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src/java.desktop/share/native/libfreetype/src/base/fttrigon.c
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@@ -1,35 +1,35 @@
-/***************************************************************************/
-/* */
-/* 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
#include FT_INTERNAL_CALC_H
#include FT_TRIGONOMETRY_H
@@ -323,14 +323,14 @@
/* documentation is in fttrigon.h */
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 );
}
@@ -370,18 +370,10 @@
vec->x = ( vec->x + 0x80L ) >> 8;
vec->y = ( vec->y + 0x80L ) >> 8;
}
- /* 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 )
FT_Vector_Rotate( FT_Vector* vec,
FT_Angle angle )
@@ -406,12 +398,12 @@
if ( shift > 0 )
{
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
{
shift = -shift;
vec->x = (FT_Pos)( (FT_ULong)v.x << shift );
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