[dia] [gradient] No editor, but pattern presets

[Hans Breuer <hans src gnome org>]

commit 4e505eed9e8d718081d69556deb20db4899840f9
Author: Hans Breuer <hans breuer org>
Date:   Sat Apr 12 20:31:31 2014 +0200

    [gradient] No editor, but pattern presets
    
    Implement DiaPatternSelector as a dedicated property editor which
    currently only facilitates gradient presets from background and
    foreground colors. One day it might learn to actually preview the
    patterns or even edit colors tops and other parameters.

 lib/Makefile.am          |    2 +
 lib/diapatternselector.c |  229 ++++++++++++++++++++++++++++++++++++++++++++++
 lib/diapatternselector.h |    6 +
 lib/libdia.def           |    1 -
 lib/makefile.msc         |    1 +
 lib/pattern.c            |   12 +--
 lib/pattern.h            |    2 -
 lib/prop_pattern.c       |   38 ++------
 8 files changed, 249 insertions(+), 42 deletions(-)
---
diff --git a/lib/Makefile.am b/lib/Makefile.am
index cf18864..543a6eb 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -169,6 +169,8 @@ libdia_la_SOURCES =  \
                diagdkrenderer.c \
                diapathrenderer.h \
                diapathrenderer.c \
+               diapatternselector.h \
+               diapatternselector.c \
                diatransformrenderer.h \
                diatransformrenderer.c \
                diasvgrenderer.h \
diff --git a/lib/diapatternselector.c b/lib/diapatternselector.c
new file mode 100644
index 0000000..65a04ef
--- /dev/null
+++ b/lib/diapatternselector.c
@@ -0,0 +1,229 @@
+/* Dia -- an diagram creation/manipulation program
+ * Copyright (C) 1998 Alexander Larsson
+ *
+ * diapatternselector.c - some pattern presets for property editing
+ *
+ * Copyright (C) 2014 Hans Breuer
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program 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 General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ */
+#include <config.h> 
+
+#include "diapatternselector.h"
+#include "intl.h"
+#include "attributes.h"
+
+typedef struct _DiaPatternSelector DiaPatternSelector;
+typedef struct _DiaPatternSelectorClass DiaPatternSelectorClass;
+struct _DiaPatternSelector
+{
+  GtkHBox           hbox; /*!< just containing the other two widgets */
+  GtkWidget       *state; /*!< button reflecting the state */
+  GtkWidget *menu_button; /*!< pop-up menu button to select presets */
+
+  DiaPattern    *pattern; /*!< the active pattern, maybe NULL */
+};
+struct _DiaPatternSelectorClass
+{
+  GtkHBoxClass parent_class;
+};
+
+enum {
+  DIA_PATTERNSEL_VALUE_CHANGED,
+  DIA_PATTERNSEL_LAST_SIGNAL
+};
+static guint dia_patternsel_signals[DIA_PATTERNSEL_LAST_SIGNAL] = { 0 };
+
+static DiaPattern *_create_preset_pattern (guint n);
+
+static void
+dia_pattern_selector_finalize(GObject* object)
+{
+  DiaPatternSelector *ps = (DiaPatternSelector *)object;
+  if (ps->pattern)
+    g_object_unref (ps->pattern);
+}
+
+static void
+dia_pattern_selector_class_init (DiaPatternSelector *klass)
+{
+  GObjectClass* object_class = G_OBJECT_CLASS(klass);
+
+  dia_patternsel_signals[DIA_PATTERNSEL_VALUE_CHANGED]
+      = g_signal_new("value_changed",
+                    G_TYPE_FROM_CLASS(klass),
+                    G_SIGNAL_RUN_FIRST,
+                    0, NULL, NULL,
+                    g_cclosure_marshal_VOID__VOID,
+                    G_TYPE_NONE, 0);
+  object_class->finalize = dia_pattern_selector_finalize;
+}
+
+G_DEFINE_TYPE (DiaPatternSelector, dia_pattern_selector, GTK_TYPE_HBOX);
+
+/* GUI stuff - not completely done yet 
+   - add/remove color stops
+   - toggle between radial/linear
+   - have some visual representation of the gradient
+   - provide a list of predefined like background-to-foreground,
+     horizontal/vertical/radial, ...
+ */
+static void
+_pattern_toggled(GtkWidget *wid, DiaPatternSelector *ps)
+{
+  if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON(wid))) {
+    gtk_label_set_text(GTK_LABEL(gtk_bin_get_child(GTK_BIN(wid))), _("Yes"));
+    if (!ps->pattern)
+      ps->pattern = _create_preset_pattern (0);
+  } else {
+    gtk_label_set_text(GTK_LABEL(gtk_bin_get_child(GTK_BIN(wid))), _("No"));
+    if (ps->pattern)
+      g_object_unref (ps->pattern);
+    ps->pattern = NULL;
+  }
+  g_signal_emit (G_OBJECT (ps), dia_patternsel_signals[DIA_PATTERNSEL_VALUE_CHANGED], 0);
+}
+/*! Create the pattern preset pop-up menu */
+typedef enum {
+  LEFT = 0x1,
+  DOWN = 0x2
+};
+struct _PatternPreset {
+  gchar *title;
+  guint  type;
+  guint  flags;
+} _pattern_presets[] = {
+  { N_("Horizontal"), DIA_LINEAR_GRADIENT, LEFT },
+  { N_("Diagonal"),   DIA_LINEAR_GRADIENT, LEFT|DOWN },
+  { N_("Vertical"),   DIA_LINEAR_GRADIENT, DOWN },
+  { N_("Radial"),     DIA_RADIAL_GRADIENT }
+};
+
+static DiaPattern *
+_create_preset_pattern (guint n)
+{
+  DiaPattern *pat;
+  Color       color;
+
+  g_return_val_if_fail (n < G_N_ELEMENTS (_pattern_presets), NULL);
+  switch (_pattern_presets[n].type) {
+  case DIA_LINEAR_GRADIENT:
+    pat = dia_pattern_new (_pattern_presets[n].type, 0, 0.0, 0.0);
+    if (_pattern_presets[n].flags != 0)
+      dia_pattern_set_point (pat,
+                            _pattern_presets[n].flags & LEFT ? 1.0 : 0.0,
+                            _pattern_presets[n].flags & DOWN ? 1.0 : 0.0);
+    break;
+  case DIA_RADIAL_GRADIENT:
+    pat = dia_pattern_new (_pattern_presets[n].type, 0, 0.5, 0.5);
+    dia_pattern_set_radius (pat, 0.5);
+    /* set the focal point to the center */
+    dia_pattern_set_point (pat, 0.5, 0.5);
+    break;
+  default :
+    g_assert_not_reached ();
+  }
+
+  color = attributes_get_background ();
+  dia_pattern_add_color (pat, 0.0, &color);
+  color = attributes_get_foreground ();
+  dia_pattern_add_color (pat, 1.0, &color);
+
+  return pat; 
+}
+
+#define PRESET_KEY "preset-pattern-key"
+
+static void
+_pattern_activate_preset(GtkWidget *widget, gpointer data)
+{
+  DiaPatternSelector *ps = (DiaPatternSelector *)data;
+  guint n = GPOINTER_TO_UINT(g_object_get_data (G_OBJECT(widget), PRESET_KEY));
+  if (ps->pattern)
+    g_object_unref (ps->pattern);
+  ps->pattern = _create_preset_pattern (n);
+  gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(ps->state), ps->pattern != NULL);
+  g_signal_emit (G_OBJECT (ps), dia_patternsel_signals[DIA_PATTERNSEL_VALUE_CHANGED], 0);
+}
+
+static gint
+_popup_button_press(GtkWidget *widget, GdkEventButton *event, gpointer data)
+{
+  GtkWidget *menu = gtk_menu_new();
+  guint i;
+
+  for (i = 0; i < G_N_ELEMENTS (_pattern_presets); ++i) {
+    GtkWidget *menu_item = gtk_menu_item_new_with_label(gettext(_pattern_presets[i].title));
+    g_signal_connect (G_OBJECT (menu_item), "activate",
+                     G_CALLBACK (_pattern_activate_preset), data);
+    g_object_set_data (G_OBJECT (menu_item), PRESET_KEY, GINT_TO_POINTER(i));
+    gtk_menu_shell_append (GTK_MENU_SHELL (menu), menu_item);
+    gtk_widget_show(menu_item);
+  }
+  gtk_menu_popup(GTK_MENU(menu), NULL, NULL, NULL, NULL,
+                event->button, event->time);
+  return FALSE;
+}
+static void
+dia_pattern_selector_init (DiaPatternSelector *ps)
+{
+  ps->state = gtk_toggle_button_new_with_label(_("No"));
+  g_signal_connect(G_OBJECT(ps->state), "toggled",
+                   G_CALLBACK (_pattern_toggled), ps);
+  gtk_widget_show (ps->state);
+
+  ps->menu_button = gtk_button_new();
+  gtk_container_add(GTK_CONTAINER(ps->menu_button),
+                   gtk_arrow_new(GTK_ARROW_RIGHT, GTK_SHADOW_OUT));
+  g_signal_connect(G_OBJECT(ps->menu_button), "button_press_event",
+                  G_CALLBACK(_popup_button_press), ps);
+  gtk_widget_show_all (ps->menu_button);
+
+  gtk_box_pack_start(GTK_BOX(ps), GTK_WIDGET(ps->state), TRUE, TRUE, 0);
+  gtk_box_pack_start(GTK_BOX(ps), GTK_WIDGET(ps->menu_button), FALSE, TRUE, 0);
+}
+
+/*!
+ * \brief Create the widget to work with pattern property
+ */
+GtkWidget *
+dia_pattern_selector_new (void)
+{
+  return g_object_new(dia_pattern_selector_get_type (), NULL);
+}
+
+/*!
+ * \brief Initialize the widget with pattern
+ */
+void
+dia_pattern_selector_set_pattern (GtkWidget *sel, DiaPattern *pat)
+{
+  DiaPatternSelector *ps = (DiaPatternSelector *)sel;
+  gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(ps->state), pat != NULL);
+}
+
+/*!
+ * \brief Get the pattern from the widget
+ */
+DiaPattern *
+dia_pattern_selector_get_pattern (GtkWidget *sel)
+{
+  DiaPatternSelector *ps = (DiaPatternSelector *)sel;
+
+  g_return_val_if_fail (ps != NULL, NULL);
+  if (ps->pattern)
+    return g_object_ref (ps->pattern);
+  return NULL;
+}
diff --git a/lib/diapatternselector.h b/lib/diapatternselector.h
new file mode 100644
index 0000000..b6617dd
--- /dev/null
+++ b/lib/diapatternselector.h
@@ -0,0 +1,6 @@
+#include "pattern.h"
+#include <gtk/gtk.h>
+
+GtkWidget *dia_pattern_selector_new (void);
+void dia_pattern_selector_set_pattern (GtkWidget *sel, DiaPattern *pat);
+DiaPattern *dia_pattern_selector_get_pattern (GtkWidget *sel);
diff --git a/lib/libdia.def b/lib/libdia.def
index 60e8dc4..58b621c 100644
--- a/lib/libdia.def
+++ b/lib/libdia.def
@@ -306,7 +306,6 @@ EXPORTS
  dia_pattern_set_pattern
  dia_pattern_set_point
  dia_pattern_set_radius
- dia_pattern_release
  data_add_pattern
  data_pattern
  dia_object_set_pattern
diff --git a/lib/makefile.msc b/lib/makefile.msc
index 158a888..01bbb9e 100644
--- a/lib/makefile.msc
+++ b/lib/makefile.msc
@@ -74,6 +74,7 @@ OBJECTS = \
        diainteractiverenderer.obj \
        diarenderer.obj \
        diapathrenderer.obj \
+       diapatternselector.obj \
        diatransformrenderer.obj \
        diasvgrenderer.obj \
        dynamic_obj.obj \
diff --git a/lib/pattern.c b/lib/pattern.c
index 5260254..06f1b29 100644
--- a/lib/pattern.c
+++ b/lib/pattern.c
@@ -106,7 +106,7 @@ dia_pattern_new (DiaPatternType pt, guint flags, real x, real y)
  * \brief Set the other point of the pattern
  *
  * The meaning of the point depends on the type of the pattern.
- * For line gradient it is the second point giving the direction.
+ * For linear gradient it is the second point giving the direction.
  * With a radial gradient it is the focal point.
  *
  * \ingroup DiaPattern
@@ -236,16 +236,6 @@ dia_pattern_get_fallback_color (DiaPattern *self, Color *color)
 }
 
 /*!
- * \brief Drop the reference count
- * \ingroup DiaPattern
- */
-void
-dia_pattern_release (DiaPattern *pattern)
-{
-  g_object_unref (pattern);
-}
-
-/*!
  * \brief Call the given callback for each color stop
  * \ingroup DiaPattern
  */
diff --git a/lib/pattern.h b/lib/pattern.h
index 0815f1b..5989d0b 100644
--- a/lib/pattern.h
+++ b/lib/pattern.h
@@ -56,8 +56,6 @@ void dia_pattern_get_settings (DiaPattern *pattern, DiaPatternType *type, guint
 typedef gboolean (*DiaColorStopFunc) (real ofs, const Color *col, gpointer user_data);
 void dia_pattern_foreach (DiaPattern *pattern, DiaColorStopFunc fn, gpointer user_data);
 
-void dia_pattern_release (DiaPattern *pattern);
-
 G_END_DECLS
 
 #endif /* PATTERN_H */
diff --git a/lib/prop_pattern.c b/lib/prop_pattern.c
index 3005185..93273f9 100644
--- a/lib/prop_pattern.c
+++ b/lib/prop_pattern.c
@@ -31,7 +31,7 @@
 #include "propinternals.h"
 #include "pattern.h"
 #include "prop_pattern.h"
-#include "message.h"
+#include "diapatternselector.h"
 
 static PatternProperty *
 patternprop_new(const PropDescription *pdesc, PropDescToPropPredicate reason)
@@ -49,7 +49,7 @@ static void
 patternprop_free(PatternProperty *prop) 
 {
   if (prop->pattern)
-    dia_pattern_release(prop->pattern);
+    g_object_unref (prop->pattern);
   g_free(prop);
 } 
 
@@ -206,46 +206,28 @@ patternprop_set_from_offset(PatternProperty *prop,
     struct_member(base,offset, DiaPattern *) = NULL;
 }
 
-/* GUI stuff - not yet 
-   - allow to crop
-   - maybe scale
- */
-static void
-_pattern_toggled(GtkWidget *wid)
-{
-  if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON(wid)))
-    gtk_label_set_text(GTK_LABEL(gtk_bin_get_child(GTK_BIN(wid))), _("Yes"));
-  else
-    gtk_label_set_text(GTK_LABEL(gtk_bin_get_child(GTK_BIN(wid))), _("No"));
-}
-
 static GtkWidget *
 patternprop_get_widget (PatternProperty *prop, PropDialog *dialog) 
 { 
-  GtkWidget *ret = gtk_toggle_button_new_with_label(_("No"));
-  g_signal_connect(G_OBJECT(ret), "toggled",
-                   G_CALLBACK (_pattern_toggled), NULL);
-  prophandler_connect(&prop->common, G_OBJECT(ret), "toggled");
+  GtkWidget *ret = dia_pattern_selector_new ();
+  prophandler_connect(&prop->common, G_OBJECT(ret), "value_changed");
   return ret;
 }
 
 static void
 patternprop_reset_widget(PatternProperty *prop, GtkWidget *widget)
 {
-  gtk_toggle_button_set_active(GTK_TOGGLE_BUTTON(widget),prop->pattern != NULL);
+  dia_pattern_selector_set_pattern (widget, prop->pattern);
 }
 
 static void
 patternprop_set_from_widget(PatternProperty *prop, GtkWidget *widget) 
 {
-  if (gtk_toggle_button_get_active (GTK_TOGGLE_BUTTON(widget))) {
-    if (!prop->pattern)
-      message_warning (_("Cant create pattern from scratch!"));
-  } else {
-    if (prop->pattern)
-      g_object_unref (prop->pattern);
-    prop->pattern = NULL;
-  }
+  DiaPattern *pat = dia_pattern_selector_get_pattern (widget);
+
+  if (prop->pattern)
+    g_object_unref (prop->pattern);
+  prop->pattern = pat;
 }
 
 static const PropertyOps patternprop_ops = {