Add a setweightvector analogue in Freetype

Avoids the need to recreate the FT font everytime the weightvector changes.

These Freetype changes have been accepted upstream:
http://git.savannah.gnu.org/cgit/freetype/freetype2.git/commit/?id=78a1e69517ca067224d6e33beffd25e2ec8361d2

8 files changed, 339 insertions, 74 deletions

diff --git a/freetype/include/freetype/ftmm.h b/freetype/include/freetype/ftmm.h
index 9948102c1..8be85ef07 100644
--- a/freetype/include/freetype/ftmm.h
+++ b/freetype/include/freetype/ftmm.h
@@ -527,6 +527,87 @@ FT_BEGIN_HEADER
   /*************************************************************************/
   /*                                                                       */
   /* <Function>                                                            */
+  /*    FT_Set_MM_WeightVector                                             */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    For Adobe MM fonts, choose an interpolated font design by          */
+  /*    directly setting the weight vector.                                */
+  /*                                                                       */
+  /*    This function can't be used with TrueType GX or OpenType variation */
+  /*    fonts.                                                             */
+  /*                                                                       */
+  /* <InOut>                                                               */
+  /*    face         :: A handle to the source face.                       */
+  /*                                                                       */
+  /* <Input>                                                               */
+  /*    len          :: The length of the weight vector array. If it is    */
+  /*                    larger than the number of designs, the extra       */
+  /*                    values are ignored. If it is less than the number  */
+  /*                    of designs, the remaining values are set to zero.  */
+  /*                                                                       */
+  /*    weightvector :: An array representing the weight vector.           */
+  /*                                                                       */
+  /* <Return>                                                              */
+  /*    FreeType error code.  0~means success.                             */
+  /*                                                                       */
+  /* <Note>                                                                */
+  /*       Adobe Multiple Master fonts limit the number of designs, and    */
+  /*       thus the length of the WeightVector to 16.                      */
+  /*                                                                       */
+  /*       If len is zero and weightvector is NULL, the WeightVector is    */
+  /*       reset to the default values.                                    */
+  /*       The Adobe documentation also states that the values in the      */
+  /*       WeightVector must total 1.0 +/- 0.001. In practice this does    */
+  /*       not seem to be enforced, so is not enforced, here either.       */
+  /*                                                                       */
+  FT_EXPORT( FT_Error )
+  FT_Set_MM_WeightVector( FT_Face    face,
+                          FT_UInt    len,
+                          FT_Fixed*  weightvector );
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
+  /*    FT_Get_MM_WeightVector                                             */
+  /*                                                                       */
+  /* <Description>                                                         */
+  /*    For Adobe MM fonts, retrieve the current weight vector of the font */
+  /*                                                                       */
+  /*    This function can't be used with TrueType GX or OpenType variation */
+  /*    fonts.                                                             */
+  /*                                                                       */
+  /* <InOut>                                                               */
+  /*    face         :: A handle to the source face.                       */
+  /*                                                                       */
+  /* <InOut>                                                               */
+  /*    len          :: Pointer to the size of the array to be filled. If  */
+  /*                    size of the array less than the number of designs, */
+  /*                    an Invalid_Argument is returned, and len is set to */
+  /*                    the required size (the number of designs). If the  */
+  /*                    size of the array is greater than the number of    */
+  /*                    designs, the remaining entries are set to 0. On    */
+  /*                    successful completion, len is set to the number of */
+  /*                    designs (i.e. the number of values written to the  */
+  /*                    array.                                             */
+  /*                                                                       */
+  /* <Output>                                                              */
+  /*    weightvector :: An array to be filled.                             */
+  /*                                                                       */
+  /* <Return>                                                              */
+  /*    FreeType error code.  0~means success.                             */
+  /*                                                                       */
+  /* <Note>                                                                */
+  /*       Adobe Multiple Master fonts limit the number of designs, and    */
+  /*       thus the length of the WeightVector to 16.                      */
+  /*                                                                       */
+  FT_EXPORT( FT_Error )
+  FT_Get_MM_WeightVector( FT_Face   face,
+                          FT_UInt*  len,
+                          FT_Fixed* weightvector );
+
+  /*************************************************************************/
+  /*                                                                       */
+  /* <Function>                                                            */
   /*    FT_Get_Var_Blend_Coordinates                                       */
   /*                                                                       */
   /* <Description>                                                         */
diff --git a/freetype/include/freetype/internal/services/svmm.h b/freetype/include/freetype/internal/services/svmm.h
index bcbb38e2c..882862e01 100644
--- a/freetype/include/freetype/internal/services/svmm.h
+++ b/freetype/include/freetype/internal/services/svmm.h
@@ -86,17 +86,31 @@ FT_BEGIN_HEADER
   typedef void
   (*FT_Done_Blend_Func)( FT_Face );
 
+  /* use return value -1 to indicate that the new coordinates  */
+  /* are equal to the current ones; no changes are thus needed */
+  typedef FT_Error
+  (*FT_Set_MM_WeightVector_Func)( FT_Face    face,
+                                  FT_UInt    len,
+                                  FT_Fixed*  weight_vector );
+
+  typedef FT_Error
+  (*FT_Get_MM_WeightVector_Func)( FT_Face   face,
+                                  FT_UInt*  len,
+                                  FT_Fixed* weight_vector );
+
 
   FT_DEFINE_SERVICE( MultiMasters )
   {
-    FT_Get_MM_Func          get_mm;
-    FT_Set_MM_Design_Func   set_mm_design;
-    FT_Set_MM_Blend_Func    set_mm_blend;
-    FT_Get_MM_Blend_Func    get_mm_blend;
-    FT_Get_MM_Var_Func      get_mm_var;
-    FT_Set_Var_Design_Func  set_var_design;
-    FT_Get_Var_Design_Func  get_var_design;
-    FT_Set_Instance_Func    set_instance;
+    FT_Get_MM_Func                 get_mm;
+    FT_Set_MM_Design_Func          set_mm_design;
+    FT_Set_MM_Blend_Func           set_mm_blend;
+    FT_Get_MM_Blend_Func           get_mm_blend;
+    FT_Get_MM_Var_Func             get_mm_var;
+    FT_Set_Var_Design_Func         set_var_design;
+    FT_Get_Var_Design_Func         get_var_design;
+    FT_Set_Instance_Func           set_instance;
+    FT_Set_MM_WeightVector_Func    set_mm_weightvector;
+    FT_Get_MM_WeightVector_Func    get_mm_weightvector;
 
     /* for internal use; only needed for code sharing between modules */
     FT_Get_Var_Blend_Func   get_var_blend;
@@ -106,29 +120,33 @@ FT_BEGIN_HEADER
 
 #ifndef FT_CONFIG_OPTION_PIC
 
-#define FT_DEFINE_SERVICE_MULTIMASTERSREC( class_,          \
-                                           get_mm_,         \
-                                           set_mm_design_,  \
-                                           set_mm_blend_,   \
-                                           get_mm_blend_,   \
-                                           get_mm_var_,     \
-                                           set_var_design_, \
-                                           get_var_design_, \
-                                           set_instance_,   \
-                                           get_var_blend_,  \
-                                           done_blend_ )    \
-  static const FT_Service_MultiMastersRec  class_ =         \
-  {                                                         \
-    get_mm_,                                                \
-    set_mm_design_,                                         \
-    set_mm_blend_,                                          \
-    get_mm_blend_,                                          \
-    get_mm_var_,                                            \
-    set_var_design_,                                        \
-    get_var_design_,                                        \
-    set_instance_,                                          \
-    get_var_blend_,                                         \
-    done_blend_                                             \
+#define FT_DEFINE_SERVICE_MULTIMASTERSREC( class_,           \
+                                           get_mm_,          \
+                                           set_mm_design_,   \
+                                           set_mm_blend_,    \
+                                           get_mm_blend_,    \
+                                           get_mm_var_,      \
+                                           set_var_design_,  \
+                                           get_var_design_,  \
+                                           set_instance_,    \
+                                           set_weightvector_,\
+                                           get_weightvector_,\
+                                           get_var_blend_,   \
+                                           done_blend_ )     \
+  static const FT_Service_MultiMastersRec  class_ =          \
+  {                                                          \
+    get_mm_,                                                 \
+    set_mm_design_,                                          \
+    set_mm_blend_,                                           \
+    get_mm_blend_,                                           \
+    get_mm_var_,                                             \
+    set_var_design_,                                         \
+    get_var_design_,                                         \
+    set_instance_,                                           \
+    set_weightvector_,                                       \
+    get_weightvector_,                                       \
+    get_var_blend_,                                          \
+    done_blend_                                              \
   };
 
 #else /* FT_CONFIG_OPTION_PIC */
@@ -142,21 +160,25 @@ FT_BEGIN_HEADER
                                            set_var_design_,      \
                                            get_var_design_,      \
                                            set_instance_,        \
+                                           set_weightvector,     \
+                                           get_weightvector,     \
                                            get_var_blend_,       \
                                            done_blend_ )         \
   void                                                           \
   FT_Init_Class_ ## class_( FT_Service_MultiMastersRec*  clazz ) \
   {                                                              \
-    clazz->get_mm         = get_mm_;                             \
-    clazz->set_mm_design  = set_mm_design_;                      \
-    clazz->set_mm_blend   = set_mm_blend_;                       \
-    clazz->get_mm_blend   = get_mm_blend_;                       \
-    clazz->get_mm_var     = get_mm_var_;                         \
-    clazz->set_var_design = set_var_design_;                     \
-    clazz->get_var_design = get_var_design_;                     \
-    clazz->set_instance   = set_instance_;                       \
-    clazz->get_var_blend  = get_var_blend_;                      \
-    clazz->done_blend     = done_blend_;                         \
+    clazz->get_mm           = get_mm_;                             \
+    clazz->set_mm_design    = set_mm_design_;                      \
+    clazz->set_mm_blend     = set_mm_blend_;                       \
+    clazz->get_mm_blend     = get_mm_blend_;                       \
+    clazz->get_mm_var       = get_mm_var_;                         \
+    clazz->set_var_design   = set_var_design_;                     \
+    clazz->get_var_design   = get_var_design_;                     \
+    clazz->set_instance     = set_instance_;                       \
+    clazz->set_weightvector = set_weightvector;                    \
+    clazz->get_weightvector = get_weightvector;                    \
+    clazz->get_var_blend    = get_var_blend_;                      \
+    clazz->done_blend       = done_blend_;                         \
   }
 
 #endif /* FT_CONFIG_OPTION_PIC */
diff --git a/freetype/src/base/ftmm.c b/freetype/src/base/ftmm.c
index 800441bca..8e841c070 100644
--- a/freetype/src/base/ftmm.c
+++ b/freetype/src/base/ftmm.c
@@ -198,6 +198,65 @@
     return error;
   }
 
+  /* documentation is in ftmm.h */
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Set_MM_WeightVector( FT_Face    face,
+                          FT_UInt    len,
+                          FT_Fixed*  weightvector )
+  {
+    FT_Error                 error;
+    FT_Service_MultiMasters  service;
+
+
+    /* check of `face' delayed to `ft_face_get_mm_service' */
+
+    if ( len && !weightvector )
+      return FT_THROW( Invalid_Argument );
+
+    error = ft_face_get_mm_service( face, &service );
+    if ( !error )
+    {
+      error = FT_ERR( Invalid_Argument );
+      if ( service->set_mm_weightvector )
+        error = service->set_mm_weightvector( face, len, weightvector );
+    }
+
+    /* enforce recomputation of auto-hinting data */
+    if ( !error && face->autohint.finalizer )
+    {
+      face->autohint.finalizer( face->autohint.data );
+      face->autohint.data = NULL;
+    }
+
+    return error;
+  }
+
+  FT_EXPORT_DEF( FT_Error )
+  FT_Get_MM_WeightVector( FT_Face    face,
+                          FT_UInt*    len,
+                          FT_Fixed*  weightvector )
+  {
+    FT_Error                 error;
+    FT_Service_MultiMasters  service;
+
+
+    /* check of `face' delayed to `ft_face_get_mm_service' */
+
+    if ( len && !weightvector )
+      return FT_THROW( Invalid_Argument );
+
+    error = ft_face_get_mm_service( face, &service );
+    if ( !error )
+    {
+      error = FT_ERR( Invalid_Argument );
+      if ( service->get_mm_weightvector )
+        error = service->get_mm_weightvector( face, len, weightvector );
+    }
+
+    return error;
+  }
+
 
   /* documentation is in ftmm.h */
 
diff --git a/freetype/src/cff/cffdrivr.c b/freetype/src/cff/cffdrivr.c
index df896848d..06e2d743d 100644
--- a/freetype/src/cff/cffdrivr.c
+++ b/freetype/src/cff/cffdrivr.c
@@ -859,6 +859,28 @@
     return mm->get_mm_blend( FT_FACE( face ), num_coords, coords );
   }
 
+  static FT_Error
+  cff_set_mm_weightvector( CFF_Face   face,
+                        FT_UInt    len,
+                        FT_Fixed*  weightvector )
+  {
+    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+
+
+    return mm->set_mm_weightvector( FT_FACE( face ), len, weightvector );
+  }
+
+
+  static FT_Error
+  cff_get_mm_weightvector( CFF_Face   face,
+                           FT_UInt*   len,
+                           FT_Fixed*  weightvector )
+  {
+    FT_Service_MultiMasters  mm = (FT_Service_MultiMasters)face->mm;
+
+
+    return mm->get_mm_weightvector( FT_FACE( face ), len, weightvector );
+  }
 
   static FT_Error
   cff_get_mm_var( CFF_Face     face,
@@ -909,17 +931,19 @@
   FT_DEFINE_SERVICE_MULTIMASTERSREC(
     cff_service_multi_masters,
 
-    (FT_Get_MM_Func)        NULL,                   /* get_mm         */
-    (FT_Set_MM_Design_Func) NULL,                   /* set_mm_design  */
-    (FT_Set_MM_Blend_Func)  cff_set_mm_blend,       /* set_mm_blend   */
-    (FT_Get_MM_Blend_Func)  cff_get_mm_blend,       /* get_mm_blend   */
-    (FT_Get_MM_Var_Func)    cff_get_mm_var,         /* get_mm_var     */
-    (FT_Set_Var_Design_Func)cff_set_var_design,     /* set_var_design */
-    (FT_Get_Var_Design_Func)cff_get_var_design,     /* get_var_design */
-    (FT_Set_Instance_Func)  cff_set_instance,       /* set_instance   */
-
-    (FT_Get_Var_Blend_Func) cff_get_var_blend,      /* get_var_blend  */
-    (FT_Done_Blend_Func)    cff_done_blend          /* done_blend     */
+    (FT_Get_MM_Func)               NULL,                   /* get_mm         */
+    (FT_Set_MM_Design_Func)        NULL,                   /* set_mm_design  */
+    (FT_Set_MM_Blend_Func)         cff_set_mm_blend,       /* set_mm_blend   */
+    (FT_Get_MM_Blend_Func)         cff_get_mm_blend,       /* get_mm_blend   */
+    (FT_Get_MM_Var_Func)           cff_get_mm_var,         /* get_mm_var     */
+    (FT_Set_Var_Design_Func)       cff_set_var_design,     /* set_var_design */
+    (FT_Get_Var_Design_Func)       cff_get_var_design,     /* get_var_design */
+    (FT_Set_Instance_Func)         cff_set_instance,       /* set_instance   */
+    (FT_Set_MM_WeightVector_Func)  cff_set_mm_weightvector,/* set_mm_weightvector */
+    (FT_Get_MM_WeightVector_Func)  cff_get_mm_weightvector,/* get_mm_weightvector */
+
+    (FT_Get_Var_Blend_Func)        cff_get_var_blend,      /* get_var_blend  */
+    (FT_Done_Blend_Func)           cff_done_blend          /* done_blend     */
   )
 
 
diff --git a/freetype/src/truetype/ttdriver.c b/freetype/src/truetype/ttdriver.c
index 820cafbb8..88b499ce0 100644
--- a/freetype/src/truetype/ttdriver.c
+++ b/freetype/src/truetype/ttdriver.c
@@ -491,17 +491,19 @@
   FT_DEFINE_SERVICE_MULTIMASTERSREC(
     tt_service_gx_multi_masters,
 
-    (FT_Get_MM_Func)        NULL,                   /* get_mm         */
-    (FT_Set_MM_Design_Func) NULL,                   /* set_mm_design  */
-    (FT_Set_MM_Blend_Func)  TT_Set_MM_Blend,        /* set_mm_blend   */
-    (FT_Get_MM_Blend_Func)  TT_Get_MM_Blend,        /* get_mm_blend   */
-    (FT_Get_MM_Var_Func)    TT_Get_MM_Var,          /* get_mm_var     */
-    (FT_Set_Var_Design_Func)TT_Set_Var_Design,      /* set_var_design */
-    (FT_Get_Var_Design_Func)TT_Get_Var_Design,      /* get_var_design */
-    (FT_Set_Instance_Func)  TT_Set_Named_Instance,  /* set_instance   */
-
-    (FT_Get_Var_Blend_Func) tt_get_var_blend,       /* get_var_blend  */
-    (FT_Done_Blend_Func)    tt_done_blend           /* done_blend     */
+    (FT_Get_MM_Func)               NULL,                 /* get_mm         */
+    (FT_Set_MM_Design_Func)        NULL,                 /* set_mm_design  */
+    (FT_Set_MM_Blend_Func)         TT_Set_MM_Blend,      /* set_mm_blend   */
+    (FT_Get_MM_Blend_Func)         TT_Get_MM_Blend,      /* get_mm_blend   */
+    (FT_Get_MM_Var_Func)           TT_Get_MM_Var,        /* get_mm_var     */
+    (FT_Set_Var_Design_Func)       TT_Set_Var_Design,    /* set_var_design */
+    (FT_Get_Var_Design_Func)       TT_Get_Var_Design,    /* get_var_design */
+    (FT_Set_Instance_Func)         TT_Set_Named_Instance,/* set_instance   */
+    (FT_Set_MM_WeightVector_Func)  NULL,                 /* set_mm_weightvector */
+    (FT_Get_MM_WeightVector_Func)  NULL,                 /* get_mm_weightvector */
+
+    (FT_Get_Var_Blend_Func)        tt_get_var_blend,     /* get_var_blend  */
+    (FT_Done_Blend_Func)           tt_done_blend         /* done_blend     */
   )
 
   FT_DEFINE_SERVICE_METRICSVARIATIONSREC(
diff --git a/freetype/src/type1/t1driver.c b/freetype/src/type1/t1driver.c
index 029b410b4..8fcb2a385 100644
--- a/freetype/src/type1/t1driver.c
+++ b/freetype/src/type1/t1driver.c
@@ -122,17 +122,19 @@
 #ifndef T1_CONFIG_OPTION_NO_MM_SUPPORT
   static const FT_Service_MultiMastersRec  t1_service_multi_masters =
   {
-    (FT_Get_MM_Func)        T1_Get_Multi_Master,   /* get_mm         */
-    (FT_Set_MM_Design_Func) T1_Set_MM_Design,      /* set_mm_design  */
-    (FT_Set_MM_Blend_Func)  T1_Set_MM_Blend,       /* set_mm_blend   */
-    (FT_Get_MM_Blend_Func)  T1_Get_MM_Blend,       /* get_mm_blend   */
-    (FT_Get_MM_Var_Func)    T1_Get_MM_Var,         /* get_mm_var     */
-    (FT_Set_Var_Design_Func)T1_Set_Var_Design,     /* set_var_design */
-    (FT_Get_Var_Design_Func)T1_Get_Var_Design,     /* get_var_design */
-    (FT_Set_Instance_Func)  T1_Reset_MM_Blend,     /* set_instance   */
-
-    (FT_Get_Var_Blend_Func) NULL,                  /* get_var_blend  */
-    (FT_Done_Blend_Func)    T1_Done_Blend          /* done_blend     */
+    (FT_Get_MM_Func)               T1_Get_Multi_Master,    /* get_mm              */
+    (FT_Set_MM_Design_Func)        T1_Set_MM_Design,       /* set_mm_design       */
+    (FT_Set_MM_Blend_Func)         T1_Set_MM_Blend,        /* set_mm_blend        */
+    (FT_Get_MM_Blend_Func)         T1_Get_MM_Blend,        /* get_mm_blend        */
+    (FT_Get_MM_Var_Func)           T1_Get_MM_Var,          /* get_mm_var          */
+    (FT_Set_Var_Design_Func)       T1_Set_Var_Design,      /* set_var_design      */
+    (FT_Get_Var_Design_Func)       T1_Get_Var_Design,      /* get_var_design      */
+    (FT_Set_Instance_Func)         T1_Reset_MM_Blend,      /* set_instance        */
+    (FT_Set_MM_WeightVector_Func)  T1_Set_MM_WeightVector, /* set_mm_weightvector */
+    (FT_Get_MM_WeightVector_Func)  T1_Get_MM_WeightVector, /* get_mm_weightvector */
+
+    (FT_Get_Var_Blend_Func)        NULL,                   /* get_var_blend       */
+    (FT_Done_Blend_Func)           T1_Done_Blend           /* done_blend          */
   };
 #endif
 
diff --git a/freetype/src/type1/t1load.c b/freetype/src/type1/t1load.c
index 9dfa637a6..94e856058 100644
--- a/freetype/src/type1/t1load.c
+++ b/freetype/src/type1/t1load.c
@@ -475,6 +475,71 @@
     return FT_Err_Ok;
   }
 
+  FT_LOCAL_DEF( FT_Error )
+  T1_Set_MM_WeightVector( T1_Face    face,
+                          FT_UInt    len,
+                          FT_Fixed*  weightvector )
+  {
+    PS_Blend  blend = face->blend;
+    FT_UInt   i, n;
+
+    if ( !blend)
+     return FT_THROW( Invalid_Argument );
+
+    if ( len == 0 && weightvector == NULL )
+    {
+        for ( i = 0; i < blend->num_designs; i++ )
+          blend->weight_vector[i] = blend->default_weight_vector[i];
+    }
+    else
+    {
+      if ( weightvector == NULL )
+        return FT_THROW( Invalid_Argument );
+
+      n = len < blend->num_designs ? len : blend->num_designs;
+
+      for ( i = 0; i < n; i++ )
+          blend->weight_vector[i] = weightvector[i];
+
+      for ( ; i < blend->num_designs; i++ )
+          blend->weight_vector[i] = (FT_Fixed)0;
+
+      if ( len )
+        face->root.face_flags |= FT_FACE_FLAG_VARIATION;
+      else
+        face->root.face_flags &= ~FT_FACE_FLAG_VARIATION;
+    }
+    return FT_Err_Ok;
+  }
+
+
+  FT_LOCAL_DEF( FT_Error )
+  T1_Get_MM_WeightVector( T1_Face    face,
+                          FT_UInt*   len,
+                          FT_Fixed*  weightvector )
+  {
+    PS_Blend  blend = face->blend;
+    FT_UInt   i;
+
+
+    if ( !blend )
+      return FT_THROW( Invalid_Argument );
+    if (*len < blend->num_designs)
+    {
+      *len = blend->num_designs;
+      return FT_THROW( Invalid_Argument );
+    }
+
+    for (i = 0; i < blend->num_designs; i++)
+        weightvector[i] = blend->weight_vector[i];
+    for (; i < *len; i++)
+        weightvector[i] = (FT_Fixed)0;
+
+    *len = blend->num_designs;
+
+    return FT_Err_Ok;
+  }
+
 
   FT_LOCAL_DEF( FT_Error )
   T1_Set_MM_Design( T1_Face   face,
diff --git a/freetype/src/type1/t1load.h b/freetype/src/type1/t1load.h
index 03be3f7f9..5763ccc1e 100644
--- a/freetype/src/type1/t1load.h
+++ b/freetype/src/type1/t1load.h
@@ -106,6 +106,16 @@ FT_BEGIN_HEADER
   FT_LOCAL( void )
   T1_Done_Blend( T1_Face  face );
 
+  FT_LOCAL( FT_Error )
+  T1_Set_MM_WeightVector( T1_Face    face,
+                          FT_UInt    len,
+                          FT_Fixed*  weightvector );
+
+  FT_LOCAL( FT_Error )
+  T1_Get_MM_WeightVector( T1_Face    face,
+                          FT_UInt*   len,
+                          FT_Fixed*  weightvector );
+
 #endif /* !T1_CONFIG_OPTION_NO_MM_SUPPORT */