Bug 337593 – move glyph extents code (and cache) from pangocairo-*font.c

2007-06-09  Behdad Esfahbod  <behdad@gnome.org>

        Bug 337593 – move glyph extents code (and cache) from
        pangocairo-*font.c into pangocairo-font.c

        * pango/pangocairo-fontmap.c:
        * pango/pangocairo-fcfontmap.c:
        Remove per-fontmap renderer.  We've not been using it for a while
        and there is no reason to use it.

        * pango/pangocairo-font.c
        * pango/pangocairo-fcfont.c: 
        Most most code (including glyph extents caching) from fcfont.c to 
        font.c.  Simplifies individual backends a lot. ATSUI and Win32 
        cairo backends should adapt.

        * pango/pangocairo-render.c
        * pango/pangocairo-private.h:
        Update to reflect above changes.


svn path=/trunk/; revision=2335

1 files changed, 56 insertions, 369 deletions

diff --git a/pango/pangocairo-fcfont.c b/pango/pangocairo-fcfont.c
index 8c44b2a0..b671ebea 100644
--- a/pango/pangocairo-fcfont.c
+++ b/pango/pangocairo-fcfont.c
@@ -21,9 +21,6 @@
 
 #include <config.h>
 
-#include <math.h>
-#include <stdlib.h>
-
 #include <cairo-ft.h>
 
 #include "pango-fontmap.h"
@@ -41,36 +38,12 @@
 typedef struct _PangoCairoFcFont      PangoCairoFcFont;
 typedef struct _PangoCairoFcFontClass PangoCairoFcFontClass;
 
-typedef struct _GlyphExtentsCacheEntry    GlyphExtentsCacheEntry;
-
-#define GLYPH_CACHE_NUM_ENTRIES 256 /* should be power of two */
-#define GLYPH_CACHE_MASK (GLYPH_CACHE_NUM_ENTRIES - 1)
-
-/* An entry in the fixed-size cache for the glyph -> ink_rect mapping.
- * The cache is indexed by the lower N bits of the glyph (see
- * GLYPH_CACHE_NUM_ENTRIES).  For scripts with few glyphs,
- * this should provide pretty much instant lookups.
- */
-struct _GlyphExtentsCacheEntry
-{
-  PangoGlyph     glyph;
-  int            width;
-  PangoRectangle ink_rect;
-};
-
 struct _PangoCairoFcFont
 {
   PangoFcFont font;
+  PangoCairoFontPrivate cf_priv;
 
-  cairo_font_face_t *font_face;
-  cairo_scaled_font_t *scaled_font;
-  cairo_matrix_t font_matrix;
-  cairo_matrix_t ctm;
-  cairo_font_options_t *options;
   PangoGravity gravity;
-
-  PangoRectangle font_extents;
-  GlyphExtentsCacheEntry    *glyph_extents_cache;
 };
 
 struct _PangoCairoFcFontClass
@@ -80,86 +53,33 @@ struct _PangoCairoFcFontClass
 
 GType pango_cairo_fc_font_get_type (void);
 
-static cairo_font_face_t *pango_cairo_fc_font_get_font_face (PangoCairoFont *font);
-
-/*******************************
- *       Utility functions     *
- *******************************/
+/********************************
+ *    Method implementations    *
+ ********************************/
 
 static cairo_font_face_t *
-pango_cairo_fc_font_get_font_face (PangoCairoFont *font)
-{
-  PangoCairoFcFont *cffont = (PangoCairoFcFont *) (font);
-  PangoFcFont *fcfont = (PangoFcFont *) (cffont);
-
-  if (!cffont->font_face)
-    {
-      cffont->font_face = cairo_ft_font_face_create_for_pattern (fcfont->font_pattern);
-
-      /* Unable to create FT2 cairo scaled font.
-       * This means out of memory or a cairo/fontconfig/FreeType bug,
-       */
-      if (!cffont->font_face)
-	return NULL;
-    }
-
-  return cffont->font_face;
-}
-
-static cairo_scaled_font_t *
-pango_cairo_fc_font_get_scaled_font (PangoCairoFont *font)
+pango_cairo_fc_font_create_font_face (PangoCairoFont *cfont)
 {
-  PangoCairoFcFont *cffont = (PangoCairoFcFont *)font;
+  PangoFcFont *fcfont = (PangoFcFont *) (cfont);
 
-  if (!cffont->scaled_font)
-    {
-      cairo_font_face_t *font_face;
-
-      font_face = pango_cairo_fc_font_get_font_face (font);
-
-      if (!font_face)
-	return NULL;
-
-      cffont->scaled_font = cairo_scaled_font_create (font_face,
-						      &cffont->font_matrix,
-						      &cffont->ctm,
-						      cffont->options);
-
-      /* Unable to create FT2 cairo scaled font.
-       * This means out of memory or a cairo/fontconfig/FreeType bug,
-       * or a missing font...
-       */
-      if (!cffont->scaled_font)
-	return NULL;
-    }
-
-  return cffont->scaled_font;
+  return cairo_ft_font_face_create_for_pattern (fcfont->font_pattern);
 }
 
-/********************************
- *    Method implementations    *
- ********************************/
-
-static gboolean
-pango_cairo_fc_font_install (PangoCairoFont *font,
-			     cairo_t        *cr)
+static PangoFontMetrics *
+pango_cairo_fc_font_create_metrics_for_context (PangoCairoFont *cfont,
+					        PangoContext   *context)
 {
-  PangoCairoFcFont *cffont = (PangoCairoFcFont *) (font);
-
-  cairo_set_font_face (cr,
-		       pango_cairo_fc_font_get_font_face (font));
-  cairo_set_font_matrix (cr, &cffont->font_matrix);
-  cairo_set_font_options (cr, cffont->options);
+  PangoFcFont *fcfont = (PangoFcFont *) (cfont);
 
-  return TRUE;
+  return pango_fc_font_create_metrics_for_context (fcfont, context);
 }
 
 static void
 cairo_font_iface_init (PangoCairoFontIface *iface)
 {
-  iface->install = pango_cairo_fc_font_install;
-  iface->get_font_face = pango_cairo_fc_font_get_font_face;
-  iface->get_scaled_font = pango_cairo_fc_font_get_scaled_font;
+  iface->create_font_face = pango_cairo_fc_font_create_font_face;
+  iface->create_metrics_for_context = pango_cairo_fc_font_create_metrics_for_context;
+  iface->cf_priv_offset = G_STRUCT_OFFSET (PangoCairoFcFont, cf_priv);
 }
 
 G_DEFINE_TYPE_WITH_CODE (PangoCairoFcFont, pango_cairo_fc_font, PANGO_TYPE_FC_FONT,
@@ -170,105 +90,34 @@ pango_cairo_fc_font_finalize (GObject *object)
 {
   PangoCairoFcFont *cffont = (PangoCairoFcFont *) (object);
 
-  if (cffont->font_face)
-    cairo_font_face_destroy (cffont->font_face);
-  if (cffont->scaled_font)
-    cairo_scaled_font_destroy (cffont->scaled_font);
-  if (cffont->options)
-    cairo_font_options_destroy (cffont->options);
-
-
-  if (cffont->glyph_extents_cache)
-    {
-      g_free (cffont->glyph_extents_cache);
-    }
+  _pango_cairo_font_private_finalize (&cffont->cf_priv);
 
   G_OBJECT_CLASS (pango_cairo_fc_font_parent_class)->finalize (object);
 }
 
-/* This function is cut-and-pasted from pangocairo-fcfont.c - it might be
- * better to add a virtual fcfont->create_context (font).
- */
-static PangoFontMetrics *
-pango_cairo_fc_font_get_metrics (PangoFont     *font,
-				 PangoLanguage *language)
+/* we want get_glyph_extents extremely fast, so we use a small wrapper here
+ * to avoid having to lookup the interface data like we do for get_metrics
+ * in _pango_cairo_font_get_metrics(). */
+static void
+pango_cairo_fc_font_get_glyph_extents (PangoFont      *font,
+				       PangoGlyph      glyph,
+				       PangoRectangle *ink_rect,
+				       PangoRectangle *logical_rect)
 {
-  PangoFcFont *fcfont = (PangoFcFont *) (font);
   PangoCairoFcFont *cffont = (PangoCairoFcFont *) (font);
-  PangoFcMetricsInfo *info = NULL; /* Quiet gcc */
-  GSList *tmp_list;
-
-  const char *sample_str = pango_language_get_sample_string (language);
-
-  tmp_list = fcfont->metrics_by_lang;
-  while (tmp_list)
-    {
-      info = tmp_list->data;
-
-      if (info->sample_str == sample_str)    /* We _don't_ need strcmp */
-	break;
-
-      tmp_list = tmp_list->next;
-    }
 
-  if (!tmp_list)
-    {
-      PangoContext *context;
-      int height, shift;
-
-      if (!fcfont->fontmap)
-	return pango_font_metrics_new ();
-
-      info = g_slice_new0 (PangoFcMetricsInfo);
-
-      fcfont->metrics_by_lang = g_slist_prepend (fcfont->metrics_by_lang, info);
-
-      info->sample_str = sample_str;
-
-      context = pango_fc_font_map_create_context (PANGO_FC_FONT_MAP (fcfont->fontmap));
-      pango_context_set_language (context, language);
-      pango_cairo_context_set_font_options (context, cffont->options);
-
-      info->metrics = pango_fc_font_create_metrics_for_context (fcfont, context);
-      /* We may actually reuse ascent/descent we got from cairo here.  that's
-       * in cffont->font_extents.
-       */
-      height = info->metrics->ascent + info->metrics->descent;
-      switch (cffont->gravity)
-	{
-	  default:
-	  case PANGO_GRAVITY_AUTO:
-	  case PANGO_GRAVITY_SOUTH:
-	    break;
-	  case PANGO_GRAVITY_NORTH:
-	    info->metrics->ascent = info->metrics->descent;
-	    break;
-	  case PANGO_GRAVITY_EAST:
-	  case PANGO_GRAVITY_WEST:
-	    {
-	      int ascent = height / 2;
-	      if (fcfont->is_hinted)
-	        ascent = PANGO_UNITS_ROUND (ascent);
-	      info->metrics->ascent = ascent;
-	    }
-	}
-      shift = (height - info->metrics->ascent) - info->metrics->descent;
-      info->metrics->descent += shift;
-      info->metrics->underline_position -= shift;
-      info->metrics->strikethrough_position -= shift;
-      info->metrics->ascent = height - info->metrics->descent;
-
-      g_object_unref (context);
-    }
-
-  return pango_font_metrics_ref (info->metrics);
+  _pango_cairo_font_private_get_glyph_extents (&cffont->cf_priv,
+					       glyph,
+					       ink_rect,
+					       logical_rect);
 }
 
 static FT_Face
 pango_cairo_fc_font_lock_face (PangoFcFont *font)
 {
-  PangoCairoFont *cfont = (PangoCairoFont *)font;
-  cairo_scaled_font_t *scaled_font = pango_cairo_fc_font_get_scaled_font (cfont);
+  PangoCairoFcFont *cffont = (PangoCairoFcFont *) (font);
+  cairo_scaled_font_t *scaled_font = _pango_cairo_font_private_get_scaled_font (&cffont->cf_priv);
+
   if (G_UNLIKELY (!scaled_font))
     return NULL;
 
@@ -278,8 +127,9 @@ pango_cairo_fc_font_lock_face (PangoFcFont *font)
 static void
 pango_cairo_fc_font_unlock_face (PangoFcFont *font)
 {
-  PangoCairoFont *cfont = (PangoCairoFont *)font;
-  cairo_scaled_font_t *scaled_font = pango_cairo_fc_font_get_scaled_font (cfont);
+  PangoCairoFcFont *cffont = (PangoCairoFcFont *) (font);
+  cairo_scaled_font_t *scaled_font = _pango_cairo_font_private_get_scaled_font (&cffont->cf_priv);
+
   if (G_UNLIKELY (!scaled_font))
     return;
 
@@ -287,146 +137,11 @@ pango_cairo_fc_font_unlock_face (PangoFcFont *font)
 }
 
 static void
-pango_cairo_fc_font_glyph_extents_cache_init (PangoCairoFcFont *cffont)
-{
-  PangoCairoFont *cfont = (PangoCairoFont *)cffont;
-  cairo_scaled_font_t *scaled_font = pango_cairo_fc_font_get_scaled_font (cfont);
-  cairo_font_extents_t font_extents;
-
-  cairo_scaled_font_extents (scaled_font, &font_extents);
-
-  cffont->font_extents.x = 0;
-  cffont->font_extents.width = 0;
-  cffont->font_extents.height = pango_units_from_double (font_extents.ascent + font_extents.descent);
-  switch (cffont->gravity)
-    {
-      default:
-      case PANGO_GRAVITY_AUTO:
-      case PANGO_GRAVITY_SOUTH:
-	cffont->font_extents.y = - pango_units_from_double (font_extents.ascent);
-	break;
-      case PANGO_GRAVITY_NORTH:
-	cffont->font_extents.y = - pango_units_from_double (font_extents.descent);
-	break;
-      case PANGO_GRAVITY_EAST:
-      case PANGO_GRAVITY_WEST:
-	{
-	  PangoFcFont *fcfont = (PangoFcFont *) (cffont);
-	  int ascent = pango_units_from_double (font_extents.ascent + font_extents.descent) / 2;
-	  if (fcfont->is_hinted)
-	    ascent = PANGO_UNITS_ROUND (ascent);
-	  cffont->font_extents.y = - ascent;
-	}
-    }
-
-  cffont->glyph_extents_cache = g_new0 (GlyphExtentsCacheEntry, GLYPH_CACHE_NUM_ENTRIES);
-  /* Make sure all cache entries are invalid initially */
-  cffont->glyph_extents_cache[0].glyph = 1; /* glyph 1 cannot happen in bucket 0 */
-}
-
-/* Fills in the glyph extents cache entry
- */
-static void
-compute_glyph_extents (PangoCairoFcFont       *cffont,
-		       PangoGlyph              glyph,
-		       GlyphExtentsCacheEntry *entry)
-{
-  cairo_text_extents_t extents;
-  cairo_glyph_t cairo_glyph;
-
-  cairo_glyph.index = glyph;
-  cairo_glyph.x = 0;
-  cairo_glyph.y = 0;
-
-  cairo_scaled_font_glyph_extents (cffont->scaled_font,
-				   &cairo_glyph, 1, &extents);
-
-  entry->glyph = glyph;
-  entry->width = pango_units_from_double (extents.x_advance);
-  entry->ink_rect.x = pango_units_from_double (extents.x_bearing);
-  entry->ink_rect.y = pango_units_from_double (extents.y_bearing);
-  entry->ink_rect.width = pango_units_from_double (extents.width);
-  entry->ink_rect.height = pango_units_from_double (extents.height);
-}
-
-static GlyphExtentsCacheEntry *
-pango_cairo_fc_font_get_glyph_extents_cache_entry (PangoCairoFcFont       *cffont,
-						   PangoGlyph              glyph)
-{
-  GlyphExtentsCacheEntry *entry;
-  guint idx;
-
-  idx = glyph & GLYPH_CACHE_MASK;
-  entry = cffont->glyph_extents_cache + idx;
-
-  if (entry->glyph != glyph)
-    {
-      compute_glyph_extents (cffont, glyph, entry);
-    }
-
-  return entry;
-}
-
-static void
-pango_cairo_fc_font_get_glyph_extents (PangoFont      *font,
-				       PangoGlyph      glyph,
-				       PangoRectangle *ink_rect,
-				       PangoRectangle *logical_rect)
-{
-  PangoCairoFcFont *cffont = (PangoCairoFcFont *)font;
-  GlyphExtentsCacheEntry *entry;
-
-  if (!pango_cairo_fc_font_get_scaled_font ((PangoCairoFont *)cffont))
-    {
-      /* Get generic unknown-glyph extents. */
-      pango_font_get_glyph_extents (NULL, glyph, ink_rect, logical_rect);
-      return;
-    }
-
-  /* We need to initialize the cache here, since we use cffont->font_extents
-   */
-  if (cffont->glyph_extents_cache == NULL)
-    pango_cairo_fc_font_glyph_extents_cache_init (cffont);
-
-  if (glyph == PANGO_GLYPH_EMPTY)
-    {
-      if (ink_rect)
-	ink_rect->x = ink_rect->y = ink_rect->width = ink_rect->height = 0;
-      if (logical_rect)
-	*logical_rect = cffont->font_extents;
-      return;
-    }
-  else if (glyph & PANGO_GLYPH_UNKNOWN_FLAG)
-    {
-      _pango_cairo_get_glyph_extents_missing((PangoCairoFont *)font, glyph, ink_rect, logical_rect);
-      return;
-    }
-
-  entry = pango_cairo_fc_font_get_glyph_extents_cache_entry (cffont, glyph);
-
-  if (ink_rect)
-    *ink_rect = entry->ink_rect;
-  if (logical_rect)
-    {
-      *logical_rect = cffont->font_extents;
-      logical_rect->width = entry->width;
-    }
-}
-
-static void
 pango_cairo_fc_font_shutdown (PangoFcFont *fcfont)
 {
   PangoCairoFcFont *cffont = (PangoCairoFcFont *) (fcfont);
-  if (cffont->scaled_font)
-    {
-      cairo_scaled_font_destroy (cffont->scaled_font);
-      cffont->scaled_font = NULL;
-    }
-  if (cffont->font_face)
-    {
-      cairo_font_face_destroy (cffont->font_face);
-      cffont->font_face = NULL;
-    }
+
+  _pango_cairo_font_private_finalize (&cffont->cf_priv);
 }
 
 static void
@@ -439,7 +154,7 @@ pango_cairo_fc_font_class_init (PangoCairoFcFontClass *class)
   object_class->finalize = pango_cairo_fc_font_finalize;
 
   font_class->get_glyph_extents = pango_cairo_fc_font_get_glyph_extents;
-  font_class->get_metrics = pango_cairo_fc_font_get_metrics;
+  font_class->get_metrics = _pango_cairo_font_get_metrics;
 
   fc_font_class->lock_face = pango_cairo_fc_font_lock_face;
   fc_font_class->unlock_face = pango_cairo_fc_font_unlock_face;
@@ -459,8 +174,7 @@ static double
 get_font_size (PangoCairoFcFontMap        *cffontmap,
 	       PangoContext               *context,
 	       const PangoFontDescription *desc,
-	       FcPattern                  *pattern,
-	       const PangoMatrix          *matrix)
+	       FcPattern                  *pattern)
 {
   double size;
 
@@ -478,7 +192,7 @@ get_font_size (PangoCairoFcFontMap        *cffontmap,
   */
 
   if (FcPatternGetDouble (pattern, FC_PIXEL_SIZE, 0, &size) == FcResultMatch)
-    return size * PANGO_SCALE / pango_matrix_get_font_scale_factor (matrix);
+    return size * PANGO_SCALE / pango_matrix_get_font_scale_factor (pango_context_get_matrix (context));
 
   /* Just in case FC_PIXEL_SIZE got unset between pango_fc_make_pattern()
    * and here.
@@ -503,7 +217,7 @@ _pango_cairo_fc_font_new (PangoCairoFcFontMap        *cffontmap,
 			  FcPattern	             *pattern)
 {
   PangoCairoFcFont *cffont;
-  const PangoMatrix *pango_ctm;
+  cairo_matrix_t font_matrix;
   FcMatrix *fc_matrix;
   double size;
 
@@ -514,56 +228,29 @@ _pango_cairo_fc_font_new (PangoCairoFcFontMap        *cffontmap,
 			 "pattern", pattern,
 			 NULL);
 
-  cffont->gravity = pango_font_description_get_gravity (desc);
-
-  /* first apply gravity rotation, then pattern matrix, such that
-   * vertical italic text comes out "correct".  we don't do anything
-   * like baseline adjustment etc though.  should be specially
-   * handled when we support italic correction. */
-  cairo_matrix_init_rotate(&cffont->font_matrix,
-			  pango_gravity_to_rotation (cffont->gravity));
+  size = get_font_size (cffontmap, context, desc, pattern);
 
   if  (FcPatternGetMatrix (pattern,
 			   FC_MATRIX, 0, &fc_matrix) == FcResultMatch)
-    {
-      cairo_matrix_t matrix;
-
-      cairo_matrix_init (&matrix,
-			 fc_matrix->xx,
-			 - fc_matrix->yx,
-			 - fc_matrix->xy,
-			 fc_matrix->yy,
-			 0., 0.);
-
-      cairo_matrix_multiply (&cffont->font_matrix,
-			     &matrix,
-			     &cffont->font_matrix);
-    }
-
-  pango_ctm = pango_context_get_matrix (context);
-
-  size = get_font_size (cffontmap, context, desc, pattern, pango_ctm);
-
-  cairo_matrix_scale (&cffont->font_matrix,
-		      size / PANGO_SCALE, size / PANGO_SCALE);
-
-  if (pango_ctm)
-    cairo_matrix_init (&cffont->ctm,
-		       pango_ctm->xx,
-		       pango_ctm->yx,
-		       pango_ctm->xy,
-		       pango_ctm->yy,
+    cairo_matrix_init (&font_matrix,
+		       fc_matrix->xx,
+		       - fc_matrix->yx,
+		       - fc_matrix->xy,
+		       fc_matrix->yy,
 		       0., 0.);
   else
-    cairo_matrix_init_identity (&cffont->ctm);
+    cairo_matrix_init_identity (&font_matrix);
 
+  cairo_matrix_scale (&font_matrix,
+		      size / PANGO_SCALE, size / PANGO_SCALE);
 
-  cffont->options = cairo_font_options_copy (_pango_cairo_context_get_merged_font_options (context));
+  _pango_cairo_font_private_initialize (&cffont->cf_priv,
+					(PangoCairoFont *) cffont,
+					context,
+					desc,
+					&font_matrix);
 
-  /* fcfont's is_hinted controls metric hinting
-   */
-  ((PangoFcFont *)(cffont))->is_hinted =
-    (cairo_font_options_get_hint_metrics(cffont->options) != CAIRO_HINT_METRICS_OFF);
+  ((PangoFcFont *)(cffont))->is_hinted = _pango_cairo_font_private_is_metrics_hinted (&cffont->cf_priv);
 
-  return (PangoFcFont *) (cffont);
+  return (PangoFcFont *) cffont;
 }