diff options
Diffstat (limited to 'src/3rdparty/freetype/include/freetype/internal/ftcalc.h')
| -rw-r--r-- | src/3rdparty/freetype/include/freetype/internal/ftcalc.h | 50 |
1 files changed, 42 insertions, 8 deletions
diff --git a/src/3rdparty/freetype/include/freetype/internal/ftcalc.h b/src/3rdparty/freetype/include/freetype/internal/ftcalc.h index e6a87db94e..d9aea23602 100644 --- a/src/3rdparty/freetype/include/freetype/internal/ftcalc.h +++ b/src/3rdparty/freetype/include/freetype/internal/ftcalc.h @@ -4,7 +4,7 @@ * * Arithmetic computations (specification). * - * Copyright (C) 1996-2022 by + * Copyright (C) 1996-2023 by * David Turner, Robert Wilhelm, and Werner Lemberg. * * This file is part of the FreeType project, and may only be used, @@ -278,6 +278,40 @@ FT_BEGIN_HEADER FT_Long c ); + /************************************************************************** + * + * @function: + * FT_MulAddFix + * + * @description: + * Compute `(s[0] * f[0] + s[1] * f[1] + ...) / 0x10000`, where `s[n]` is + * usually a 16.16 scalar. + * + * @input: + * s :: + * The array of scalars. + * f :: + * The array of factors. + * count :: + * The number of entries in the array. + * + * @return: + * The result of `(s[0] * f[0] + s[1] * f[1] + ...) / 0x10000`. + * + * @note: + * This function is currently used for the scaled delta computation of + * variation stores. It internally uses 64-bit data types when + * available, otherwise it emulates 64-bit math by using 32-bit + * operations, which produce a correct result but most likely at a slower + * performance in comparison to the implementation base on `int64_t`. + * + */ + FT_BASE( FT_Int32 ) + FT_MulAddFix( FT_Fixed* s, + FT_Int32* f, + FT_UInt count ); + + /* * A variant of FT_Matrix_Multiply which scales its result afterwards. The * idea is that both `a' and `b' are scaled by factors of 10 so that the @@ -298,9 +332,9 @@ FT_BEGIN_HEADER * Based on geometric considerations we use the following inequality to * identify a degenerate matrix. * - * 50 * abs(xx*yy - xy*yx) < xx^2 + xy^2 + yx^2 + yy^2 + * 32 * abs(xx*yy - xy*yx) < xx^2 + xy^2 + yx^2 + yy^2 * - * Value 50 is heuristic. + * Value 32 is heuristic. */ FT_BASE( FT_Bool ) FT_Matrix_Check( const FT_Matrix* matrix ); @@ -413,11 +447,11 @@ FT_BEGIN_HEADER extern __inline FT_Int32 FT_MSB_i386( FT_UInt32 x ); -#pragma aux FT_MSB_i386 = \ - "bsr eax, eax" \ - parm [eax] nomemory \ - value [eax] \ - modify exact [eax] nomemory; +#pragma aux FT_MSB_i386 = \ + "bsr eax, eax" \ + __parm [__eax] __nomemory \ + __value [__eax] \ + __modify __exact [__eax] __nomemory; #define FT_MSB( x ) FT_MSB_i386( x ) |