Extend CID service functions to handle CID-keyed CFFs as CID fonts.

ChangeLog

@@ -1,3 +1,32 @@
+2009-03-11  Michael Toftdal  <toftdal@gmail.com>
+
+	Extend CID service functions to handle CID-keyed CFFs as CID fonts.
+
+	* include/freetype/ftcid.h (FT_Get_CID_Is_Internally_CID_keyed,
+	FT_Get_CID_From_Glyph_Index): New functions.
+
+	* include/freetype/internal/services/svcid.h
+	(FT_CID_GetIsInternallyCIDKeyedFunc,
+	FT_CID_GetCIDFromGlyphIndexFunc): New function typedefs.
+	(CID Service): Use them.
+
+	* src/base/ftcid.c: Include FT_CID_H.
+	(FT_Get_CID_Is_Internally_CID_keyed, FT_Get_CID_From_Glyph_Index):
+	New functions.
+
+	* src/cff/cffdrivr.c (cff_get_is_cid, cff_get_cid_from_glyph_index):
+	New functions.
+	(cff_service_cid_info): Add them.
+	* src/cff/cffload.c (cff_font_load): Don't free `font->charset.sids'
+	-- it is needed for access as a CID-keyed font.  It gets deleted
+	later on.
+
+	* src/cid/cidriver.c (cid_get_is_cid, cid_get_cid_from_glyph_index):
+	New functions.
+	(cid_service_cid_info): Add them.
+
+	* docs/CHANGES: Updated.
+
 2009-03-11  Bram Tassyns  <bramt@enfocus.be>
 
 	Fix Savannah bug #25597.

docs/CHANGES

@@ -39,7 +39,15 @@ CHANGES BETWEEN 2.3.9 and 2.3.8
     - Composite SFNT bitmaps are now handled correctly.
 
 
-  II. MISCELLANEOUS
+  II. IMPORTANT CHANGES
+
+    - The   new  functions   `FT_Get_CID_Is_Internally_CID_keyed'  and
+      `FT_Get_CID_From_Glyph_Index'  can be  used to  access CID-keyed
+      CFF fonts  via CID  values.  This code  has been  contributed by
+      Michael Toftdal.
+
+
+  III. MISCELLANEOUS
 
     - `FT_Outline_Get_InsideBorder'  returns   FT_STROKER_BORDER_RIGHT
       for empty outlines.  This was incorrectly documented.

include/freetype/ftcid.h

@@ -4,7 +4,7 @@
 /*                                                                         */
 /*    FreeType API for accessing CID font information (specification).     */
 /*                                                                         */
-/*  Copyright 2007 by Dereg Clegg.                                         */
+/*  Copyright 2007, 2009 by Dereg Clegg, Michael Toftdal.                  */
 /*                                                                         */
 /*  This file is part of the FreeType project, and may only be used,       */
 /*  modified, and distributed under the terms of the FreeType project      */
@@ -88,6 +88,74 @@ FT_BEGIN_HEADER
                                            const char*  *ordering,
                                            FT_Int       *supplement);
 
+
+  /**********************************************************************
+   *
+   * @function:
+   *    FT_Get_CID_Is_Internally_CID_Keyed
+   *
+   * @description:
+   *    Retrieve the type of the input face, CID keyed or not.  In
+   *    constrast to the @FT_IS_CID_KEYED macro this function returns
+   *    successfully also for CID-keyed fonts in an SNFT wrapper.
+   *
+   * @input:
+   *    face ::
+   *       A handle to the input face.
+   *
+   * @output:
+   *    is_cid ::
+   *       The type of the face as an @FT_Bool.
+   *
+   * @return:
+   *    FreeType error code.  0~means success.
+   *
+   * @note:
+   *    This function only works with CID faces and OpenType fonts,
+   *    returning an error otherwise.
+   *
+   * @since:
+   *    2.3.9
+   */
+  FT_EXPORT( FT_Error )
+  FT_Get_CID_Is_Internally_CID_Keyed( FT_Face   face,
+                                      FT_Bool  *is_cid );
+
+
+  /**********************************************************************
+   *
+   * @function:
+   *    FT_Get_CID_From_Glyph_Index
+   *
+   * @description:
+   *    Retrieve the CID of the input glyph index.
+   *
+   * @input:
+   *    face ::
+   *       A handle to the input face.
+   *
+   *    glyph_index ::
+   *       The input glyph index.
+   *
+   * @output:
+   *    cid ::
+   *       The CID as an FT_UInt.
+   *
+   * @return:
+   *    FreeType error code.  0~means success.
+   *
+   * @note:
+   *    This function only works with CID faces and OpenType fonts,
+   *    returning an error otherwise.
+   *
+   * @since:
+   *    2.3.9
+   */
+  FT_EXPORT( FT_Error )
+  FT_Get_CID_From_Glyph_Index( FT_Face   face,
+                               FT_UInt   glyph_index,
+                               FT_UInt  *cid );
+
  /* */
 
 FT_END_HEADER

include/freetype/internal/services/svcid.h

@@ -4,7 +4,7 @@
 /*                                                                         */
 /*    The FreeType CID font services (specification).                      */
 /*                                                                         */
-/*  Copyright 2007 by Derek Clegg.                                         */
+/*  Copyright 2007, 2009 by Derek Clegg, Michael Toftdal.                  */
 /*                                                                         */
 /*  This file is part of the FreeType project, and may only be used,       */
 /*  modified, and distributed under the terms of the FreeType project      */
@@ -31,10 +31,19 @@ FT_BEGIN_HEADER
                                                const char*  *registry,
                                                const char*  *ordering,
                                                FT_Int       *supplement );
+  typedef FT_Error
+  (*FT_CID_GetIsInternallyCIDKeyedFunc)( FT_Face   face,
+                                         FT_Bool  *is_cid );
+  typedef FT_Error
+  (*FT_CID_GetCIDFromGlyphIndexFunc)( FT_Face   face,
+                                      FT_UInt   glyph_index,
+                                      FT_UInt  *cid );
 
   FT_DEFINE_SERVICE( CID )
   {
     FT_CID_GetRegistryOrderingSupplementFunc  get_ros;
+    FT_CID_GetIsInternallyCIDKeyedFunc        get_is_cid;
+    FT_CID_GetCIDFromGlyphIndexFunc           get_cid_from_glyph_index;
   };
 
   /* */

src/base/ftcid.c

@@ -4,7 +4,7 @@
 /*                                                                         */
 /*    FreeType API for accessing CID font information.                     */
 /*                                                                         */
-/*  Copyright 2007 by Derek Clegg.                                         */
+/*  Copyright 2007, 2009 by Derek Clegg, Michael Toftdal.                  */
 /*                                                                         */
 /*  This file is part of the FreeType project, and may only be used,       */
 /*  modified, and distributed under the terms of the FreeType project      */
@@ -16,6 +16,7 @@
 
 
 #include <ft2build.h>
+#include FT_CID_H
 #include FT_INTERNAL_OBJECTS_H
 #include FT_SERVICE_CID_H
 
@@ -60,4 +61,57 @@
   }
 
 
+  FT_EXPORT_DEF( FT_Error )
+  FT_Get_CID_Is_Internally_CID_Keyed( FT_Face   face,
+                                      FT_Bool  *is_cid )
+  {
+    FT_Error  error = FT_Err_Invalid_Argument;
+    FT_Bool   ic = 0;
+
+
+    if ( face )
+    {
+      FT_Service_CID  service;
+
+
+      FT_FACE_FIND_SERVICE( face, service, CID );
+
+      if ( service && service->get_is_cid )
+        error = service->get_is_cid( face, &ic);
+    }
+
+    if ( is_cid )
+      *is_cid = ic;
+
+    return error;
+  }
+
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Get_CID_From_Glyph_Index( FT_Face   face,
+                               FT_UInt   glyph_index,
+                               FT_UInt  *cid )
+  {
+    FT_Error  error = FT_Err_Invalid_Argument;
+    FT_UInt   c = 0;
+
+
+    if ( face )
+    {
+      FT_Service_CID  service;
+
+
+      FT_FACE_FIND_SERVICE( face, service, CID );
+
+      if ( service && service->get_cid_from_glyph_index )
+        error = service->get_cid_from_glyph_index( face, glyph_index, &c);
+    }
+
+    if ( cid )
+      *cid = c;
+
+    return error;
+  }
+
+
 /* END */

src/cff/cffdrivr.c

@@ -506,9 +506,74 @@
   }
 
 
+  static FT_Error
+  cff_get_is_cid( CFF_Face  face,
+                  FT_Bool  *is_cid )
+  {
+    FT_Error  error = CFF_Err_Ok;
+    CFF_Font  cff   = (CFF_Font)face->extra.data;
+
+
+    *is_cid = 0;
+
+    if ( cff )
+    {
+      CFF_FontRecDict  dict = &cff->top_font.font_dict;
+
+
+      if ( dict->cid_registry != 0xFFFFU )
+        *is_cid = 1;
+    }
+
+    return error;
+  }
+
+
+  static FT_Error
+  cff_get_cid_from_glyph_index( CFF_Face  face,
+                                FT_UInt   glyph_index,
+                                FT_UInt  *cid )
+  {
+    FT_Error  error = CFF_Err_Ok;
+    CFF_Font  cff;
+
+
+    cff = (CFF_Font)face->extra.data;
+
+    if ( cff )
+    {
+      FT_UInt          c;
+      CFF_FontRecDict  dict = &cff->top_font.font_dict;
+
+
+      if ( dict->cid_registry == 0xFFFFU )
+      {
+        error = CFF_Err_Invalid_Argument;
+        goto Fail;
+      }
+
+      if ( glyph_index > cff->num_glyphs )
+      {
+        error = CFF_Err_Invalid_Argument;
+        goto Fail;
+      }
+
+      c = cff->charset.sids[glyph_index];
+
+      if ( cid )
+        *cid = c;
+    }
+
+  Fail:
+    return error;
+  }
+
+
   static const FT_Service_CIDRec  cff_service_cid_info =
   {
-    (FT_CID_GetRegistryOrderingSupplementFunc)cff_get_ros
+    (FT_CID_GetRegistryOrderingSupplementFunc)cff_get_ros,
+    (FT_CID_GetIsInternallyCIDKeyedFunc)      cff_get_is_cid,
+    (FT_CID_GetCIDFromGlyphIndexFunc)         cff_get_cid_from_glyph_index
   };
 
 

src/cff/cffload.c

@@ -4,7 +4,7 @@
 /*                                                                         */
 /*    OpenType and CFF data/program tables loader (body).                  */
 /*                                                                         */
-/*  Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008 by       */
+/*  Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 by */
 /*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
 /*                                                                         */
 /*  This file is part of the FreeType project, and may only be used,       */
@@ -1540,9 +1540,6 @@
         if ( error )
           goto Exit;
       }
-      else
-        /* CID-keyed fonts only need CIDs */
-        FT_FREE( font->charset.sids );
     }
 
     /* get the font name (/CIDFontName for CID-keyed fonts, */

src/cid/cidriver.c

@@ -122,9 +122,42 @@
   }
 
 
+  static FT_Error
+  cid_get_is_cid( CID_Face  face,
+                  FT_Bool  *is_cid )
+  {
+    FT_Error  error = CID_Err_Ok;
+    FT_UNUSED( face );
+
+
+    if ( is_cid )
+      *is_cid = 1; /* cid driver is only used for CID keyed fonts */
+
+    return error;
+  }
+
+
+  static FT_Error
+  cid_get_cid_from_glyph_index( CID_Face  face,
+                                FT_UInt   glyph_index,
+                                FT_UInt  *cid )
+  {
+    FT_Error  error = CID_Err_Ok;
+    FT_UNUSED( face );
+
+
+    if ( cid )
+      *cid = glyph_index; /* identity mapping */
+
+    return error;
+  }
+
+
   static const FT_Service_CIDRec  cid_service_cid_info =
   {
-    (FT_CID_GetRegistryOrderingSupplementFunc)cid_get_ros
+     (FT_CID_GetRegistryOrderingSupplementFunc)cid_get_ros,
+     (FT_CID_GetIsInternallyCIDKeyedFunc)      cid_get_is_cid,
+     (FT_CID_GetCIDFromGlyphIndexFunc)         cid_get_cid_from_glyph_index
   };