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                               GtkStyleProviderPrivate *provider,
  41                               GtkCssComputedValues    *values,
  42                               GtkCssComputedValues    *parent_values,
  43                               GtkCssDependencies      *dependencies)
  44 {
  45   GtkBorderStyle border_style;
  46
  47   /* I don't like this special case being here in this generic code path, but no idea where else to put it. */
  48   switch (property_id)
  49     {
  50       case GTK_CSS_PROPERTY_BORDER_TOP_WIDTH:
  51         border_style = _gtk_css_border_style_value_get (_gtk_css_computed_values_get_value (values, GTK_CSS_PROPERTY_BORDER_TOP_STYLE));
  52         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  53           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  54         break;
  55       case GTK_CSS_PROPERTY_BORDER_RIGHT_WIDTH:
  56         border_style = _gtk_css_border_style_value_get (_gtk_css_computed_values_get_value (values, GTK_CSS_PROPERTY_BORDER_RIGHT_STYLE));
  57         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  58           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  59         break;
  60       case GTK_CSS_PROPERTY_BORDER_BOTTOM_WIDTH:
  61         border_style = _gtk_css_border_style_value_get (_gtk_css_computed_values_get_value (values, GTK_CSS_PROPERTY_BORDER_BOTTOM_STYLE));
  62         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  63           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  64         break;
  65       case GTK_CSS_PROPERTY_BORDER_LEFT_WIDTH:
  66         border_style = _gtk_css_border_style_value_get (_gtk_css_computed_values_get_value (values, GTK_CSS_PROPERTY_BORDER_LEFT_STYLE));
  67         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  68           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  69         break;
  70       case GTK_CSS_PROPERTY_OUTLINE_WIDTH:
  71         border_style = _gtk_css_border_style_value_get (_gtk_css_computed_values_get_value (values, GTK_CSS_PROPERTY_OUTLINE_STYLE));
  72         if (border_style == GTK_BORDER_STYLE_NONE || border_style == GTK_BORDER_STYLE_HIDDEN)
  73           return _gtk_css_number_value_new (0, GTK_CSS_PX);
  74         break;
  75       default:
  76         break;
  77     }
  78
  79   switch (number->unit)
  80     {
  81     default:
  82       g_assert_not_reached();
  83       /* fall through */
  84     case GTK_CSS_PERCENT:
  85     case GTK_CSS_NUMBER:
  86     case GTK_CSS_PX:
  87     case GTK_CSS_DEG:
  88     case GTK_CSS_S:
  89       return _gtk_css_value_ref (number);
  90     case GTK_CSS_PT:
  91       return _gtk_css_number_value_new (number->value * 96.0 / 72.0,
  92                                         GTK_CSS_PX);
  93     case GTK_CSS_PC:
  94       return _gtk_css_number_value_new (number->value * 96.0 / 72.0 * 12.0,
  95                                         GTK_CSS_PX);
  96       break;
  97     case GTK_CSS_IN:
  98       return _gtk_css_number_value_new (number->value * 96.0,
  99                                         GTK_CSS_PX);
 100       break;
 101     case GTK_CSS_CM:
 102       return _gtk_css_number_value_new (number->value * 96.0 * 0.39370078740157477,
 103                                         GTK_CSS_PX);
 104       break;
 105     case GTK_CSS_MM:
 106       return _gtk_css_number_value_new (number->value * 96.0 * 0.039370078740157477,
 107                                         GTK_CSS_PX);
 108       break;
 109     case GTK_CSS_EM:
 110       *dependencies = GTK_CSS_DEPENDS_ON_FONT_SIZE;
 111       return _gtk_css_number_value_new (number->value *
 112                                         _gtk_css_number_value_get (_gtk_css_computed_values_get_value (values, GTK_CSS_PROPERTY_FONT_SIZE), 100),
 113                                         GTK_CSS_PX);
 114       break;
 115     case GTK_CSS_EX:
 116       /* for now we pretend ex is half of em */
 117       *dependencies = GTK_CSS_DEPENDS_ON_FONT_SIZE;
 118       return _gtk_css_number_value_new (number->value * 0.5 *
 119                                         _gtk_css_number_value_get (_gtk_css_computed_values_get_value (values, GTK_CSS_PROPERTY_FONT_SIZE), 100),
 120                                         GTK_CSS_PX);
 121     case GTK_CSS_RAD:
 122       return _gtk_css_number_value_new (number->value * 360.0 / (2 * G_PI),
 123                                         GTK_CSS_DEG);
 124     case GTK_CSS_GRAD:
 125       return _gtk_css_number_value_new (number->value * 360.0 / 400.0,
 126                                         GTK_CSS_DEG);
 127     case GTK_CSS_TURN:
 128       return _gtk_css_number_value_new (number->value * 360.0,
 129                                         GTK_CSS_DEG);
 130     case GTK_CSS_MS:
 131       return _gtk_css_number_value_new (number->value / 1000.0,
 132                                         GTK_CSS_S);
 133     }
 134 }
 135
 136 static gboolean
 137 gtk_css_value_number_equal (const GtkCssValue *number1,
 138                             const GtkCssValue *number2)
 139 {
 140   return number1->unit == number2->unit &&
 141          number1->value == number2->value;
 142 }
 143
 144 static GtkCssValue *
 145 gtk_css_value_number_transition (GtkCssValue *start,
 146                                  GtkCssValue *end,
 147                                  guint        property_id,
 148                                  double       progress)
 149 {
 150   /* FIXME: This needs to be supported at least for percentages,
 151    * but for that we kinda need to support calc(5px + 50%) */
 152   if (start->unit != end->unit)
 153     return NULL;
 154
 155   return _gtk_css_number_value_new (start->value + (end->value - start->value) * progress,
 156                                     start->unit);
 157 }
 158
 159 static void
 160 gtk_css_value_number_print (const GtkCssValue *number,
 161                             GString           *string)
 162 {
 163   char buf[G_ASCII_DTOSTR_BUF_SIZE];
 164
 165   const char *names[] = {
 166     /* [GTK_CSS_NUMBER] = */ "",
 167     /* [GTK_CSS_PERCENT] = */ "%",
 168     /* [GTK_CSS_PX] = */ "px",
 169     /* [GTK_CSS_PT] = */ "pt",
 170     /* [GTK_CSS_EM] = */ "em",
 171     /* [GTK_CSS_EX] = */ "ex",
 172     /* [GTK_CSS_PC] = */ "pc",
 173     /* [GTK_CSS_IN] = */ "in",
 174     /* [GTK_CSS_CM] = */ "cm",
 175     /* [GTK_CSS_MM] = */ "mm",
 176     /* [GTK_CSS_RAD] = */ "rad",
 177     /* [GTK_CSS_DEG] = */ "deg",
 178     /* [GTK_CSS_GRAD] = */ "grad",
 179     /* [GTK_CSS_TURN] = */ "turn",
 180     /* [GTK_CSS_S] = */ "s",
 181     /* [GTK_CSS_MS] = */ "ms",
 182   };
 183
 184   g_ascii_dtostr (buf, sizeof (buf), number->value);
 185   g_string_append (string, buf);
 186   if (number->value != 0.0)
 187     g_string_append (string, names[number->unit]);
 188 }
 189
 190 static const GtkCssValueClass GTK_CSS_VALUE_NUMBER = {
 191   gtk_css_value_number_free,
 192   gtk_css_value_number_compute,
 193   gtk_css_value_number_equal,
 194   gtk_css_value_number_transition,
 195   gtk_css_value_number_print
 196 };
 197
 198 GtkCssValue *
 199 _gtk_css_number_value_new (double     value,
 200                            GtkCssUnit unit)
 201 {
 202   static GtkCssValue zero_singleton = { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_NUMBER, 0 };
 203   static GtkCssValue px_singletons[] = {
 204     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 0 },
 205     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 1 },
 206     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 2 },
 207     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 3 },
 208     { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 4 },
 209   };
 210   GtkCssValue *result;
 211
 212   if (unit == GTK_CSS_NUMBER && value == 0)
 213     return _gtk_css_value_ref (&zero_singleton);
 214
 215   if (unit == GTK_CSS_PX &&
 216       (value == 0 ||
 217        value == 1 ||
 218        value == 2 ||
 219        value == 3 ||
 220        value == 4))
 221     {
 222       return _gtk_css_value_ref (&px_singletons[(int) value]);
 223     }
 224
 225   result = _gtk_css_value_new (GtkCssValue, &GTK_CSS_VALUE_NUMBER);
 226   result->unit = unit;
 227   result->value = value;
 228
 229   return result;
 230 }
 231
 232 GtkCssUnit
 233 _gtk_css_number_value_get_unit (const GtkCssValue *value)
 234 {
 235   g_return_val_if_fail (value->class == &GTK_CSS_VALUE_NUMBER, GTK_CSS_NUMBER);
 236
 237   return value->unit;
 238 }
 239
 240 double
 241 _gtk_css_number_value_get (const GtkCssValue *number,
 242                            double             one_hundred_percent)
 243 {
 244   g_return_val_if_fail (number != NULL, 0.0);
 245   g_return_val_if_fail (number->class == &GTK_CSS_VALUE_NUMBER, 0.0);
 246
 247   if (number->unit == GTK_CSS_PERCENT)
 248     return number->value * one_hundred_percent / 100;
 249   else
 250     return number->value;
 251 }
 252