diff options
Diffstat (limited to 'freetype/src/base/ftcalc.c')
| -rw-r--r-- | freetype/src/base/ftcalc.c | 34 |
1 files changed, 29 insertions, 5 deletions
diff --git a/freetype/src/base/ftcalc.c b/freetype/src/base/ftcalc.c index 27448b30a..a1e76e192 100644 --- a/freetype/src/base/ftcalc.c +++ b/freetype/src/base/ftcalc.c @@ -4,7 +4,7 @@ /* */ /* Arithmetic computations (body). */ /* */ -/* Copyright 1996-2006, 2008, 2012-2013 by */ +/* Copyright 1996-2006, 2008, 2012-2014 by */ /* David Turner, Robert Wilhelm, and Werner Lemberg. */ /* */ /* This file is part of the FreeType project, and may only be used, */ @@ -128,7 +128,7 @@ } if ( z >= ( 1L << 1 ) ) { - z >>= 1; + /* z >>= 1; */ shift += 1; } @@ -816,6 +816,8 @@ } +#if 0 + /* documentation is in ftcalc.h */ FT_BASE_DEF( FT_Int32 ) @@ -850,6 +852,8 @@ return (FT_Int32)root; } +#endif /* 0 */ + /* documentation is in ftcalc.h */ @@ -945,11 +949,27 @@ FT_Pos d_in, d_out, d_corner; + /* We approximate the Euclidean metric (sqrt(x^2 + y^2)) with */ + /* the Taxicab metric (|x| + |y|), which can be computed much */ + /* faster. If one of the two vectors is much longer than the */ + /* other one, the direction of the shorter vector doesn't */ + /* influence the result any more. */ + /* */ + /* corner */ + /* x---------------------------x */ + /* \ / */ + /* \ / */ + /* in \ / out */ + /* \ / */ + /* o */ + /* Point */ + /* */ + if ( ax < 0 ) ax = -ax; if ( ay < 0 ) ay = -ay; - d_in = ax + ay; + d_in = ax + ay; /* d_in = || in || */ ax = out_x; if ( ax < 0 ) @@ -957,7 +977,7 @@ ay = out_y; if ( ay < 0 ) ay = -ay; - d_out = ax + ay; + d_out = ax + ay; /* d_out = || out || */ ax = out_x + in_x; if ( ax < 0 ) @@ -965,7 +985,11 @@ ay = out_y + in_y; if ( ay < 0 ) ay = -ay; - d_corner = ax + ay; + d_corner = ax + ay; /* d_corner = || in + out || */ + + /* now do a simple length comparison: */ + /* */ + /* d_in + d_out < 17/16 d_corner */ return ( d_in + d_out - d_corner ) < ( d_corner >> 4 ); } |