zenilib: zenilib/jni/external/freetype2/include/freetype/internal/ftcalc.h Source File

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ftcalc.h
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1 /***************************************************************************/
2 /* */
3 /* ftcalc.h */
4 /* */
5 /* Arithmetic computations (specification). */
6 /* */
7 /* Copyright 1996-2001, 2002, 2003, 2004, 2005, 2006, 2008, 2009 by */
8 /* David Turner, Robert Wilhelm, and Werner Lemberg. */
9 /* */
10 /* This file is part of the FreeType project, and may only be used, */
11 /* modified, and distributed under the terms of the FreeType project */
12 /* license, LICENSE.TXT. By continuing to use, modify, or distribute */
13 /* this file you indicate that you have read the license and */
14 /* understand and accept it fully. */
15 /* */
16 /***************************************************************************/
17
18
19 #ifndef __FTCALC_H__
20 #define __FTCALC_H__
21
22
23 #include <ft2build.h>
24 #include FT_FREETYPE_H
25
26
27 FT_BEGIN_HEADER
28
29
30 /*************************************************************************/
31 /* */
32 /* <Function> */
33 /* FT_FixedSqrt */
34 /* */
35 /* <Description> */
36 /* Computes the square root of a 16.16 fixed point value. */
37 /* */
38 /* <Input> */
39 /* x :: The value to compute the root for. */
40 /* */
41 /* <Return> */
42 /* The result of `sqrt(x)'. */
43 /* */
44 /* <Note> */
45 /* This function is not very fast. */
46 /* */
47 FT_BASE( FT_Int32 )
48 FT_SqrtFixed( FT_Int32 x );
49
50
51 #ifdef FT_CONFIG_OPTION_OLD_INTERNALS
52
53 /*************************************************************************/
54 /* */
55 /* <Function> */
56 /* FT_Sqrt32 */
57 /* */
58 /* <Description> */
59 /* Computes the square root of an Int32 integer (which will be */
60 /* handled as an unsigned long value). */
61 /* */
62 /* <Input> */
63 /* x :: The value to compute the root for. */
64 /* */
65 /* <Return> */
66 /* The result of `sqrt(x)'. */
67 /* */
68 FT_EXPORT( FT_Int32 )
69 FT_Sqrt32( FT_Int32 x );
70
71 #endif /* FT_CONFIG_OPTION_OLD_INTERNALS */
72
73
74 /*************************************************************************/
75 /* */
76 /* FT_MulDiv() and FT_MulFix() are declared in freetype.h. */
77 /* */
78 /*************************************************************************/
79
80
81 #ifdef TT_USE_BYTECODE_INTERPRETER
82
83 /*************************************************************************/
84 /* */
85 /* <Function> */
86 /* FT_MulDiv_No_Round */
87 /* */
88 /* <Description> */
89 /* A very simple function used to perform the computation `(a*b)/c' */
90 /* (without rounding) with maximal accuracy (it uses a 64-bit */
91 /* intermediate integer whenever necessary). */
92 /* */
93 /* This function isn't necessarily as fast as some processor specific */
94 /* operations, but is at least completely portable. */
95 /* */
96 /* <Input> */
97 /* a :: The first multiplier. */
98 /* b :: The second multiplier. */
99 /* c :: The divisor. */
100 /* */
101 /* <Return> */
102 /* The result of `(a*b)/c'. This function never traps when trying to */
103 /* divide by zero; it simply returns `MaxInt' or `MinInt' depending */
104 /* on the signs of `a' and `b'. */
105 /* */
106 FT_BASE( FT_Long )
107 FT_MulDiv_No_Round( FT_Long a,
108 FT_Long b,
109 FT_Long c );
110
111 #endif /* TT_USE_BYTECODE_INTERPRETER */
112
113
114 /*
115 * A variant of FT_Matrix_Multiply which scales its result afterwards.
116 * The idea is that both `a' and `b' are scaled by factors of 10 so that
117 * the values are as precise as possible to get a correct result during
118 * the 64bit multiplication. Let `sa' and `sb' be the scaling factors of
119 * `a' and `b', respectively, then the scaling factor of the result is
120 * `sa*sb'.
121 */
122 FT_BASE( void )
123 FT_Matrix_Multiply_Scaled( const FT_Matrix* a,
124 FT_Matrix *b,
125 FT_Long scaling );
126
127
128 /*
129 * A variant of FT_Vector_Transform. See comments for
130 * FT_Matrix_Multiply_Scaled.
131 */
132
133 FT_BASE( void )
134 FT_Vector_Transform_Scaled( FT_Vector* vector,
135 const FT_Matrix* matrix,
136 FT_Long scaling );
137
138
139 /*
140 * Return -1, 0, or +1, depending on the orientation of a given corner.
141 * We use the Cartesian coordinate system, with positive vertical values
142 * going upwards. The function returns +1 if the corner turns to the
143 * left, -1 to the right, and 0 for undecidable cases.
144 */
145 FT_BASE( FT_Int )
146 ft_corner_orientation( FT_Pos in_x,
147 FT_Pos in_y,
148 FT_Pos out_x,
149 FT_Pos out_y );
150
151 /*
152 * Return TRUE if a corner is flat or nearly flat. This is equivalent to
153 * saying that the angle difference between the `in' and `out' vectors is
154 * very small.
155 */
156 FT_BASE( FT_Int )
157 ft_corner_is_flat( FT_Pos in_x,
158 FT_Pos in_y,
159 FT_Pos out_x,
160 FT_Pos out_y );
161
162
163 #define INT_TO_F26DOT6( x ) ( (FT_Long)(x) << 6 )
164 #define INT_TO_F2DOT14( x ) ( (FT_Long)(x) << 14 )
165 #define INT_TO_FIXED( x ) ( (FT_Long)(x) << 16 )
166 #define F2DOT14_TO_FIXED( x ) ( (FT_Long)(x) << 2 )
167 #define FLOAT_TO_FIXED( x ) ( (FT_Long)( x * 65536.0 ) )
168 #define FIXED_TO_INT( x ) ( FT_RoundFix( x ) >> 16 )
169
170 #define ROUND_F26DOT6( x ) ( x >= 0 ? ( ( (x) + 32 ) & -64 ) \
171 : ( -( ( 32 - (x) ) & -64 ) ) )
172
173
174 FT_END_HEADER
175
176 #endif /* __FTCALC_H__ */
177
178
179 /* END */
FT_Long
signed long FT_Long
Definition: fttypes.h:238
FT_Pos
FT_BEGIN_HEADER typedef signed long FT_Pos
Definition: ftimage.h:59
FT_END_HEADER
#define FT_END_HEADER
Definition: ftheader.h:54
FT_Int
signed int FT_Int
Definition: fttypes.h:216
FT_Matrix_
Definition: fttypes.h:381
x
EGLSurface EGLint x
Definition: eglext.h:293
a
GLboolean GLboolean GLboolean GLboolean a
Definition: glew.h:8736
ft_corner_is_flat
ft_corner_is_flat(FT_Pos in_x, FT_Pos in_y, FT_Pos out_x, FT_Pos out_y)
Definition: ftcalc.c:921
FT_BEGIN_HEADER
#define FT_BEGIN_HEADER
Definition: ftheader.h:36
c
const GLfloat * c
Definition: glew.h:14913
FT_Vector_
Definition: ftimage.h:75
matrix
GLuint GLenum matrix
Definition: glew.h:13408
FT_SqrtFixed
FT_BEGIN_HEADER FT_SqrtFixed(FT_Int32 x)
Definition: ftcalc.c:806
ft_corner_orientation
ft_corner_orientation(FT_Pos in_x, FT_Pos in_y, FT_Pos out_x, FT_Pos out_y)
Definition: ftcalc.c:841
FT_Vector_Transform_Scaled
FT_Vector_Transform_Scaled(FT_Vector *vector, const FT_Matrix *matrix, FT_Long scaling)
Definition: ftcalc.c:780
const
#define const
Definition: zconf.h:91
ft2build.h
FT_EXPORT
#define FT_EXPORT(x)
Definition: ftconfig.h:500
FT_Matrix_Multiply_Scaled
FT_Matrix_Multiply_Scaled(const FT_Matrix *a, FT_Matrix *b, FT_Long scaling)
Definition: ftcalc.c:755
b
GLdouble GLdouble GLdouble b
Definition: glew.h:8383
FT_BASE
#define FT_BASE(x)
Definition: ftconfig.h:478