Adding the function `FT_Get_Next_Char', doing the obvious thing

w.r.t. the selected charmap.

* include/freetype/freetype.h: Add prototype.
* include/freetype/internal/ftdriver.h: Add `FTDriver_getNextChar'
typedef.
(FT_Driver_Class): Use it.
* include/freetype/internal/psnames.h: Add `PS_Next_Unicode_Func'
typedef.
(PSNames_Interface): Use it.
* include/freetype/internal/tttypes.h: Add `TT_CharNext_Func'
typedef.
(TT_CMapTable): Use it.

* src/base/ftobjs.c (FT_Get_Next_Char): New function, implementing
high-level API.
* src/cff/cffdrivr.c (cff_get_next_char): New function.
(cff_driver_class): Add it.
* src/cid/cidriver.c (Cid_Get_Next_Char): New function.
(t1cid_driver_class): Add it.
* src/pcf/pcfdriver.c (PCF_Get_Next_Char): New function.
(pcf_driver_class): Add it.
* src/psnames/psmodule.c (PS_Next_Unicode): New function.
(psnames_interface): Add it.
* src/sfnt/ttcmap.c (code_to_next0, code_to_next2, code_to_next4,
code_to_next6, code_to_next_8_12, code_to_next_10): New auxiliary
functions.
(TT_CharMap_Load): Use them.
* src/truetype/ttdriver.c (Get_Next_Char): New function.
(tt_driver_class): Add it.
* src/type1/t1driver.c (Get_Next_Char): New function.
(t1_driver_class): Add it.
* src/winfnt/winfnt.c (FNT_Get_Next_Char): New function.
(winfnt_driver_class): Add it.

* src/pcf/pcfread.c (pcf_load_font): For now, report Unicode for
Unicode and Latin 1 encodings.

4 files changed, 37 insertions, 0 deletions

diff --git a/include/freetype/freetype.h b/include/freetype/freetype.h
index d4761a80..d6275a6e 100644
--- a/include/freetype/freetype.h
+++ b/include/freetype/freetype.h
@@ -122,6 +122,7 @@ FT_BEGIN_HEADER
   /*    FT_Set_Transform                                                   */
   /*    FT_Load_Glyph                                                      */
   /*    FT_Get_Char_Index                                                  */
+  /*    FT_Get_Next_Char                                                   */
   /*    FT_Get_Name_Index                                                  */
   /*    FT_Load_Char                                                       */
   /*                                                                       */
@@ -2394,6 +2395,27 @@ FT_BEGIN_HEADER
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
+  /*    FT_Get_Next_Char                                                   */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    Returns the next charcode that is defined in the charmap.          */
+  /*                                                                       */
+  /* <Input>                                                               */
+  /*    face     :: A handle to the source face object.                    */
+  /*                                                                       */
+  /*    charcode :: The character code.                                    */
+  /*                                                                       */
+  /* <Return>                                                              */
+  /*    The charcode.  0 means `no encoded values above charcode'.         */
+  /*                                                                       */
+  FT_EXPORT( FT_ULong )
+  FT_Get_Next_Char( FT_Face   face,
+                    FT_ULong  charcode );
+
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
   /*    FT_Get_Name_Index                                                  */
   /*                                                                       */
   /* <Description>                                                         */
diff --git a/include/freetype/internal/ftdriver.h b/include/freetype/internal/ftdriver.h
index 6d585734..d8c73d17 100644
--- a/include/freetype/internal/ftdriver.h
+++ b/include/freetype/internal/ftdriver.h
@@ -75,6 +75,10 @@ FT_BEGIN_HEADER
   (*FTDriver_getCharIndex)( FT_CharMap  charmap,
                             FT_Long     charcode );
 
+  typedef FT_Long
+  (*FTDriver_getNextChar)( FT_CharMap   charmap,
+                           FT_Long      charcode );
+
   typedef FT_Error
   (*FTDriver_getKerning)( FT_Face      face,
                           FT_UInt      left_glyph,
@@ -189,6 +193,7 @@ FT_BEGIN_HEADER
 
     FTDriver_getAdvances    get_advances;
 
+    FTDriver_getNextChar    get_next_char;
   } FT_Driver_Class;
 
 
diff --git a/include/freetype/internal/psnames.h b/include/freetype/internal/psnames.h
index 71700c19..a70b7a90 100644
--- a/include/freetype/internal/psnames.h
+++ b/include/freetype/internal/psnames.h
@@ -166,6 +166,10 @@ FT_BEGIN_HEADER
   (*PS_Lookup_Unicode_Func)( PS_Unicodes*  unicodes,
                              FT_UInt       unicode );
 
+  typedef FT_ULong
+  (*PS_Next_Unicode_Func)( PS_Unicodes*  unicodes,
+                           FT_ULong      unicode );
+
 
   /*************************************************************************/
   /*                                                                       */
@@ -221,6 +225,7 @@ FT_BEGIN_HEADER
     const unsigned short*      adobe_std_encoding;
     const unsigned short*      adobe_expert_encoding;
 
+    PS_Next_Unicode_Func       next_unicode;
   } PSNames_Interface;
 
 
diff --git a/include/freetype/internal/tttypes.h b/include/freetype/internal/tttypes.h
index 4fc504fc..4177d1e3 100644
--- a/include/freetype/internal/tttypes.h
+++ b/include/freetype/internal/tttypes.h
@@ -1049,6 +1049,10 @@ FT_BEGIN_HEADER
   (*TT_CharMap_Func)( TT_CMapTable*  charmap,
                       FT_ULong       char_code );
 
+  typedef FT_ULong
+  (*TT_CharNext_Func)( TT_CMapTable* charmap,
+                       FT_ULong      char_code );
+
 
   /* charmap table */
   struct  TT_CMapTable_
@@ -1072,6 +1076,7 @@ FT_BEGIN_HEADER
     } c;
 
     TT_CharMap_Func  get_index;
+    TT_CharNext_Func get_next_char;
   };