *this;
 137
 138         this = g_object_new (GL_TYPE_FONT_SAMPLE, NULL);
 139
 140         this->priv->sample_text = g_strdup (sample_text);
 141         this->priv->font_family = g_strdup (font_family);
 142
 143         gtk_widget_set_size_request (GTK_WIDGET (this), w, h);
 144
 145         return GTK_WIDGET (this);
 146 }
 147
 148
 149 /*--------------------------------------------------------------------------*/
 150 /* Style set handler (updates colors when style/theme changes).             */
 151 /*--------------------------------------------------------------------------*/
 152 static void
 153 style_set_cb (GtkWidget        *widget,
 154               GtkStyle         *previous_style)
 155 {
 156         redraw (GL_FONT_SAMPLE (widget));
 157 }
 158
 159
 160 /*****************************************************************************/
 161 /* Request redraw.                                                           */
 162 /*****************************************************************************/
 163 static void
 164 redraw (glFontSample  *this)
 165 {
 166         GdkRegion *region;
 167
 168         if (GTK_WIDGET_REALIZED (GTK_WIDGET (this)))
 169         {
 170                 /* redraw the cairo canvas forcing an expose event */
 171                 region = gdk_drawable_get_clip_region (GTK_WIDGET (this)->window);
 172                 gdk_window_invalidate_region (GTK_WIDGET (this)->window, region, TRUE);
 173                 gdk_region_destroy (region);
 174         }
 175 }
 176
 177
 178 /*****************************************************************************/
 179 /* "Expose event" callback.                                                  */
 180 /*****************************************************************************/
 181 static gboolean
 182 expose_event_cb (GtkWidget      *widget,
 183                  GdkEventExpose *event)
 184 {
 185         cairo_t *cr;
 186
 187         cr = gdk_cairo_create (widget->window);
 188
 189         cairo_rectangle (cr,
 190                         event->area.x, event->area.y,
 191                         event->area.width, event->area.height);
 192         cairo_clip (cr);
 193
 194         cairo_translate (cr, widget->allocation.x, widget->allocation.y);
 195
 196         draw_sample (GL_FONT_SAMPLE (widget), cr);
 197
 198         cairo_destroy (cr);
 199
 200         return FALSE;
 201 }
 202
 203
 204 /*****************************************************************************/
 205 /* Draw sample.                                                              */
 206 /*****************************************************************************/
 207 static void
 208 draw_sample (glFontSample *this,
 209              cairo_t       *cr)
 210 {
 211         GtkStyle             *style;
 212         gdouble               w, h;
 213         guint                 fill_color, line_color;
 214         PangoLayout          *layout;
 215         PangoFontDescription *desc;
 216         PangoRectangle        ink_rect, logical_rect;
 217         gdouble               layout_x, layout_y, layout_width, layout_height;
 218
 219
 220
 221         w = GTK_WIDGET (this)->allocation.width;
 222         h = GTK_WIDGET (this)->allocation.height;
 223
 224
 225         style = gtk_widget_get_style (GTK_WIDGET (this));
 226         if ( GTK_WIDGET_IS_SENSITIVE (GTK_WIDGET (this)) )
 227         {
 228                 fill_color = gl_color_from_gdk_color (&style->light[GTK_STATE_NORMAL]);
 229                 line_color = gl_color_from_gdk_color (&style->fg[GTK_STATE_NORMAL]);
 230         }
 231         else
 232         {
 233                 fill_color = GL_COLOR_NONE;
 234                 line_color = gl_color_from_gdk_color (&style->fg[GTK_STATE_INSENSITIVE]);
 235         }
 236
 237
 238         cairo_set_antialias (cr, CAIRO_ANTIALIAS_NONE);
 239
 240         cairo_rectangle( cr, 0, 0, w-1, h-1 );
 241
 242         cairo_set_source_rgba (cr, GL_COLOR_RGBA_ARGS (fill_color));
 243         cairo_fill_preserve( cr );
 244
 245         cairo_set_source_rgb (cr, GL_COLOR_RGB_ARGS (line_color));
 246         cairo_set_line_width (cr, 1.0);
 247         cairo_stroke (cr);
 248
 249
 250         cairo_set_antialias (cr, CAIRO_ANTIALIAS_DEFAULT);
 251
 252
 253         layout = pango_cairo_create_layout (cr);
 254
 255         desc = pango_font_description_new ();
 256         pango_font_description_set_family (desc, this->priv->font_family);
 257         pango_font_description_set_weight (desc, PANGO_WEIGHT_NORMAL);
 258         pango_font_description_set_style  (desc, PANGO_STYLE_NORMAL);
 259         pango_font_description_set_size   (desc, 0.6 * h * PANGO_SCALE);
 260
 261         pango_layout_set_font_description (layout, desc);
 262         pango_font_description_free       (desc);
 263
 264         pango_layout_set_text (layout, this->priv->sample_text, -1);
 265         pango_layout_set_width (layout, -1);
 266         pango_layout_get_pixel_extents (layout, &ink_rect, &logical_rect);
 267         layout_width  = MAX (logical_rect.width, ink_rect.width);
 268         layout_height = MAX (logical_rect.height, ink_rect.height);
 269
 270         layout_x = (w - layout_width) / 2.0;
 271         layout_y = (h - layout_height) / 2.0;
 272
 273         if (ink_rect.x < logical_rect.x)
 274         {
 275                 layout_x += logical_rect.x - ink_rect.x;
 276         }
 277
 278         if (ink_rect.y < logical_rect.y)
 279         {
 280                 layout_y += logical_rect.y - ink_rect.y;
 281         }
 282
 283         cairo_set_source_rgba (cr, GL_COLOR_RGBA_ARGS (line_color));
 284         cairo_move_to (cr, layout_x, layout_y);
 285         pango_cairo_show_layout (cr, layout);
 286
 287         g_object_unref (layout);
 288 }
 289
 290
 291
 292 /*
 293  * Local Variables:       -- emacs
 294  * mode: C                -- emacs
 295  * c-basic-offset: 8      -- emacs
 296  * tab-width: 8           -- emacs
 297  * indent-tabs-mode: nil  -- emacs
 298  * End:                   -- emacs
 299  */