[gtk+] win32: Add fallback code to draw theme parts

[Benjamin Otte <otte src gnome org>]

commit c98007f9fd3db6d27c6916f28d2b1867c93bd072
Author: Benjamin Otte <otte redhat com>
Date:   Wed Feb 17 04:18:29 2016 +0100

    win32: Add fallback code to draw theme parts

 gtk/gtkwin32draw.c        |  139 +++++++++++++++++++++++++++++++++++++++++++++
 gtk/gtkwin32drawprivate.h |   17 +++++-
 gtk/gtkwin32theme.c       |   11 +---
 3 files changed, 156 insertions(+), 11 deletions(-)
---
diff --git a/gtk/gtkwin32draw.c b/gtk/gtkwin32draw.c
index d80d274..1c761f2 100644
--- a/gtk/gtkwin32draw.c
+++ b/gtk/gtkwin32draw.c
@@ -19,6 +19,145 @@
 
 #include "gtkwin32drawprivate.h"
 
+static void
+gtk_cairo_set_source_sys_color (cairo_t *cr,
+                                gint     id)
+{
+  GdkRGBA rgba;
+
+  gtk_win32_get_sys_color (id, &rgba);
+  gdk_cairo_set_source_rgba (cr, &rgba);
+}
+
+static void
+draw_button (cairo_t *cr,
+             int      part,
+             int      state,
+             int      width,
+             int      height)
+{
+  gboolean is_down = (state == 3);
+  int top_color = is_down ? GTK_WIN32_SYS_COLOR_BTNSHADOW : GTK_WIN32_SYS_COLOR_BTNHIGHLIGHT;
+  int bot_color = is_down ? GTK_WIN32_SYS_COLOR_BTNHIGHLIGHT : GTK_WIN32_SYS_COLOR_BTNSHADOW;
+
+  gtk_cairo_set_source_sys_color (cr, top_color);
+  cairo_rectangle (cr, 0, 0, width - 1, 1);
+  cairo_rectangle (cr, 0, 1, 1, height - 1);
+  cairo_fill (cr);
+
+  gtk_cairo_set_source_sys_color (cr, bot_color);
+  cairo_rectangle (cr, width - 1, 0, 1, height -1);
+  cairo_rectangle (cr, 0, height - 1, width, 1);
+  cairo_fill (cr);
+
+  gtk_cairo_set_source_sys_color (cr, GTK_WIN32_SYS_COLOR_BTNFACE);
+  cairo_rectangle (cr, 1, 1, width - 2, height - 2);
+  cairo_fill (cr);
+}
+            
+static void
+draw_check (cairo_t *cr,
+            int      part,
+            int      state,
+            int      width,
+            int      height)
+{
+  gtk_cairo_set_source_sys_color (cr, GTK_WIN32_SYS_COLOR_BTNHIGHLIGHT);
+  cairo_set_line_width (cr, 1.0);
+  cairo_rectangle (cr, 0.5, 0.5, width - 1.0, height - 1.0);
+  cairo_stroke (cr);
+}
+
+static void
+draw_radio (cairo_t *cr,
+            int      part,
+            int      state,
+            int      width,
+            int      height)
+{
+  gtk_cairo_set_source_sys_color (cr, GTK_WIN32_SYS_COLOR_BTNHIGHLIGHT);
+  cairo_set_line_width (cr, 1.0);
+  cairo_arc (cr, width / 2.0, height / 2.0, MIN (width, height) / 2.0 - 0.5, 0, G_PI * 2);
+  cairo_stroke (cr);
+}
+
+typedef struct _GtkWin32ThemePart GtkWin32ThemePart;
+struct _GtkWin32ThemePart {
+  const char *class_name;
+  gint        part;
+  gint        size;
+  void        (* draw_func)             (cairo_t        *cr,
+                                         int             part,
+                                         int             state,
+                                         int             width,
+                                         int             height);
+};
+
+static GtkWin32ThemePart theme_parts[] = {
+  { "button", 1,  0, draw_button },
+  { "button", 2, 13, draw_radio },
+  { "button", 3, 13, draw_check }
+};
+
+static const GtkWin32ThemePart *
+get_theme_part (const char *class_name,
+                gint        part)
+{
+  gsize i;
+
+  for (i = 0; i < G_N_ELEMENTS (theme_parts); i++)
+    {
+      if (g_str_equal (theme_parts[i].class_name, class_name) &&
+          theme_parts[i].part == part)
+        return &theme_parts[i];
+    }
+
+  return NULL;
+}
+
+void
+gtk_win32_draw_theme_background (cairo_t    *cr,
+                                 const char *class_name,
+                                 int         part,
+                                 int         state,
+                                 int         width,
+                                 int         height)
+{
+  const GtkWin32ThemePart *theme_part;
+
+  theme_part = get_theme_part (class_name, part);
+
+  if (theme_part)
+    theme_part->draw_func (cr, part, state, width, height);
+}
+
+void
+gtk_win32_get_theme_part_size (const char *class_name,
+                               int          part,
+                               int          state,
+                               int         *width,
+                               int         *height)
+{
+  const GtkWin32ThemePart *theme_part;
+
+  theme_part = get_theme_part (class_name, part);
+
+  if (theme_part)
+    {
+      if (width)
+        *width = theme_part->size;
+      if (height)
+        *height = theme_part->size;
+    }
+  else
+    {
+      if (width)
+        *width = 1;
+      if (height)
+        *height = 1;
+    }
+}
+
 struct {
   const char *name;
   GdkRGBA rgba;
diff --git a/gtk/gtkwin32drawprivate.h b/gtk/gtkwin32drawprivate.h
index fc57cb7..f8a11ca 100644
--- a/gtk/gtkwin32drawprivate.h
+++ b/gtk/gtkwin32drawprivate.h
@@ -19,6 +19,7 @@
 #define __GTK_WIN32_DRAW_H__
 
 #include <gdk/gdk.h>
+#include <cairo.h>
 
 G_BEGIN_DECLS
 
@@ -56,8 +57,20 @@ enum {
   GTK_WIN32_SYS_COLOR_MENUBAR
 };
 
-void                    gtk_win32_get_sys_color         (gint            id,
-                                                         GdkRGBA        *color);
+void                    gtk_win32_draw_theme_background         (cairo_t        *cr,
+                                                                 const char     *class_name,
+                                                                 int             part,
+                                                                 int             state,
+                                                                 int             width,
+                                                                 int             height);
+void                    gtk_win32_get_theme_part_size           (const char     *class_name,
+                                                                 int             part,
+                                                                 int             state,
+                                                                 int            *width,
+                                                                 int            *height);
+
+void                    gtk_win32_get_sys_color                 (gint            id,
+                                                                 GdkRGBA        *color);
 
 G_END_DECLS
 
diff --git a/gtk/gtkwin32theme.c b/gtk/gtkwin32theme.c
index 8288f5d..dced7c7 100644
--- a/gtk/gtkwin32theme.c
+++ b/gtk/gtkwin32theme.c
@@ -310,7 +310,6 @@ gtk_win32_theme_create_surface (GtkWin32Theme *theme,
                                int           *y_offs_out)
 {
   cairo_surface_t *surface;
-  GdkRGBA color;
   cairo_t *cr;
   int x_offs;
   int y_offs;
@@ -378,10 +377,7 @@ gtk_win32_theme_create_surface (GtkWin32Theme *theme,
 
   cr = cairo_create (surface);
   
-  /* XXX: Do something better here (like printing the theme parts) */
-  gdk_rgba_parse (&color, "pink");
-  gdk_cairo_set_source_rgba (cr, &color);
-  cairo_paint (cr);
+  gtk_win32_draw_theme_background (cr, theme->class_name, xp_part, state, width, height);
 
   cairo_destroy (cr);
   
@@ -432,10 +428,7 @@ gtk_win32_theme_get_part_size (GtkWin32Theme  *theme,
     }
 #endif
 
-  if (width)
-    *width = 1;
-  if (height)
-    *height = 1;
+  gtk_win32_get_theme_part_size (theme->class_name, part, state, width, height);
 }
 
 int