[pango/small-caps: 1/2] Reshuffle itemize API

[Matthias Clasen <matthiasc src gnome org>]

commit b9b92e79da0e55acf0c13968ca699d4dd78fc614
Author: Matthias Clasen <mclasen redhat com>
Date:   Sun Nov 7 11:11:45 2021 -0500

    Reshuffle itemize API
    
    Split the post-processing off into a separate function
    that can take log attrs in addition. This will allow
    us to handle word starts when dealing with text transforms
    for emulated Small Caps.
    
    So far, this is all private API that is used from PangoLayout.
    Please file an issue if you want to access Small Caps emulation
    without PangoLayout.

 pango/itemize.c            | 64 +++++++++++++++++++++++++++++-----------------
 pango/pango-item-private.h |  6 +++++
 pango/pango-layout.c       | 20 ++++++++++-----
 3 files changed, 59 insertions(+), 31 deletions(-)
---
diff --git a/pango/itemize.c b/pango/itemize.c
index e39e6fe2..b5f544a7 100644
--- a/pango/itemize.c
+++ b/pango/itemize.c
@@ -1435,26 +1435,30 @@ handle_variants (const char *text,
 /* }}} */
 
 static GList *
-post_process_items (PangoContext *context,
-                    const char   *text,
-                    GList        *items)
+reorder_items (PangoContext *context,
+               GList        *items)
 {
+  int char_offset = 0;
+
   items = g_list_reverse (items);
 
-  /* Compute the char offset for each item */
-  {
-    int char_offset = 0;
-    for (GList *l = items; l; l = l->next)
-      {
-        PangoItemPrivate *item = l->data;
-        item->char_offset = char_offset;
-        char_offset += item->num_chars;
-      }
-  }
+  /* Also cmpute the char offset for each item here */
+  for (GList *l = items; l; l = l->next)
+    {
+      PangoItemPrivate *item = l->data;
+      item->char_offset = char_offset;
+      char_offset += item->num_chars;
+    }
 
-  handle_variants (text, items);
+  return items;
+}
 
-  /* apply font-scale */
+static GList *
+post_process_items (PangoContext *context,
+                    const char   *text,
+                    GList        *items)
+{
+  handle_variants (text, items);
   apply_font_scale (context, items);
 
   return items;
@@ -1488,7 +1492,16 @@ pango_itemize_with_font (PangoContext               *context,
 
   itemize_state_finish (&state);
 
-  return post_process_items (context, text, state.result);
+  return reorder_items (context, state.result);
+}
+
+GList *
+pango_itemize_post_process_items (PangoContext *context,
+                                  const char   *text,
+                                  PangoLogAttr *log_attrs,
+                                  GList        *items)
+{
+  return post_process_items (context, text, items);
 }
 
 /* }}} */
@@ -1527,15 +1540,19 @@ pango_itemize_with_base_dir (PangoContext      *context,
                              PangoAttrList     *attrs,
                              PangoAttrIterator *cached_iter)
 {
+  GList *items;
+
   g_return_val_if_fail (context != NULL, NULL);
   g_return_val_if_fail (start_index >= 0, NULL);
   g_return_val_if_fail (length >= 0, NULL);
   g_return_val_if_fail (length == 0 || text != NULL, NULL);
 
-  return pango_itemize_with_font (context, base_dir,
-                                  text, start_index, length,
-                                  attrs, cached_iter,
-                                  NULL);
+  items = pango_itemize_with_font (context, base_dir,
+                                   text, start_index, length,
+                                   attrs, cached_iter,
+                                   NULL);
+
+  return pango_itemize_post_process_items (context, text, NULL, items);
 }
 
 /**
@@ -1579,10 +1596,9 @@ pango_itemize (PangoContext      *context,
   g_return_val_if_fail (length >= 0, NULL);
   g_return_val_if_fail (length == 0 || text != NULL, NULL);
 
-  return pango_itemize_with_font (context, context->base_dir,
-                                  text, start_index, length,
-                                  attrs, cached_iter,
-                                  NULL);
+  return pango_itemize_with_base_dir (context, context->base_dir,
+                                      text, start_index, length,
+                                      attrs, cached_iter);
 }
 
  /* }}} */
diff --git a/pango/pango-item-private.h b/pango/pango-item-private.h
index e80a3c02..ef3e8ed0 100644
--- a/pango/pango-item-private.h
+++ b/pango/pango-item-private.h
@@ -22,6 +22,7 @@
 #define __PANGO_ITEM_PRIVATE_H__
 
 #include <pango/pango-item.h>
+#include <pango/pango-break.h>
 
 G_BEGIN_DECLS
 
@@ -82,6 +83,11 @@ GList *            pango_itemize_with_font            (PangoContext
                                                        PangoAttrIterator          *cached_iter,
                                                        const PangoFontDescription *desc);
 
+GList *            pango_itemize_post_process_items   (PangoContext               *context,
+                                                       const char                 *text,
+                                                       PangoLogAttr               *log_attrs,
+                                                       GList                      *items);
+
 
 G_END_DECLS
 
diff --git a/pango/pango-layout.c b/pango/pango-layout.c
index ba81adf6..9e8ce248 100644
--- a/pango/pango-layout.c
+++ b/pango/pango-layout.c
@@ -4534,13 +4534,14 @@ pango_layout_check_lines (PangoLayout *layout)
       g_assert (delim_len >= 0);
 
       state.attrs = itemize_attrs;
-      state.items = pango_itemize_with_base_dir (layout->context,
-                                                 base_dir,
-                                                 layout->text,
-                                                 start - layout->text,
-                                                 end - start,
-                                                 itemize_attrs,
-                                                 itemize_attrs ? &iter : NULL);
+      state.items = pango_itemize_with_font (layout->context,
+                                             base_dir,
+                                             layout->text,
+                                             start - layout->text,
+                                             end - start,
+                                             itemize_attrs,
+                                             itemize_attrs ? &iter : NULL,
+                                             NULL);
 
       apply_attributes_to_items (state.items, shape_attrs);
 
@@ -4553,6 +4554,11 @@ pango_layout_check_lines (PangoLayout *layout)
                              layout->log_attrs + start_offset,
                              layout->n_chars + 1 - start_offset);
 
+      state.items = pango_itemize_post_process_items (layout->context,
+                                                      layout->text,
+                                                      layout->log_attrs + start_offset,
+                                                      state.items);
+
       state.base_dir = base_dir;
       state.line_of_par = 1;
       state.start_offset = start_offset;