[Git][freetype/freetype][apodtele-master-patch-33657] [type1/MM] Round d

Alexei Podtelezhnikov pushed to branch apodtele-master-patch-33657 at FreeType / FreeType

Commits:

dacbb554

by Alexei Podtelezhnikov at 2023-02-10T08:24:33-05:00

[type1/MM] Round design coordinates.

The design coordinates for MM fonts were not rounded. For example,
`FT_Get_Var_Design_Coordinates` returned values with fractional part.

* src/type1/t1load.c (mm_axis_unmap): Refactor with rounding.

* include/freetype/ftmm.h (FT_Var_Axis, FT_Set_Var_Design_Coordinates,
FT_Get_Var_Design_Coordinates): Reword documentation.

2 changed files:

include/freetype/ftmm.h
src/type1/t1load.c

Changes:

include/freetype/ftmm.h

@@ -153,7 +153,7 @@ FT_BEGIN_HEADER
     * @note:
     *   The fields `minimum`, `def`, and `maximum` are 16.16 fractional values
     *   for TrueType GX and OpenType variation fonts.  For Adobe MM fonts, the
 -   *   values are integers.
 +   *   values are whole numbers (i.e., the fractional part is zero).
     */
    typedef struct  FT_Var_Axis_
+   {
@@ -399,8 +399,8 @@ FT_BEGIN_HEADER
+    *
     * @note:
     *   The design coordinates are 16.16 fractional values for TrueType GX and
 -   *   OpenType variation fonts.  For Adobe MM fonts, the values are
 -   *   integers.
 +   *   OpenType variation fonts.  For Adobe MM fonts, the values are supposed
 +   *   to be whole numbers (i.e., the fractional part is zero).
+    *
     *   [Since 2.8.1] To reset all axes to the default values, call the
     *   function with `num_coords` set to zero and `coords` set to `NULL`.
@@ -446,8 +446,8 @@ FT_BEGIN_HEADER
+    *
     * @note:
     *   The design coordinates are 16.16 fractional values for TrueType GX and
 -   *   OpenType variation fonts.  For Adobe MM fonts, the values are
 -   *   integers.
 +   *   OpenType variation fonts.  For Adobe MM fonts, the values are whole
 +   *   numbers (i.e., the fractional part is zero).
+    *
     * @since:
     *   2.7.1

src/type1/t1load.c

@@ -225,11 +225,12 @@
      for ( j = 1; j < axismap->num_points; j++ )
+     {
        if ( ncv <= axismap->blend_points[j] )
 -        return INT_TO_FIXED( axismap->design_points[j - 1] ) +
 -               ( axismap->design_points[j] - axismap->design_points[j - 1] ) *
 -               FT_DivFix( ncv - axismap->blend_points[j - 1],
 -                          axismap->blend_points[j] -
 -                            axismap->blend_points[j - 1] );
 +        return INT_TO_FIXED( axismap->design_points[j - 1] +
 +                               FT_MulDiv( ncv - axismap->blend_points[j - 1],
 +                                          axismap->design_points[j] -
 +                                            axismap->design_points[j - 1],
 +                                          axismap->blend_points[j] -
 +                                            axismap->blend_points[j - 1] ) );
+     }
      return INT_TO_FIXED( axismap->design_points[axismap->num_points - 1] );

From:	Alexei Podtelezhnikov (@apodtele)
Subject:	[Git][freetype/freetype][apodtele-master-patch-33657] [type1/MM] Round design coordinates.
Date:	Fri, 10 Feb 2023 13:27:28 +0000