diff options
Diffstat (limited to 'src/3rdparty/freetype/include/freetype/internal/ftcalc.h')
| -rw-r--r-- | src/3rdparty/freetype/include/freetype/internal/ftcalc.h | 246 |
1 files changed, 156 insertions, 90 deletions
diff --git a/src/3rdparty/freetype/include/freetype/internal/ftcalc.h b/src/3rdparty/freetype/include/freetype/internal/ftcalc.h index 818a812359..1811fcd1ea 100644 --- a/src/3rdparty/freetype/include/freetype/internal/ftcalc.h +++ b/src/3rdparty/freetype/include/freetype/internal/ftcalc.h @@ -1,19 +1,19 @@ -/***************************************************************************/ -/* */ -/* ftcalc.h */ -/* */ -/* Arithmetic computations (specification). */ -/* */ -/* Copyright 1996-2018 by */ -/* David Turner, Robert Wilhelm, and Werner Lemberg. */ -/* */ -/* This file is part of the FreeType project, and may only be used, */ -/* modified, and distributed under the terms of the FreeType project */ -/* license, LICENSE.TXT. By continuing to use, modify, or distribute */ -/* this file you indicate that you have read the license and */ -/* understand and accept it fully. */ -/* */ -/***************************************************************************/ +/**************************************************************************** + * + * ftcalc.h + * + * Arithmetic computations (specification). + * + * Copyright (C) 1996-2019 by + * David Turner, Robert Wilhelm, and Werner Lemberg. + * + * This file is part of the FreeType project, and may only be used, + * modified, and distributed under the terms of the FreeType project + * license, LICENSE.TXT. By continuing to use, modify, or distribute + * this file you indicate that you have read the license and + * understand and accept it fully. + * + */ #ifndef FTCALC_H_ @@ -27,11 +27,11 @@ FT_BEGIN_HEADER - /*************************************************************************/ - /* */ - /* FT_MulDiv() and FT_MulFix() are declared in freetype.h. */ - /* */ - /*************************************************************************/ + /************************************************************************** + * + * FT_MulDiv() and FT_MulFix() are declared in freetype.h. + * + */ #ifndef FT_CONFIG_OPTION_NO_ASSEMBLER /* Provide assembler fragments for performance-critical functions. */ @@ -246,29 +246,32 @@ FT_BEGIN_HEADER #endif - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_MulDiv_No_Round */ - /* */ - /* <Description> */ - /* A very simple function used to perform the computation `(a*b)/c' */ - /* (without rounding) with maximum accuracy (it uses a 64-bit */ - /* intermediate integer whenever necessary). */ - /* */ - /* This function isn't necessarily as fast as some processor specific */ - /* operations, but is at least completely portable. */ - /* */ - /* <Input> */ - /* a :: The first multiplier. */ - /* b :: The second multiplier. */ - /* c :: The divisor. */ - /* */ - /* <Return> */ - /* The result of `(a*b)/c'. This function never traps when trying to */ - /* divide by zero; it simply returns `MaxInt' or `MinInt' depending */ - /* on the signs of `a' and `b'. */ - /* */ + /************************************************************************** + * + * @function: + * FT_MulDiv_No_Round + * + * @description: + * A very simple function used to perform the computation '(a*b)/c' + * (without rounding) with maximum accuracy (it uses a 64-bit + * intermediate integer whenever necessary). + * + * This function isn't necessarily as fast as some processor-specific + * operations, but is at least completely portable. + * + * @input: + * a :: + * The first multiplier. + * b :: + * The second multiplier. + * c :: + * The divisor. + * + * @return: + * The result of '(a*b)/c'. This function never traps when trying to + * divide by zero; it simply returns 'MaxInt' or 'MinInt' depending on + * the signs of 'a' and 'b'. + */ FT_BASE( FT_Long ) FT_MulDiv_No_Round( FT_Long a, FT_Long b, @@ -276,12 +279,11 @@ FT_BEGIN_HEADER /* - * 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 values are as precise as possible to get a correct result during - * the 64bit multiplication. Let `sa' and `sb' be the scaling factors of - * `a' and `b', respectively, then the scaling factor of the result is - * `sa*sb'. + * 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 + * values are as precise as possible to get a correct result during the + * 64bit multiplication. Let `sa' and `sb' be the scaling factors of `a' + * and `b', respectively, then the scaling factor of the result is `sa*sb'. */ FT_BASE( void ) FT_Matrix_Multiply_Scaled( const FT_Matrix* a, @@ -290,8 +292,23 @@ FT_BEGIN_HEADER /* - * A variant of FT_Vector_Transform. See comments for - * FT_Matrix_Multiply_Scaled. + * Check a matrix. If the transformation would lead to extreme shear or + * extreme scaling, for example, return 0. If everything is OK, return 1. + * + * 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 + * + * Value 50 is heuristic. + */ + FT_BASE( FT_Bool ) + FT_Matrix_Check( const FT_Matrix* matrix ); + + + /* + * A variant of FT_Vector_Transform. See comments for + * FT_Matrix_Multiply_Scaled. */ FT_BASE( void ) FT_Vector_Transform_Scaled( FT_Vector* vector, @@ -300,22 +317,22 @@ FT_BEGIN_HEADER /* - * This function normalizes a vector and returns its original length. - * The normalized vector is a 16.16 fixed-point unit vector with length - * close to 0x10000. The accuracy of the returned length is limited to - * 16 bits also. The function utilizes quick inverse square root - * approximation without divisions and square roots relying on Newton's - * iterations instead. + * This function normalizes a vector and returns its original length. The + * normalized vector is a 16.16 fixed-point unit vector with length close + * to 0x10000. The accuracy of the returned length is limited to 16 bits + * also. The function utilizes quick inverse square root approximation + * without divisions and square roots relying on Newton's iterations + * instead. */ FT_BASE( FT_UInt32 ) FT_Vector_NormLen( FT_Vector* vector ); /* - * Return -1, 0, or +1, depending on the orientation of a given corner. - * We use the Cartesian coordinate system, with positive vertical values - * going upwards. The function returns +1 if the corner turns to the - * left, -1 to the right, and 0 for undecidable cases. + * Return -1, 0, or +1, depending on the orientation of a given corner. We + * use the Cartesian coordinate system, with positive vertical values going + * upwards. The function returns +1 if the corner turns to the left, -1 to + * the right, and 0 for undecidable cases. */ FT_BASE( FT_Int ) ft_corner_orientation( FT_Pos in_x, @@ -325,9 +342,9 @@ FT_BEGIN_HEADER /* - * Return TRUE if a corner is flat or nearly flat. This is equivalent to - * saying that the corner point is close to its neighbors, or inside an - * ellipse defined by the neighbor focal points to be more precise. + * Return TRUE if a corner is flat or nearly flat. This is equivalent to + * saying that the corner point is close to its neighbors, or inside an + * ellipse defined by the neighbor focal points to be more precise. */ FT_BASE( FT_Int ) ft_corner_is_flat( FT_Pos in_x, @@ -337,10 +354,11 @@ FT_BEGIN_HEADER /* - * Return the most significant bit index. + * Return the most significant bit index. */ #ifndef FT_CONFIG_OPTION_NO_ASSEMBLER + #if defined( __GNUC__ ) && \ ( __GNUC__ > 3 || ( __GNUC__ == 3 && __GNUC_MINOR__ >= 4 ) ) @@ -352,9 +370,34 @@ FT_BEGIN_HEADER #define FT_MSB( x ) ( 31 - __builtin_clzl( x ) ) +#endif /* __GNUC__ */ + + +#elif defined( _MSC_VER ) && ( _MSC_VER >= 1400 ) + +#if FT_SIZEOF_INT == 4 + +#include <intrin.h> +#pragma intrinsic( _BitScanReverse ) + + static __inline FT_Int32 + FT_MSB_i386( FT_UInt32 x ) + { + unsigned long where; + + + _BitScanReverse( &where, x ); + + return (FT_Int32)where; + } + +#define FT_MSB( x ) ( FT_MSB_i386( x ) ) + #endif -#endif /* __GNUC__ */ +#endif /* _MSC_VER */ + + #endif /* !FT_CONFIG_OPTION_NO_ASSEMBLER */ #ifndef FT_MSB @@ -366,8 +409,8 @@ FT_BEGIN_HEADER /* - * Return sqrt(x*x+y*y), which is the same as `FT_Vector_Length' but uses - * two fixed-point arguments instead. + * Return sqrt(x*x+y*y), which is the same as `FT_Vector_Length' but uses + * two fixed-point arguments instead. */ FT_BASE( FT_Fixed ) FT_Hypot( FT_Fixed x, @@ -376,23 +419,24 @@ FT_BEGIN_HEADER #if 0 - /*************************************************************************/ - /* */ - /* <Function> */ - /* FT_SqrtFixed */ - /* */ - /* <Description> */ - /* Computes the square root of a 16.16 fixed-point value. */ - /* */ - /* <Input> */ - /* x :: The value to compute the root for. */ - /* */ - /* <Return> */ - /* The result of `sqrt(x)'. */ - /* */ - /* <Note> */ - /* This function is not very fast. */ - /* */ + /************************************************************************** + * + * @function: + * FT_SqrtFixed + * + * @description: + * Computes the square root of a 16.16 fixed-point value. + * + * @input: + * x :: + * The value to compute the root for. + * + * @return: + * The result of 'sqrt(x)'. + * + * @note: + * This function is not very fast. + */ FT_BASE( FT_Int32 ) FT_SqrtFixed( FT_Int32 x ); @@ -409,14 +453,23 @@ FT_BEGIN_HEADER : ( -( ( 32 - (x) ) & -64 ) ) ) /* - * The following macros have two purposes. + * The following macros have two purposes. * - * . Tag places where overflow is expected and harmless. + * - Tag places where overflow is expected and harmless. * - * . Avoid run-time sanitizer errors. + * - Avoid run-time sanitizer errors. * - * Use with care! + * Use with care! */ +#define ADD_INT( a, b ) \ + (FT_Int)( (FT_UInt)(a) + (FT_UInt)(b) ) +#define SUB_INT( a, b ) \ + (FT_Int)( (FT_UInt)(a) - (FT_UInt)(b) ) +#define MUL_INT( a, b ) \ + (FT_Int)( (FT_UInt)(a) * (FT_UInt)(b) ) +#define NEG_INT( a ) \ + (FT_Int)( (FT_UInt)0 - (FT_UInt)(a) ) + #define ADD_LONG( a, b ) \ (FT_Long)( (FT_ULong)(a) + (FT_ULong)(b) ) #define SUB_LONG( a, b ) \ @@ -435,6 +488,19 @@ FT_BEGIN_HEADER #define NEG_INT32( a ) \ (FT_Int32)( (FT_UInt32)0 - (FT_UInt32)(a) ) +#ifdef FT_LONG64 + +#define ADD_INT64( a, b ) \ + (FT_Int64)( (FT_UInt64)(a) + (FT_UInt64)(b) ) +#define SUB_INT64( a, b ) \ + (FT_Int64)( (FT_UInt64)(a) - (FT_UInt64)(b) ) +#define MUL_INT64( a, b ) \ + (FT_Int64)( (FT_UInt64)(a) * (FT_UInt64)(b) ) +#define NEG_INT64( a ) \ + (FT_Int64)( (FT_UInt64)0 - (FT_UInt64)(a) ) + +#endif /* FT_LONG64 */ + FT_END_HEADER |