Add a new context_substitute() virtual function that replaces

2005-05-17  Owen Taylor  <otaylor@redhat.com>

        * pango/pangofc-fontmap.[ch]: Add a new context_substitute() virtual
        function that replaces default_substitute() and adds a
        PangoContext argument.

        * pango/pangocairo.h pango/pangocairo-fontmap.c docs/pango-sections.txt:
        Add pango_cairo_context_set/get_hinting() to control
        hinting on individual contexts.

        * pango/pangocairo-fcfont.c pango/pangocairo-fcfontmap.c:
        Implement hinting control for the for the fontconfig/cairo
        backend.

6 files changed, 92 insertions, 10 deletions

diff --git a/pango/pangocairo-fcfont.c b/pango/pangocairo-fcfont.c
index cde571bf..326cd3e5 100644
--- a/pango/pangocairo-fcfont.c
+++ b/pango/pangocairo-fcfont.c
@@ -341,7 +341,7 @@ _pango_cairo_fc_get_render_key (PangoCairoFcFontMap        *cffontmap,
   *xsize = (int) (xscale * size + 0.5);
   *ysize = (int) (xscale * size + 0.5);
 
-  *flags = 0;
+  *flags = pango_cairo_context_get_hinting (context);
 
   if (matrix)
     {
diff --git a/pango/pangocairo-fcfontmap.c b/pango/pangocairo-fcfontmap.c
index a1a107e9..e032c9d5 100644
--- a/pango/pangocairo-fcfontmap.c
+++ b/pango/pangocairo-fcfontmap.c
@@ -86,7 +86,8 @@ pango_cairo_fc_font_map_finalize (GObject *object)
 }
 
 static void
-pango_cairo_fc_font_map_default_substitute (PangoFcFontMap *fcfontmap,
+pango_cairo_fc_font_map_context_substitute (PangoFcFontMap *fcfontmap,
+					    PangoContext   *context,
 					    FcPattern      *pattern)
 {
   PangoCairoFcFontMap *cffontmap = PANGO_CAIRO_FC_FONT_MAP (fcfontmap);
@@ -96,6 +97,10 @@ pango_cairo_fc_font_map_default_substitute (PangoFcFontMap *fcfontmap,
 
   if (FcPatternGet (pattern, FC_DPI, 0, &v) == FcResultNoMatch)
     FcPatternAddDouble (pattern, FC_DPI, cffontmap->dpi);
+
+  if (!pango_cairo_context_get_hinting (context))
+    FcPatternAddBool (pattern, FC_HINTING, FcFalse);
+  
   FcDefaultSubstitute (pattern);
 }
 
@@ -128,7 +133,7 @@ pango_cairo_fc_font_map_class_init (PangoCairoFcFontMapClass *class)
   PangoFcFontMapClass *fcfontmap_class = PANGO_FC_FONT_MAP_CLASS (class);
 
   gobject_class->finalize  = pango_cairo_fc_font_map_finalize;
-  fcfontmap_class->default_substitute = pango_cairo_fc_font_map_default_substitute;
+  fcfontmap_class->context_substitute = pango_cairo_fc_font_map_context_substitute;
   fcfontmap_class->get_render_key = pango_cairo_fc_font_map_get_render_key;
   fcfontmap_class->create_font = pango_cairo_fc_font_map_create_font;
 }
diff --git a/pango/pangocairo-fontmap.c b/pango/pangocairo-fontmap.c
index f8cd2ab8..5b72375c 100644
--- a/pango/pangocairo-fontmap.c
+++ b/pango/pangocairo-fontmap.c
@@ -226,6 +226,71 @@ pango_cairo_update_context (cairo_t      *cr,
   pango_context_set_matrix (context, &pango_matrix);
 }
 
+typedef struct _PangoCairoContextInfo PangoCairoContextInfo;
+
+struct _PangoCairoContextInfo
+{
+  gboolean hinting;
+};
+
+static PangoCairoContextInfo *
+get_context_info (PangoContext *context,
+		  gboolean      create)
+{
+  PangoCairoContextInfo *info = g_object_get_data (G_OBJECT (context),
+						   "pango-cairo-context-info");
+  if (!info && create)
+    {
+      info = g_new (PangoCairoContextInfo, 1);
+      info->hinting = TRUE;
+
+      g_object_set_data_full (G_OBJECT (context), "pango-cairo-context-info", 
+			      info, (GDestroyNotify)g_free);
+    }
+
+  return info;
+}
+
+/**
+ * pango_cairo_context_set_hinting:
+ * @context: a #PangoContext, from pango_cairo_font_map_create_context()
+ * @hinting: %TRUE if hinting should be enabled.
+ * 
+ * Sets whether outlines and font metrics should be hinted for this
+ * context. Hinting is the process of adjusting outlines so that they
+ * render better when drawn onto a pixel grid. When hinting is
+ * enabled, font metrics such as character widths and font ascent and
+ * descent are quantized to integer pixel values.
+ * 
+ * If layouts have been previously created for this context, it is
+ * necessary to call pango_layout_context_changed() in order to update
+ * the layouts.
+ **/
+void 
+pango_cairo_context_set_hinting (PangoContext *context,
+				 gboolean      hinting)
+{
+  PangoCairoContextInfo *info = get_context_info (context, TRUE);
+  info->hinting = hinting != FALSE;
+}
+
+/**
+ * pango_cairo_context_get_hinting:
+ * @context: a #PangoContext, from pango_cairo_font_map_create_context()
+ * 
+ * Gets whether hinting is enabled for this context. See
+ * pango_cairo_context_set_hinting()
+ * 
+ * Return value: %TRUE if hinting is enabled.
+ **/
+gboolean 
+pango_cairo_context_get_hinting (PangoContext *context)
+{
+  PangoCairoContextInfo *info = get_context_info (context, FALSE);
+
+  return !info || info->hinting;
+}
+
 /**
  * pango_cairo_create_layout:
  * @cr: a Cairo context
diff --git a/pango/pangocairo.h b/pango/pangocairo.h
index 147e619c..ba0949fc 100644
--- a/pango/pangocairo.h
+++ b/pango/pangocairo.h
@@ -62,6 +62,10 @@ PangoContext *pango_cairo_font_map_create_context (PangoCairoFontMap *fontmap);
 void         pango_cairo_update_context (cairo_t      *cr,
 					 PangoContext *context);
 
+void pango_cairo_context_set_hinting (PangoContext *context,
+				      gboolean      hinting);
+gboolean pango_cairo_context_get_hinting (PangoContext *context);
+
 /* Convenience
  */
 PangoLayout *pango_cairo_create_layout (cairo_t     *cr);
diff --git a/pango/pangofc-fontmap.c b/pango/pangofc-fontmap.c
index c4068db3..7804c2e0 100644
--- a/pango/pangofc-fontmap.c
+++ b/pango/pangofc-fontmap.c
@@ -818,14 +818,18 @@ uniquify_pattern (PangoFcFontMap *fcfontmap,
 
 static void
 pango_fc_default_substitute (PangoFcFontMap    *fontmap,
-			     FcPattern          *pattern)
+			     PangoContext      *context,
+			     FcPattern         *pattern)
 {
-  if (PANGO_FC_FONT_MAP_GET_CLASS (fontmap)->default_substitute)
+  if (PANGO_FC_FONT_MAP_GET_CLASS (fontmap)->context_substitute)
+    PANGO_FC_FONT_MAP_GET_CLASS (fontmap)->context_substitute (fontmap, context, pattern);
+  else if (PANGO_FC_FONT_MAP_GET_CLASS (fontmap)->default_substitute)
     PANGO_FC_FONT_MAP_GET_CLASS (fontmap)->default_substitute (fontmap, pattern);
 }
 
 static gdouble
-pango_fc_font_map_get_dpi (PangoFcFontMap *fcfontmap)
+pango_fc_font_map_get_dpi (PangoFcFontMap *fcfontmap,
+			   PangoContext   *context)
 {
   if (fcfontmap->priv->dpi < 0)
     {
@@ -836,7 +840,7 @@ pango_fc_font_map_get_dpi (PangoFcFontMap *fcfontmap)
 				       NULL);
       if (tmp)
 	{
-	  pango_fc_default_substitute (fcfontmap, tmp);
+	  pango_fc_default_substitute (fcfontmap, NULL, tmp);
 	  result = FcPatternGetDouble (tmp, FC_DPI, 0, &fcfontmap->priv->dpi);
 	  FcPatternDestroy (tmp);
 	}
@@ -881,7 +885,7 @@ pango_fc_font_map_get_render_key (PangoFcFontMap              *fcfontmap,
       if (pango_font_description_get_size_is_absolute (desc))
 	size = pango_font_description_get_size (desc);
       else
-	size = pango_fc_font_map_get_dpi (fcfontmap) * pango_font_description_get_size (desc) / 72.;
+	size = pango_fc_font_map_get_dpi (fcfontmap, context) * pango_font_description_get_size (desc) / 72.;
       
       if (context)
 	matrix = pango_context_get_matrix (context);
@@ -947,7 +951,7 @@ pango_fc_font_map_get_patterns (PangoFontMap               *fontmap,
     {
       pattern = pango_fc_make_pattern (desc, language, key.y_size / 1024.);
 
-      pango_fc_default_substitute (fcfontmap, pattern);
+      pango_fc_default_substitute (fcfontmap, context, pattern);
       
       font_patterns = FcFontSort (NULL, pattern, FcTrue, NULL, &res);
 
@@ -1609,7 +1613,7 @@ pango_fc_face_list_sizes (PangoFontFace  *face,
           if (FcPatternGetDouble (fontset->fonts[i], FC_PIXEL_SIZE, 0, &size) == FcResultMatch)
             {
               if (dpi < 0)
-		dpi = pango_fc_font_map_get_dpi (fcface->family->fontmap);
+		dpi = pango_fc_font_map_get_dpi (fcface->family->fontmap, NULL);
 	      
               size_i = (int) (PANGO_SCALE * size * 72.0 / dpi);
               g_array_append_val (size_array, size_i);
diff --git a/pango/pangofc-fontmap.h b/pango/pangofc-fontmap.h
index 4e98bc78..a6f4d511 100644
--- a/pango/pangofc-fontmap.h
+++ b/pango/pangofc-fontmap.h
@@ -89,6 +89,7 @@ struct _PangoFcFontMapClass
   PangoFontMapClass parent_class;
 
   /*< public >*/
+  /* Deprecated in favor of context_substitute */
   void         (*default_substitute) (PangoFcFontMap   *fontmap,
 			              FcPattern        *pattern);
   /* Deprecated in favor of create_font */
@@ -101,6 +102,9 @@ struct _PangoFcFontMapClass
 				      int                        *xsize,
 				      int                        *ysize,
 				      guint                      *flags);
+  void         (*context_substitute) (PangoFcFontMap             *fontmap,
+				      PangoContext               *context,
+			              FcPattern                  *pattern);
   PangoFcFont  *(*create_font)       (PangoFcFontMap             *fontmap,
 				      PangoContext               *context,
 				      const PangoFontDescription *desc,