[gtk+/gtk-style-context: 49/251] GtkThemingEngine: Add vmethod to render frames with a gap.

[Carlos Garnacho <carlosg src gnome org>]

commit ed679876a8a6be12cb4ca5875e7c2cd1a04808ee
Author: Carlos Garnacho <carlosg gnome org>
Date:   Sat Mar 27 21:23:13 2010 +0100

    GtkThemingEngine: Add vmethod to render frames with a gap.

 gtk/gtkthemingengine.c |  145 ++++++++++++++++++++++++++++++++++++++++++++++++
 gtk/gtkthemingengine.h |    9 +++
 2 files changed, 154 insertions(+), 0 deletions(-)
---
diff --git a/gtk/gtkthemingengine.c b/gtk/gtkthemingengine.c
index f824dfe..b95d6de 100644
--- a/gtk/gtkthemingengine.c
+++ b/gtk/gtkthemingengine.c
@@ -103,6 +103,15 @@ static void gtk_theming_engine_render_slider   (GtkThemingEngine *engine,
                                                 gdouble           width,
                                                 gdouble           height,
                                                 GtkOrientation    orientation);
+static void gtk_theming_engine_render_frame_gap (GtkThemingEngine *engine,
+                                                 cairo_t          *cr,
+                                                 gdouble           x,
+                                                 gdouble           y,
+                                                 gdouble           width,
+                                                 gdouble           height,
+                                                 GtkPositionType   gap_side,
+                                                 gdouble           xy0_gap,
+                                                 gdouble           xy1_gap);
 
 G_DEFINE_TYPE (GtkThemingEngine, gtk_theming_engine, G_TYPE_OBJECT)
 
@@ -144,6 +153,7 @@ gtk_theming_engine_class_init (GtkThemingEngineClass *klass)
   klass->render_layout = gtk_theming_engine_render_layout;
   klass->render_line = gtk_theming_engine_render_line;
   klass->render_slider = gtk_theming_engine_render_slider;
+  klass->render_frame_gap = gtk_theming_engine_render_frame_gap;
 
   g_type_class_add_private (object_class, sizeof (GtkThemingEnginePrivate));
 }
@@ -710,6 +720,51 @@ add_path_rounded_rectangle (cairo_t           *cr,
 }
 
 static void
+add_path_gap_side (cairo_t           *cr,
+                   GtkPositionType    gap_side,
+                   gdouble            radius,
+                   gdouble            x,
+                   gdouble            y,
+                   gdouble            width,
+                   gdouble            height,
+                   gdouble            xy0_gap,
+                   gdouble            xy1_gap)
+{
+  if (gap_side == GTK_POS_TOP)
+    {
+      cairo_move_to (cr, x, y);
+      cairo_line_to (cr, x + xy0_gap, y);
+
+      cairo_move_to (cr, x + xy1_gap, y);
+      cairo_line_to (cr, x + width, y);
+    }
+  else if (gap_side == GTK_POS_BOTTOM)
+    {
+      cairo_move_to (cr, x, y + height);
+      cairo_line_to (cr, x + xy0_gap, y + height);
+
+      cairo_move_to (cr, x + xy1_gap, y + height);
+      cairo_line_to (cr, x + width, y + height);
+    }
+  else if (gap_side == GTK_POS_LEFT)
+    {
+      cairo_move_to (cr, x, y);
+      cairo_line_to (cr, x, y + xy0_gap);
+
+      cairo_move_to (cr, x, y + xy1_gap);
+      cairo_line_to (cr, x, y + height);
+    }
+  else
+    {
+      cairo_move_to (cr, x + width, y);
+      cairo_line_to (cr, x + width, y + xy0_gap);
+
+      cairo_move_to (cr, x + width, y + xy1_gap);
+      cairo_line_to (cr, x + width, y + height);
+    }
+}
+
+static void
 color_shade (const GdkColor *color,
              gdouble         factor,
              GdkColor       *color_return)
@@ -1111,5 +1166,95 @@ gtk_theming_engine_render_slider (GtkThemingEngine *engine,
     }
 }
 
+static void
+gtk_theming_engine_render_frame_gap (GtkThemingEngine *engine,
+                                     cairo_t          *cr,
+                                     gdouble           x,
+                                     gdouble           y,
+                                     gdouble           width,
+                                     gdouble           height,
+                                     GtkPositionType   gap_side,
+                                     gdouble           xy0_gap,
+                                     gdouble           xy1_gap)
+{
+  GtkStateFlags flags;
+  GtkStateType state;
+  GdkColor *bg_color;
+  GdkColor lighter, darker;
+  guint sides;
+
+  cairo_save (cr);
+  flags = gtk_theming_engine_get_state (engine);
+
+  if (flags & GTK_STATE_FLAG_PRELIGHT)
+    state = GTK_STATE_PRELIGHT;
+  else if (flags & GTK_STATE_FLAG_INSENSITIVE)
+    state = GTK_STATE_INSENSITIVE;
+  else
+    state = GTK_STATE_NORMAL;
+
+  cairo_set_line_width (cr, 1);
+
+  gtk_theming_engine_get (engine, state,
+                          "background-color", &bg_color,
+                          NULL);
+  color_shade (bg_color, 0.7, &darker);
+  color_shade (bg_color, 1.3, &lighter);
+
+  if (gap_side == GTK_POS_RIGHT)
+    sides = SIDE_BOTTOM;
+  else if (gap_side == GTK_POS_BOTTOM)
+    sides = SIDE_RIGHT;
+  else
+    sides = SIDE_BOTTOM | SIDE_RIGHT;
+
+  if (gap_side == GTK_POS_RIGHT ||
+      gap_side == GTK_POS_BOTTOM)
+    add_path_gap_side (cr, gap_side, 0,
+                       x, y, width, height,
+                       xy0_gap, xy1_gap);
+
+  add_path_rounded_rectangle (cr, 0, sides,
+                              x, y, width, height);
+
+  cairo_set_source_rgb (cr, 0, 0, 0);
+  cairo_stroke (cr);
+
+  if (gap_side == GTK_POS_RIGHT ||
+      gap_side == GTK_POS_BOTTOM)
+    add_path_gap_side (cr, gap_side, 0,
+                       x, y, width, height,
+                       xy0_gap, xy1_gap);
+
+  add_path_rounded_rectangle (cr, 0, sides,
+                              x, y, width - 1, height - 1);
+
+  gdk_cairo_set_source_color (cr, &darker);
+  cairo_stroke (cr);
+
+  if (gap_side == GTK_POS_LEFT)
+    sides = SIDE_TOP;
+  else if (gap_side == GTK_POS_TOP)
+    sides = SIDE_LEFT;
+  else
+    sides = SIDE_TOP | SIDE_LEFT;
+
+  if (gap_side == GTK_POS_TOP ||
+      gap_side == GTK_POS_LEFT)
+    add_path_gap_side (cr, gap_side, 0,
+                       x, y, width, height,
+                       xy0_gap, xy1_gap);
+
+  add_path_rounded_rectangle (cr, 0, sides,
+                              x, y, width, height);
+
+  gdk_cairo_set_source_color (cr, &lighter);
+  cairo_stroke (cr);
+
+  cairo_restore (cr);
+
+  gdk_color_free (bg_color);
+}
+
 #define __GTK_THEMING_ENGINE_C__
 #include "gtkaliasdef.c"
diff --git a/gtk/gtkthemingengine.h b/gtk/gtkthemingengine.h
index dd02bc5..d085637 100644
--- a/gtk/gtkthemingengine.h
+++ b/gtk/gtkthemingengine.h
@@ -67,6 +67,15 @@ struct GtkThemingEngineClass
                          gdouble           y,
                          gdouble           width,
                          gdouble           height);
+  void (* render_frame_gap) (GtkThemingEngine *engine,
+                             cairo_t          *cr,
+                             gdouble           x,
+                             gdouble           y,
+                             gdouble           width,
+                             gdouble           height,
+                             GtkPositionType   gap_side,
+                             gdouble           xy0_gap,
+                             gdouble           xy1_gap);
   void (* render_check) (GtkThemingEngine *engine,
                          cairo_t          *cr,
                          gdouble           x,