Pileus Git - ~andy/gtk/blob - gtk/gtkcssnumbervalue.c

   1 /* GTK - The GIMP Toolkit
   2  * Copyright (C) 2011 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, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 #include "config.h"
  19
  20 #include "gtkcssnumbervalueprivate.h"
  21
  22 #include "gtkcssenumvalueprivate.h"
  23 #include "gtkstylepropertyprivate.h"
  24
  25 struct _GtkCssValue {
  26   GTK_CSS_VALUE_BASE
  27   GtkCssUnit unit;
  28   double value;
  29 };
  30
  31 static void
  32 gtk_css_value_number_free (GtkCssValue *value)
  33 {
  34   g_slice_free (GtkCssValue, value);
  35 }
  36
  37 static GtkCssValue *
  38 gtk_css_value_number_compute (GtkCssValue        *number,
  39                               guint               property_id,
  40                               GtkStyleContext    *context,
  41                               GtkCssDependencies *dependencies)
  42 {
  43   GtkBorderStyle border_style;
  44
  45   /* I don't like this special case being here in this generic code path, but no idea where else to put it. */
  46   switch (property_id)
  47     {
  48       case GTK_CSS_PROPERTY_BORDER_TOP_WIDTH:
  49         border_style = _gtk_css_border_style_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_BORDER_TOP_STYLE));
  50         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  51           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  52         break;
  53       case GTK_CSS_PROPERTY_BORDER_RIGHT_WIDTH:
  54         border_style = _gtk_css_border_style_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_BORDER_RIGHT_STYLE));
  55         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  56           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  57         break;
  58       case GTK_CSS_PROPERTY_BORDER_BOTTOM_WIDTH:
  59         border_style = _gtk_css_border_style_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_BORDER_BOTTOM_STYLE));
  60         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  61           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  62         break;
  63       case GTK_CSS_PROPERTY_BORDER_LEFT_WIDTH:
  64         border_style = _gtk_css_border_style_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_BORDER_LEFT_STYLE));
  65         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  66           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  67         break;
  68       case GTK_CSS_PROPERTY_OUTLINE_WIDTH:
  69         border_style = _gtk_css_border_style_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_OUTLINE_STYLE));
  70         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  71           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  72         break;
  73       default:
  74         break;
  75     }
  76
  77   switch (number->unit)
  78     {
  79     default:
  80       g_assert_not_reached();
  81       /* fall through */
  82     case GTK_CSS_PERCENT:
  83     case GTK_CSS_NUMBER:
  84     case GTK_CSS_PX:
  85     case GTK_CSS_DEG:
  86     case GTK_CSS_S:
  87       return _gtk_css_value_ref (number);
  88     case GTK_CSS_PT:
  89       return _gtk_css_number_value_new (number->value * 96.0 / 72.0,
  90                                         GTK_CSS_PX);
  91     case GTK_CSS_PC:
  92       return _gtk_css_number_value_new (number->value * 96.0 / 72.0 * 12.0,
  93                                         GTK_CSS_PX);
  94       break;
  95     case GTK_CSS_IN:
  96       return _gtk_css_number_value_new (number->value * 96.0,
  97                                         GTK_CSS_PX);
  98       break;
  99     case GTK_CSS_CM:
 100       return _gtk_css_number_value_new (number->value * 96.0 * 0.39370078740157477,
 101                                         GTK_CSS_PX);
 102       break;
 103     case GTK_CSS_MM:
 104       return _gtk_css_number_value_new (number->value * 96.0 * 0.039370078740157477,
 105                                         GTK_CSS_PX);
 106       break;
 107     case GTK_CSS_EM:
 108       *dependencies = GTK_CSS_DEPENDS_ON_FONT_SIZE;
 109       return _gtk_css_number_value_new (number->value *
 110                                         _gtk_css_number_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_FONT_SIZE), 100),
 111                                         GTK_CSS_PX);
 112       break;
 113     case GTK_CSS_EX:
 114       /* for now we pretend ex is half of em */
 115       *dependencies = GTK_CSS_DEPENDS_ON_FONT_SIZE;
 116       return _gtk_css_number_value_new (number->value * 0.5 *
 117                                         _gtk_css_number_value_get (_gtk_style_context_peek_property (context, GTK_CSS_PROPERTY_FONT_SIZE), 100),
 118                                         GTK_CSS_PX);
 119     case GTK_CSS_RAD:
 120       return _gtk_css_number_value_new (number->value * 360.0 / (2 * G_PI),
 121                                         GTK_CSS_DEG);
 122     case GTK_CSS_GRAD:
 123       return _gtk_css_number_value_new (number->value * 360.0 / 400.0,
 124                                         GTK_CSS_DEG);
 125     case GTK_CSS_TURN:
 126       return _gtk_css_number_value_new (number->value * 360.0,
 127                                         GTK_CSS_DEG);
 128     case GTK_CSS_MS:
 129       return _gtk_css_number_value_new (number->value / 1000.0,
 130                                         GTK_CSS_S);
 131     }
 132 }
 133
 134 static gboolean
 135 gtk_css_value_number_equal (const GtkCssValue *number1,
 136                             const GtkCssValue *number2)
 137 {
 138   return number1->unit == number2->unit &&
 139          number1->value == number2->value;
 140 }
 141
 142 static GtkCssValue *
 143 gtk_css_value_number_transition (GtkCssValue *start,
 144                                  GtkCssValue *end,
 145                                  double       progress)
 146 {
 147   /* FIXME: This needs to be supported at least for percentages,
 148    * but for that we kinda need to support calc(5px + 50%) */
 149   if (start->unit != end->unit)
 150     return NULL;
 151
 152   return _gtk_css_number_value_new (start->value + (end->value - start->value) * progress,
 153                                     start->unit);
 154 }
 155
 156 static void
 157 gtk_css_value_number_print (const GtkCssValue *number,
 158                             GString           *string)
 159 {
 160   char buf[G_ASCII_DTOSTR_BUF_SIZE];
 161
 162   const char *names[] = {
 163     /* [GTK_CSS_NUMBER] = */ "",
 164     /* [GTK_CSS_PERCENT] = */ "%",
 165     /* [GTK_CSS_PX] = */ "px",
 166     /* [GTK_CSS_PT] = */ "pt",
 167     /* [GTK_CSS_EM] = */ "em",
 168     /* [GTK_CSS_EX] = */ "ex",
 169     /* [GTK_CSS_PC] = */ "pc",
 170     /* [GTK_CSS_IN] = */ "in",
 171     /* [GTK_CSS_CM] = */ "cm",
 172     /* [GTK_CSS_MM] = */ "mm",
 173     /* [GTK_CSS_RAD] = */ "rad",
 174     /* [GTK_CSS_DEG] = */ "deg",
 175     /* [GTK_CSS_GRAD] = */ "grad",
 176     /* [GTK_CSS_TURN] = */ "turn",
 177     /* [GTK_CSS_S] = */ "s",
 178     /* [GTK_CSS_MS] = */ "ms",
 179   };
 180
 181   g_ascii_dtostr (buf, sizeof (buf), number->value);
 182   g_string_append (string, buf);
 183   if (number->value != 0.0)
 184     g_string_append (string, names[number->unit]);
 185 }
 186
 187 static const GtkCssValueClass GTK_CSS_VALUE_NUMBER = {
 188   gtk_css_value_number_free,
 189   gtk_css_value_number_compute,
 190   gtk_css_value_number_equal,
 191   gtk_css_value_number_transition,
 192   gtk_css_value_number_print
 193 };
 194
 195 GtkCssValue *
 196 _gtk_css_number_value_new (double     value,
 197                            GtkCssUnit unit)
 198 {
 199   static GtkCssValue zero_singleton = { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_NUMBER, 0 };
 200   static GtkCssValue px_singletons[] = {
 201     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 0 },
 202     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 1 },
 203     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 2 },
 204     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 3 },
 205     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 4 },
 206   };
 207   GtkCssValue *result;
 208
 209   if (unit == GTK_CSS_NUMBER && value == 0)
 210     return _gtk_css_value_ref (&zero_singleton);
 211
 212   if (unit == GTK_CSS_PX &&
 213       (value == 0 ||
 214        value == 1 ||
 215        value == 2 ||
 216        value == 3 ||
 217        value == 4))
 218     {
 219       return _gtk_css_value_ref (&px_singletons[(int) value]);
 220     }
 221
 222   result = _gtk_css_value_new (GtkCssValue, &GTK_CSS_VALUE_NUMBER);
 223   result->unit = unit;
 224   result->value = value;
 225
 226   return result;
 227 }
 228
 229 GtkCssUnit
 230 _gtk_css_number_value_get_unit (const GtkCssValue *value)
 231 {
 232   g_return_val_if_fail (value->class == &GTK_CSS_VALUE_NUMBER, GTK_CSS_NUMBER);
 233
 234   return value->unit;
 235 }
 236
 237 double
 238 _gtk_css_number_value_get (const GtkCssValue *number,
 239                            double             one_hundred_percent)
 240 {
 241   g_return_val_if_fail (number != NULL, 0.0);
 242   g_return_val_if_fail (number->class == &GTK_CSS_VALUE_NUMBER, 0.0);
 243
 244   if (number->unit == GTK_CSS_PERCENT)
 245     return number->value * one_hundred_percent / 100;
 246   else
 247     return number->value;
 248 }
 249