diff options
Diffstat (limited to 'src/3rdparty/freetype/src/base/fttrigon.c')
| -rw-r--r-- | src/3rdparty/freetype/src/base/fttrigon.c | 76 |
1 files changed, 34 insertions, 42 deletions
diff --git a/src/3rdparty/freetype/src/base/fttrigon.c b/src/3rdparty/freetype/src/base/fttrigon.c index d6dd098c42..38721977c7 100644 --- a/src/3rdparty/freetype/src/base/fttrigon.c +++ b/src/3rdparty/freetype/src/base/fttrigon.c @@ -1,33 +1,33 @@ -/***************************************************************************/ -/* */ -/* fttrigon.c */ -/* */ -/* FreeType trigonometric functions (body). */ -/* */ -/* Copyright 2001-2018 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. */ -/* */ -/***************************************************************************/ - - /*************************************************************************/ - /* */ - /* This is a fixed-point CORDIC implementation of trigonometric */ - /* functions as well as transformations between Cartesian and polar */ - /* coordinates. The angles are represented as 16.16 fixed-point values */ - /* in degrees, i.e., the angular resolution is 2^-16 degrees. Note that */ - /* only vectors longer than 2^16*180/pi (or at least 22 bits) on a */ - /* discrete Cartesian grid can have the same or better angular */ - /* resolution. Therefore, to maintain this precision, some functions */ - /* require an interim upscaling of the vectors, whereas others operate */ - /* with 24-bit long vectors directly. */ - /* */ - /*************************************************************************/ +/**************************************************************************** + * + * fttrigon.c + * + * FreeType trigonometric functions (body). + * + * Copyright (C) 2001-2019 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. + * + */ + + /************************************************************************** + * + * This is a fixed-point CORDIC implementation of trigonometric + * functions as well as transformations between Cartesian and polar + * coordinates. The angles are represented as 16.16 fixed-point values + * in degrees, i.e., the angular resolution is 2^-16 degrees. Note that + * only vectors longer than 2^16*180/pi (or at least 22 bits) on a + * discrete Cartesian grid can have the same or better angular + * resolution. Therefore, to maintain this precision, some functions + * require an interim upscaling of the vectors, whereas others operate + * with 24-bit long vectors directly. + * + */ #include <ft2build.h> #include FT_INTERNAL_OBJECTS_H @@ -325,10 +325,10 @@ FT_EXPORT_DEF( FT_Fixed ) FT_Tan( FT_Angle angle ) { - FT_Vector v; + FT_Vector v = { 1 << 24, 0 }; - FT_Vector_Unit( &v, angle ); + ft_trig_pseudo_rotate( &v, angle ); return FT_DivFix( v.y, v.x ); } @@ -372,14 +372,6 @@ } - /* these macros return 0 for positive numbers, - and -1 for negative ones */ -#define FT_SIGN_LONG( x ) ( (x) >> ( FT_SIZEOF_LONG * 8 - 1 ) ) -#define FT_SIGN_INT( x ) ( (x) >> ( FT_SIZEOF_INT * 8 - 1 ) ) -#define FT_SIGN_INT32( x ) ( (x) >> 31 ) -#define FT_SIGN_INT16( x ) ( (x) >> 15 ) - - /* documentation is in fttrigon.h */ FT_EXPORT_DEF( void ) @@ -408,8 +400,8 @@ FT_Int32 half = (FT_Int32)1L << ( shift - 1 ); - vec->x = ( v.x + half + FT_SIGN_LONG( v.x ) ) >> shift; - vec->y = ( v.y + half + FT_SIGN_LONG( v.y ) ) >> shift; + vec->x = ( v.x + half - ( v.x < 0 ) ) >> shift; + vec->y = ( v.y + half - ( v.y < 0 ) ) >> shift; } else { |