Correct switched return value of EAST/WEST.

2006-08-20  Behdad Esfahbod  <behdad@gnome.org>

        * pango/pango-matrix.c (pango_matrix_to_gravity): Correct switched
        return value of EAST/WEST.

        * pango/pango-types.h (PangoGravity): Add PANGO_GRAVITY_AUTO.
        * pango/pango-context.h: Add pango_context_get_gravity().

        * examples/renderdemo.c (parse_gravity), (parse_options):
        * pango/pango-context.c (pango_context_init),
        (update_resolved_gravity), (pango_context_set_matrix),
        (pango_context_set_base_gravity), (pango_context_get_gravity),
        (itemize_state_init), (get_shaper_and_font):
        * pango/pango-layout.c (line_set_resolved_dir):
        * pango/pangocairo-fcfont.c (pango_cairo_fc_font_get_metrics),
        (pango_cairo_fc_font_glyph_extents_cache_init),
        (_pango_cairo_fc_font_new):
        * pango/pangofc-fontmap.c (pango_fc_make_pattern),
        (pango_fc_font_map_load_fontset):
        * pango/pango.def:
        * docs/pango-sections.txt:
        * docs/tmpl/main.sgml:
        Update to above.

8 files changed, 65 insertions, 12 deletions

diff --git a/pango/pango-context.c b/pango/pango-context.c
index ac6db552..b3dec728 100644
--- a/pango/pango-context.c
+++ b/pango/pango-context.c
@@ -37,6 +37,7 @@ struct _PangoContext
   PangoLanguage *language;
   PangoDirection base_dir;
   PangoGravity base_gravity;
+  PangoGravity resolved_gravity;
 
   PangoFontDescription *font_desc;
 
@@ -59,7 +60,7 @@ static void
 pango_context_init (PangoContext *context)
 {
   context->base_dir = PANGO_DIRECTION_WEAK_LTR;
-  context->base_gravity = PANGO_GRAVITY_SOUTH;
+  context->resolved_gravity = context->base_gravity = PANGO_GRAVITY_SOUTH;
   context->language = NULL;
   context->font_map = NULL;
 
@@ -128,6 +129,15 @@ pango_context_new (void)
   return context;
 }
 
+static void
+update_resolved_gravity (PangoContext *context)
+{
+  if (context->base_gravity == PANGO_GRAVITY_AUTO)
+    context->resolved_gravity = pango_matrix_to_gravity (context->matrix);
+  else
+    context->resolved_gravity = context->base_gravity;
+}
+
 /**
  * pango_context_set_matrix:
  * @context: a #PangoContext
@@ -155,6 +165,8 @@ pango_context_set_matrix (PangoContext       *context,
     context->matrix = pango_matrix_copy (matrix);
   else
     context->matrix = NULL;
+
+  update_resolved_gravity (context);
 }
 
 /**
@@ -423,6 +435,8 @@ pango_context_set_base_gravity (PangoContext  *context,
   g_return_if_fail (context != NULL);
 
   context->base_gravity = gravity;
+
+  update_resolved_gravity (context);
 }
 
 /**
@@ -444,6 +458,27 @@ pango_context_get_base_gravity (PangoContext *context)
   return context->base_gravity;
 }
 
+/**
+ * pango_context_get_gravity:
+ * @context: a #PangoContext
+ * 
+ * Retrieves the gravity for the context. This is similar to
+ * pango_context_get_base_gravity(), except for when the base gravity
+ * is %PANGO_GRAVITY_AUTO for which pango_matrix_to_gravity() is used
+ * to return the gravity from the current context matrix.
+ * 
+ * Return value: the resolved gravity for the context.
+ *
+ * Since: 1.16
+ **/
+PangoGravity
+pango_context_get_gravity (PangoContext *context)
+{
+  g_return_val_if_fail (context != NULL, PANGO_GRAVITY_SOUTH);
+
+  return context->resolved_gravity;
+}
+
 /**********************************************************************/
 
 static gboolean
@@ -711,10 +746,10 @@ itemize_state_init (ItemizeState      *state,
   /* FIXME: Set gravity to base gravity for now, until we do
    * proper gravity assignment.
    */
-  state->gravity = context->base_gravity;
+  state->gravity = context->resolved_gravity;
 
-  state->centered_baseline = context->base_gravity == PANGO_GRAVITY_EAST
-			  || context->base_gravity == PANGO_GRAVITY_WEST;
+  state->centered_baseline = context->resolved_gravity == PANGO_GRAVITY_EAST
+			  || context->resolved_gravity == PANGO_GRAVITY_WEST;
 
   /* Initialize the attribute iterator
    */
@@ -1014,6 +1049,7 @@ get_shaper_and_font (ItemizeState      *state,
 	{
 	  case PANGO_GRAVITY_SOUTH:
 	  case PANGO_GRAVITY_NORTH:
+	  case PANGO_GRAVITY_AUTO:
 	  default:
             script = state->script;
 	    break;
diff --git a/pango/pango-context.h b/pango/pango-context.h
index 97af918c..25bdf4ab 100644
--- a/pango/pango-context.h
+++ b/pango/pango-context.h
@@ -81,6 +81,7 @@ PangoDirection            pango_context_get_base_dir         (PangoContext
 void                      pango_context_set_base_gravity     (PangoContext               *context,
 							      PangoGravity                gravity);
 PangoGravity              pango_context_get_base_gravity     (PangoContext               *context);
+PangoGravity              pango_context_get_gravity          (PangoContext               *context);
 
 void                        pango_context_set_matrix (PangoContext      *context,
 						      const PangoMatrix *matrix);
diff --git a/pango/pango-layout.c b/pango/pango-layout.c
index 4c9ec92f..1a5917ba 100644
--- a/pango/pango-layout.c
+++ b/pango/pango-layout.c
@@ -3028,7 +3028,7 @@ line_set_resolved_dir (PangoLayoutLine *line,
    * A similar dance is performed in pango-context.c:
    * itemize_state_add_character().  Keep in synch.
    */
-  switch (pango_context_get_base_gravity (line->layout->context))
+  switch (pango_context_get_gravity (line->layout->context))
     {
     case PANGO_GRAVITY_SOUTH:
     default:
diff --git a/pango/pango-matrix.c b/pango/pango-matrix.c
index 322a4931..e63ecab1 100644
--- a/pango/pango-matrix.c
+++ b/pango/pango-matrix.c
@@ -258,7 +258,7 @@ pango_matrix_get_font_scale_factor (const PangoMatrix *matrix)
  * in a #PangoMatrix.
  *
  * Return value: the gravity of @matrix, which will never be
- * %PANGO_GRAVITY_AUTO
+ * %PANGO_GRAVITY_AUTO, or PANGO_GRAVITY_SOUTH if @matrix is %NULL
  *
  * Since: 1.16
  */
@@ -266,11 +266,17 @@ PangoGravity
 pango_matrix_to_gravity (const PangoMatrix *matrix)
 {
   PangoGravity gravity;
-  double x = matrix->xy;
-  double y = matrix->yy;
+  double x;
+  double y;
+  
+  if (!matrix)
+    return PANGO_GRAVITY_SOUTH;
+
+  x = matrix->xy;
+  y = matrix->yy;
 
   if (abs (x) > abs (y))
-    gravity = x < 0 ? PANGO_GRAVITY_WEST : PANGO_GRAVITY_EAST;
+    gravity = x > 0 ? PANGO_GRAVITY_WEST : PANGO_GRAVITY_EAST;
   else
     gravity = y < 0 ? PANGO_GRAVITY_NORTH : PANGO_GRAVITY_SOUTH;
 
diff --git a/pango/pango-types.h b/pango/pango-types.h
index 9d4caba6..2e8b5a83 100644
--- a/pango/pango-types.h
+++ b/pango/pango-types.h
@@ -154,11 +154,16 @@ gboolean       pango_get_mirror_char        (gunichar     ch,
  * @PANGO_GRAVITY_EAST: Glyphs are rotated 90 degrees clockwise
  * @PANGO_GRAVITY_NORTH: Glyphs are upside-down
  * @PANGO_GRAVITY_WEST: Glyphs are rotated 90 degrees counter-clockwise
+ * @PANGO_GRAVITY_AUTO: Gravity is resolved from the context matrix
  * 
  * The #PangoGravity type represents the orientation of glyphs in a segment
  * of text.  This is useful when rendering vertical text layouts.  In
  * those situations, the layout is rotated using a non-identity PangoMatrix,
  * and then glyph orientation is controlled using #PangoGravity.
+ * Not every value in this enumeration makes sense for every usage of
+ * #PangoGravity; for example, %PANGO_GRAVITY_AUTO only can be passed to
+ * pango_context_set_base_gravity() and can only be returned by
+ * pango_context_get_base_gravity().
  *
  * Since: 1.16
  **/			  
@@ -166,7 +171,8 @@ typedef enum {
   PANGO_GRAVITY_SOUTH,
   PANGO_GRAVITY_EAST,
   PANGO_GRAVITY_NORTH,
-  PANGO_GRAVITY_WEST
+  PANGO_GRAVITY_WEST,
+  PANGO_GRAVITY_AUTO
 } PangoGravity;
 
 double pango_gravity_to_rotation (PangoGravity gravity);
diff --git a/pango/pango.def b/pango/pango.def
index 32576db6..fed46d8b 100644
--- a/pango/pango.def
+++ b/pango/pango.def
@@ -54,6 +54,7 @@ EXPORTS
 	pango_context_get_base_gravity
 	pango_context_get_font_description
 	pango_context_get_font_map
+	pango_context_get_gravity
 	pango_context_get_language
 	pango_context_get_matrix
 	pango_context_get_metrics
diff --git a/pango/pangocairo-fcfont.c b/pango/pangocairo-fcfont.c
index a0dec5c6..f6ce1087 100644
--- a/pango/pangocairo-fcfont.c
+++ b/pango/pangocairo-fcfont.c
@@ -239,6 +239,7 @@ pango_cairo_fc_font_get_metrics (PangoFont     *font,
       switch (cffont->gravity)
 	{
 	  default:
+	  case PANGO_GRAVITY_AUTO:
 	  case PANGO_GRAVITY_SOUTH:
 	    break;
 	  case PANGO_GRAVITY_NORTH:
@@ -299,6 +300,7 @@ pango_cairo_fc_font_glyph_extents_cache_init (PangoCairoFcFont *cffont)
   switch (cffont->gravity)
     {
       default:
+      case PANGO_GRAVITY_AUTO:
       case PANGO_GRAVITY_SOUTH:
         cffont->font_extents.y = - PANGO_UNITS (font_extents.ascent);
 	break;
@@ -506,7 +508,7 @@ _pango_cairo_fc_font_new (PangoCairoFcFontMap        *cffontmap,
 			 NULL);
 
   /* FIXME: support per-item gravity */
-  cffont->gravity = pango_context_get_base_gravity (context);
+  cffont->gravity = pango_context_get_gravity (context);
 
   if  (FcPatternGetMatrix (pattern,
 			   FC_MATRIX, 0, &fc_matrix) == FcResultMatch)
diff --git a/pango/pangofc-fontmap.c b/pango/pangofc-fontmap.c
index 356b321a..756774ad 100644
--- a/pango/pangofc-fontmap.c
+++ b/pango/pangofc-fontmap.c
@@ -812,6 +812,7 @@ pango_fc_make_pattern (const  PangoFontDescription *description,
   width = pango_fc_convert_width_to_fc (pango_font_description_get_stretch (description));
 #endif
 
+  /* FIXME: get gravity from description */
   switch (gravity)
     {
       case PANGO_GRAVITY_SOUTH:
@@ -1233,7 +1234,7 @@ pango_fc_font_map_load_fontset (PangoFontMap                 *fontmap,
 {
   /* FIXME: support per-item gravity */
  PangoFcPatternSet *patterns = pango_fc_font_map_get_patterns (fontmap, context, desc, language,
-							       pango_context_get_base_gravity (context));
+							       pango_context_get_gravity (context));
   PangoFontset *result;
   int i;