libgeda/src/m_bounds.c

   1 /* gEDA - GPL Electronic Design Automation
   2  * libgeda - gEDA's library
   3  * Copyright (C) 1998-2010 Ales Hvezda
   4  * Copyright (C) 1998-2010 gEDA Contributors (see ChangeLog for details)
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License as published by
   8  * the Free Software Foundation; either version 2 of the License, or
   9  * (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14  * GNU General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, write to the Free Software
  18  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  19  */
  20 #include <config.h>
  21 #include <libgeda_priv.h>
  22
  23 /*! \brief Initialize a bounds by setting it to empty
  24  *
  25  *  \param bounds [in] The bounds to set to empty.  This parameter must not
  26  *  be NULL.
  27  */
  28 void m_bounds_init(BOUNDS *bounds)
  29 {
  30   bounds->min_x = G_MAXINT;
  31   bounds->min_y = G_MAXINT;
  32   bounds->max_x = G_MININT;
  33   bounds->max_y = G_MININT;
  34 }
  35
  36 /*! \brief Calculate the bounds of a set of points
  37  *
  38  *  For an empty set of points, this function returns an empty bounds.
  39  *
  40  *  \param bounds [out] The bounds of the given set of points.  The bounds
  41  *  does not need to be initialized before calling this function, but this
  42  *  parameter must not be NULL.
  43  *  \param points [in] The given set of points.  If the count is greater than
  44  *  zero, this parameter must not be NULL.
  45  *  \param count [in] The number of points in the set.
  46  */
  47 void m_bounds_of_points(BOUNDS *bounds, sPOINT points[], gint count)
  48 {
  49   gint index;
  50
  51   m_bounds_init(bounds);
  52
  53   for (index=0; index<count; index++) {
  54     gint x = points[index].x;
  55     gint y = points[index].y;
  56
  57     if (x < bounds->min_x) {
  58       bounds->min_x = x;
  59     }
  60
  61     if (y < bounds->min_y) {
  62       bounds->min_y = y;
  63     }
  64
  65     if (x > bounds->max_x) {
  66       bounds->max_x = x;
  67     }
  68
  69     if (y > bounds->max_y) {
  70       bounds->max_y = y;
  71     }
  72   }
  73 }
  74