cpml/cpml-pair.h

   1 /* CPML - Cairo Path Manipulation Library
   2  * Copyright (C) 2008, Nicola Fontana <ntd at entidi.it>
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General Public
  15  * License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
  17  * Boston, MA  02110-1301, USA.
  18  */
  19
  20 #ifndef __CPML_PAIR_H__
  21 #define __CPML_PAIR_H__
  22
  23 #include <cairo.h>
  24 #include <math.h>
  25
  26 #define CPML_DIR_RIGHT   0.
  27 #define CPML_DIR_DOWN    (M_PI/2.)
  28 #define CPML_DIR_LEFT    M_PI
  29 #define CPML_DIR_UP      (M_PI*3./2.)
  30
  31
  32 CAIRO_BEGIN_DECLS
  33
  34
  35 typedef struct _CpmlPair        CpmlPair;
  36
  37 struct _CpmlPair {
  38         double                  x, y;
  39 };
  40
  41
  42 cairo_bool_t    cpml_pair_copy                  (CpmlPair       *pair,
  43                                                  const CpmlPair *src);
  44 cairo_bool_t    cpml_pair_distance              (double         *distance,
  45                                                  const CpmlPair *from,
  46                                                  const CpmlPair *to);
  47 cairo_bool_t    cpml_pair_square_distance       (double         *distance,
  48                                                  const CpmlPair *from,
  49                                                  const CpmlPair *to);
  50 cairo_bool_t    cpml_pair_angle                 (double         *angle,
  51                                                  const CpmlPair *from,
  52                                                  const CpmlPair *to);
  53 cairo_bool_t    cpml_vector_from_pair           (CpmlPair       *vector,
  54                                                  const CpmlPair *pair);
  55 cairo_bool_t    cpml_vector_from_angle          (CpmlPair       *vector,
  56                                                  double          angle);
  57
  58
  59 CAIRO_END_DECLS
  60
  61
  62 #endif /* __CPML_PAIR_H__ */