[cff] Implement CFF2 support (2/2).

The font variation code.  All parts dependent on the GX code in the
`truetype' module are guarded with TT_CONFIG_OPTION_GX_VAR_SUPPORT.
In other words, you can still compile the `cff' module without
defining TT_CONFIG_OPTION_GX_VAR_SUPPORT (which brings you CFF2
support without font variation).

* src/cff/cf2font.c (cf2_font_setup): Add support for font
variation.
* src/cff/cf2font.h (CF2_Font): Add fields for variation data.

* src/cff/cf2ft.c (cf2_free_instance): Free blend data.
(cf2_getVStore, cf2_getNormalizedVector): New functions.
* src/cff/cf2ft.h: Updated.

* src/cff/cf2intrp.c: Include `cffload.h'.
(cf2_cmdRESERVED_15, cf2_cmdRESERVED_16): Replace with...
(cf2_cmdVSINDEX, cf2_cmdBLEND): ... this new enum values.
(cf2_doBlend): New function.
(cf2_interpT2CharString): Handle `vsindex' and `blend' opcodes.

* src/cff/cffload.c (FT_fdot14ToFixed): New macro.
(cff_vstore_done, cff_vstore_load): New functions.
(cff_blend_clear, cff_blend_doBlend, cff_blend_build_vector,
cff_blend_check_vector): New functions.
(cff_load_private_dict): Add arguments for blend vector.
Handle blend data.
(cff_subfont_load, cff_subfont_done): Updated.
(cff_font_load): Handle CFF2 variation store data.
(cff_font_done): Updated.
* src/cff/cffload.h: Include `cffparse.h'.
Updated.

* src/cff/cffobjs.c (cff_face_done): Updated.

* src/cff/cffparse.c: Include `cffload.h'.
(cff_parse_num): Handle internal value 255.
(cff_parse_vsindex, cff_parse_blend): New functions.
(CFF_FIELD_BLEND): New macro.
(cff_parser_run): Updated.
* src/cff/cffparse.h (cff_kind_blend): New enum value.

* src/cff/cfftoken.h: Handle `vstore', `vsindex', and `blend'
dictionary values.

* src/cff/cfftypes.h (CFF_VarData, CFF_AxisCoords, CFF_VarRegion,
CFF_VStore, CFF_Blend): New structures.
(CFF_FontRecDict): Add `vstore_offset' field.
(CFF_Private): Add `vsindex' field.
(CFF_SubFont): Add fields for blend data.
(CFF_Font): Add `vstore' field.

* src/truetype/ttgxvar.c (TT_Get_MM_Var): `CFF2' is equal to `gvar',
since glyph variation data is directly embedded.
(TT_Set_MM_Blend): Don't load `gvar' table for CFF2 fonts.

1 files changed, 5 insertions, 0 deletions

diff --git a/src/cff/cffobjs.c b/src/cff/cffobjs.c
index 7302e0326..394633b16 100644
--- a/src/cff/cffobjs.c
+++ b/src/cff/cffobjs.c
@@ -1095,6 +1095,11 @@
         FT_FREE( face->extra.data );
       }
     }
+
+#ifdef TT_CONFIG_OPTION_GX_VAR_SUPPORT
+    cff_done_blend( face );
+    face->blend = NULL;
+#endif
   }