cssvalue: Split number values into their own class

1 files changed, 194 insertions, 0 deletions

diff --git a/gtk/gtkcssnumbervalue.c b/gtk/gtkcssnumbervalue.c
new file mode 100644
index 0000000000..e845a686c6
--- /dev/null
+++ b/gtk/gtkcssnumbervalue.c
@@ -0,0 +1,194 @@
+/* GTK - The GIMP Toolkit
+ * Copyright (C) 2011 Red Hat, Inc.
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "config.h"
+
+#include "gtkcssnumbervalueprivate.h"
+
+#include "gtkstylepropertyprivate.h"
+
+struct _GtkCssValue {
+  GTK_CSS_VALUE_BASE
+  GtkCssUnit unit;
+  double value;
+};
+
+static void
+gtk_css_value_number_free (GtkCssValue *value)
+{
+  g_slice_free (GtkCssValue, value);
+}
+
+static gboolean
+gtk_css_value_number_equal (const GtkCssValue *number1,
+                            const GtkCssValue *number2)
+{
+  return number1->unit == number2->unit &&
+         number1->value == number2->value;
+}
+
+static void
+gtk_css_value_number_print (const GtkCssValue *number,
+                            GString           *string)
+{
+  char buf[G_ASCII_DTOSTR_BUF_SIZE];
+
+  const char *names[] = {
+    /* [GTK_CSS_NUMBER] = */ "",
+    /* [GTK_CSS_PERCENT] = */ "%",
+    /* [GTK_CSS_PX] = */ "px",
+    /* [GTK_CSS_PT] = */ "pt",
+    /* [GTK_CSS_EM] = */ "em",
+    /* [GTK_CSS_EX] = */ "ex",
+    /* [GTK_CSS_PC] = */ "pc",
+    /* [GTK_CSS_IN] = */ "in",
+    /* [GTK_CSS_CM] = */ "cm",
+    /* [GTK_CSS_MM] = */ "mm",
+    /* [GTK_CSS_RAD] = */ "rad",
+    /* [GTK_CSS_DEG] = */ "deg",
+    /* [GTK_CSS_GRAD] = */ "grad",
+    /* [GTK_CSS_TURN] = */ "turn",
+  };
+
+  g_ascii_dtostr (buf, sizeof (buf), number->value);
+  g_string_append (string, buf);
+  if (number->value != 0.0)
+    g_string_append (string, names[number->unit]);
+}
+
+static const GtkCssValueClass GTK_CSS_VALUE_NUMBER = {
+  gtk_css_value_number_free,
+  gtk_css_value_number_equal,
+  gtk_css_value_number_print
+};
+
+GtkCssValue *
+_gtk_css_number_value_new (double     value,
+                           GtkCssUnit unit)
+{
+  static GtkCssValue zero_singleton = { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_NUMBER, 0 };
+  static GtkCssValue px_singletons[] = {
+    { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 0 },
+    { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 1 },
+    { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 2 },
+    { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 3 },
+    { &GTK_CSS_VALUE_NUMBER, 1, GTK_CSS_PX, 4 },
+  };
+  GtkCssValue *result;
+
+  if (unit == GTK_CSS_NUMBER && value == 0)
+    return _gtk_css_value_ref (&zero_singleton);
+
+  if (unit == GTK_CSS_PX &&
+      (value == 0 ||
+       value == 1 ||
+       value == 2 ||
+       value == 3 ||
+       value == 4))
+    {
+      return _gtk_css_value_ref (&px_singletons[(int) value]);
+    }
+
+  result = _gtk_css_value_new (GtkCssValue, &GTK_CSS_VALUE_NUMBER);
+  result->unit = unit;
+  result->value = value;
+
+  return result;
+}
+
+GtkCssValue *
+_gtk_css_number_value_parse (GtkCssParser           *parser,
+                             GtkCssNumberParseFlags  flags)
+{
+  GtkCssNumber number;
+
+  g_return_val_if_fail (parser != NULL, NULL);
+
+  if (!_gtk_css_parser_read_number (parser, &number, flags))
+    return NULL;
+  
+  return _gtk_css_number_value_new (number.value, number.unit);
+}
+
+double
+_gtk_css_number_value_get (const GtkCssValue *number,
+                           double             one_hundred_percent)
+{
+  g_return_val_if_fail (number != NULL, 0.0);
+  g_return_val_if_fail (number->class == &GTK_CSS_VALUE_NUMBER, 0.0);
+
+  if (number->unit == GTK_CSS_PERCENT)
+    return number->value * one_hundred_percent / 100;
+  else
+    return number->value;
+}
+
+GtkCssValue *
+_gtk_css_number_value_compute (GtkCssValue     *number,
+                               GtkStyleContext *context)
+{
+  g_return_val_if_fail (number->class == &GTK_CSS_VALUE_NUMBER, NULL);
+
+  switch (number->unit)
+    {
+    default:
+      g_assert_not_reached();
+      /* fall through */
+    case GTK_CSS_PERCENT:
+    case GTK_CSS_NUMBER:
+    case GTK_CSS_PX:
+    case GTK_CSS_DEG:
+      return _gtk_css_value_ref (number);
+    case GTK_CSS_PT:
+      return _gtk_css_number_value_new (number->value * 96.0 / 72.0,
+                                        GTK_CSS_PX);
+    case GTK_CSS_PC:
+      return _gtk_css_number_value_new (number->value * 96.0 / 72.0 * 12.0,
+                                        GTK_CSS_PX);
+      break;
+    case GTK_CSS_IN:
+      return _gtk_css_number_value_new (number->value * 96.0,
+                                        GTK_CSS_PX);
+      break;
+    case GTK_CSS_CM:
+      return _gtk_css_number_value_new (number->value * 96.0 * 0.39370078740157477,
+                                        GTK_CSS_PX);
+      break;
+    case GTK_CSS_MM:
+      return _gtk_css_number_value_new (number->value * 96.0 * 0.039370078740157477,
+                                        GTK_CSS_PX);
+      break;
+    case GTK_CSS_EM:
+      return _gtk_css_number_value_new (number->value * _gtk_css_value_get_double (_gtk_style_context_peek_property (context, "font-size")),
+                                        GTK_CSS_PX);
+      break;
+    case GTK_CSS_EX:
+      /* for now we pretend ex is half of em */
+      return _gtk_css_number_value_new (number->value * 0.5 * _gtk_css_value_get_double (_gtk_style_context_peek_property (context, "font-size")),
+                                        GTK_CSS_PX);
+    case GTK_CSS_RAD:
+      return _gtk_css_number_value_new (number->value * 360.0 / (2 * G_PI),
+                                        GTK_CSS_DEG);
+    case GTK_CSS_GRAD:
+      return _gtk_css_number_value_new (number->value * 360.0 / 400.0,
+                                        GTK_CSS_DEG);
+    case GTK_CSS_TURN:
+      return _gtk_css_number_value_new (number->value * 360.0,
+                                        GTK_CSS_DEG);
+    }
+}
+