From 9389d9755d9121c1f99a5dc208ef90a10ca1b004 Mon Sep 17 00:00:00 2001
From: Emmanuele Bassi <ebassi@linux.intel.com>
Date: Tue, 23 Dec 2008 16:40:26 +0000
Subject: [PATCH] Add the ability to set the text direction

The direction of the text depends on the locale, and it is the
basic setting needed to enable internationalization of user
interfaces.

This commit allows setting the direction of the PangoContext instance
used by Clutter by using the CLUTTER_TEXT_DIRECTION environment
variable, or by passing the --clutter-text-direction command line
argument. Valid values are:

        ltr     - for left-to-right locales
        rtl     - for right-to-left locales

The default is LTR.

Ideally, this should be a value set by the localization teams on the
PO file, but this step requires some build system surgery to allow
the translation of the Clutter strings.
---
 clutter/clutter-main.c | 68 ++++++++++++++++++++++++++++++++++++++++++--------
 1 file changed, 58 insertions(+), 10 deletions(-)

diff --git a/clutter/clutter-main.c b/clutter/clutter-main.c
index 5065610..a7ec4b9 100644
--- a/clutter/clutter-main.c
+++ b/clutter/clutter-main.c
@@ -53,21 +53,23 @@
 #include "pango/cogl-pango.h"
 
 /* main context */
-static ClutterMainContext *ClutterCntx  = NULL;
+static ClutterMainContext *ClutterCntx       = NULL;
 
 /* main lock and locking/unlocking functions */
-static GMutex *clutter_threads_mutex    = NULL;
-static GCallback clutter_threads_lock   = NULL;
-static GCallback clutter_threads_unlock = NULL;
+static GMutex *clutter_threads_mutex         = NULL;
+static GCallback clutter_threads_lock        = NULL;
+static GCallback clutter_threads_unlock      = NULL;
 
-static gboolean clutter_is_initialized  = FALSE;
-static gboolean clutter_show_fps        = FALSE;
-static gboolean clutter_fatal_warnings  = FALSE;
+static gboolean clutter_is_initialized       = FALSE;
+static gboolean clutter_show_fps             = FALSE;
+static gboolean clutter_fatal_warnings       = FALSE;
 
-static guint clutter_default_fps        = 60;
+static guint clutter_default_fps             = 60;
 
-static guint clutter_main_loop_level    = 0;
-static GSList *main_loops               = NULL;
+static guint clutter_main_loop_level         = 0;
+static GSList *main_loops                    = NULL;
+
+static PangoDirection clutter_text_direction = PANGO_DIRECTION_LTR;
 
 guint clutter_debug_flags = 0;  /* global clutter debug flag */
 
@@ -401,21 +403,51 @@ _clutter_do_pick (ClutterStage   *stage,
   return clutter_get_actor_by_gid (id);
 }
 
+static PangoDirection
+clutter_get_text_direction (void)
+{
+  const gchar *direction;
+  PangoDirection dir = PANGO_DIRECTION_LTR;
+
+  direction = g_getenv ("CLUTTER_TEXT_DIRECTION");
+  if (direction && *direction != '\0')
+    {
+      if (strcmp (direction, "rtl") == 0)
+        dir = PANGO_DIRECTION_RTL;
+      else
+        dir = PANGO_DIRECTION_LTR;
+    }
+  else
+    dir = PANGO_DIRECTION_LTR;
+
+  return dir;
+}
+
 static void
 update_pango_context (ClutterBackend     *backend,
                       ClutterMainContext *main_context)
 {
   PangoContext *context = main_context->pango_context;
+  PangoFontDescription *font_desc;
   cairo_font_options_t *font_options;
+  const gchar *font_name;
   gdouble resolution;
 
+  font_name = clutter_backend_get_font_name (backend);
+  font_desc = pango_font_description_from_string (font_name);
+
   font_options = clutter_backend_get_font_options (backend);
+
   resolution = clutter_backend_get_resolution (backend);
   if (resolution < 0)
     resolution = 96.0; /* fall back */
 
+  pango_context_set_font_description (context, font_desc);
+  pango_context_set_base_dir (context, clutter_text_direction);
   pango_cairo_context_set_font_options (context, font_options);
   pango_cairo_context_set_resolution (context, resolution);
+
+  pango_font_description_free (font_desc);
 }
 
 PangoContext *
@@ -1025,6 +1057,17 @@ clutter_get_timestamp (void)
 #endif
 }
 
+static gboolean
+clutter_arg_direction_cb (const char *key,
+                          const char *value,
+                          gpointer    user_data)
+{
+  clutter_text_direction =
+    (strcmp (value, "rtl") == 0) ? PANGO_DIRECTION_RTL
+                                 : PANGO_DIRECTION_LTR;
+
+  return TRUE;
+}
 
 #ifdef CLUTTER_ENABLE_DEBUG
 static gboolean
@@ -1098,6 +1141,8 @@ clutter_init_real (GError **error)
   cogl_pango_font_map_set_resolution (ctx->font_map, resolution);
   cogl_pango_font_map_set_use_mipmapping (ctx->font_map, TRUE);
 
+  clutter_text_direction = clutter_get_text_direction ();
+
   /* Stage will give us a GL Context etc */
   stage = clutter_stage_get_default ();
   if (!stage)
@@ -1168,6 +1213,9 @@ static GOptionEntry clutter_args[] = {
     "Default frame rate", "FPS" },
   { "g-fatal-warnings", 0, 0, G_OPTION_ARG_NONE, &clutter_fatal_warnings,
     "Make all warnings fatal", NULL },
+  { "clutter-text-direction", 0, 0, G_OPTION_ARG_CALLBACK,
+    clutter_arg_direction_cb,
+    "Direction for the text", "DIRECTION" },
 #ifdef CLUTTER_ENABLE_DEBUG
   { "clutter-debug", 0, 0, G_OPTION_ARG_CALLBACK, clutter_arg_debug_cb,
     "Clutter debugging flags to set", "FLAGS" },
-- 
2.7.4