libgeda/src/m_basic.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., 59 Temple Place, Suite 330, Boston, MA 02111 USA
  19  */
  20 #include <config.h>
  21
  22 #include <stdio.h>
  23 #include <math.h>
  24
  25 #include "libgeda_priv.h"
  26
  27 #ifdef HAVE_LIBDMALLOC
  28 #include <dmalloc.h>
  29 #endif
  30
  31
  32 /*! \brief Set the contraints for the current page.
  33  *  \par Function Description
  34  *  This function will set the current page constraints.
  35  *
  36  *  \param [in]     toplevel  The TOPLEVEL object.
  37  *  \param [in,out] page       The PAGE object to set constraints on.
  38  *  \param [in]     xmin       The minimum x coordinate for the page.
  39  *  \param [in]     xmax       The maximum x coordinate for the page.
  40  *  \param [in]     ymin       The minimum y coordinate for the page.
  41  *  \param [in]     ymax       The maximum y coordinate for the page.
  42  */
  43 void set_window(TOPLEVEL *toplevel, PAGE *page,
  44                 int xmin, int xmax, int ymin, int ymax)
  45 {
  46   double fs,f0,f1;
  47   double fw0,fw1,fw;
  48
  49   page->left   = xmin;
  50   page->right  = xmax;
  51   page->top    = ymin;
  52   page->bottom = ymax;
  53
  54   /* now do the constant setups */
  55
  56   /* pix_x */
  57   f0 = page->left;
  58   f1 = page->right;
  59   fs = toplevel->width;
  60   page->to_screen_x_constant = fs / (f1 - f0);
  61
  62   /* pix_y */
  63   f0 = page->top;
  64   f1 = page->bottom;
  65   fs = toplevel->height;
  66   page->to_screen_y_constant = fs / (f1 - f0);
  67
  68   /* mil_x */
  69   fw1 = page->right;
  70   fw0 = page->left;
  71   fw  = toplevel->width;
  72   page->to_world_x_constant = (fw1 - fw0) / fw;
  73
  74   /* mil_y */
  75   fw1 = page->bottom;
  76   fw0 = page->top;
  77   fw  = toplevel->height;
  78   page->to_world_y_constant = (fw1 - fw0) / fw;
  79 }
  80
  81
  82 /*! \brief Rotate a point by an arbitrary angle.
  83  *  \par Function Description
  84  *  This function will rotate a point coordinate by an arbitrary angle
  85  *  and return the new coordinate in the newx and newy parameters.
  86  *
  87  *  \param [in]  x      Input point x coordinate.
  88  *  \param [in]  y      Input point y coordinate.
  89  *  \param [in]  angle  Angle to rotate in degrees.
  90  *  \param [out] newx   Output point x coordinate.
  91  *  \param [out] newy   Output point y coordinate.
  92  */
  93 void rotate_point(int x, int y, int angle, int *newx, int *newy)
  94 {
  95   double costheta, sintheta;
  96   double rad;
  97
  98   rad = angle*M_PI/180;
  99
 100   costheta = cos(rad);
 101   sintheta = sin(rad);
 102
 103   *newx = x * costheta - y * sintheta;
 104   *newy = x * sintheta + y * costheta;
 105 }
 106
 107 /*! \brief Rotate point in 90 degree increments only.
 108  *  \par Function Description
 109  *  This function takes a point coordinate and rotates it by
 110  *  90 degrees at a time.  The new point coordinate is returned
 111  *  in newx and newy.
 112  *
 113  *  \param [in]  x      Input point x coordinate.
 114  *  \param [in]  y      Input point y coordinate.
 115  *  \param [in]  angle  Angle to rotate by (90 degree increments only).
 116  *  \param [out] newx   Output point x coordinate.
 117  *  \param [out] newy   Output point y coordinate.
 118  */
 119 void rotate_point_90(int x, int y, int angle, int *newx, int *newy)
 120 {
 121   double costheta=1;
 122   double sintheta=0;
 123
 124   /* I could have used sine/cosine for this, but I want absolute
 125    * accuracy */
 126   switch(angle) {
 127
 128     case(0):
 129       *newx = x;
 130       *newy = y;
 131       return;
 132       break;
 133
 134     case(90):
 135       costheta = 0;
 136       sintheta = 1;
 137       break;
 138
 139     case(180):
 140       costheta = -1;
 141       sintheta = 0;
 142       break;
 143
 144     case(270):
 145       costheta = 0;
 146       sintheta = -1;
 147       break;
 148   }
 149
 150   *newx = x * costheta - y * sintheta;
 151   *newy = x * sintheta + y * costheta;
 152 }
 153
 154
 155 /*! \brief Convert Paper size to World coordinates.
 156  *  \par Function Description
 157  *  This function takes the paper size and converts it to
 158  *  world coordinates. It supports landscape with a fixed aspect ratio.
 159  *
 160  *  \param [in]  width   Paper width. (units?)
 161  *  \param [in]  height  Paper height. (units?)
 162  *  \param [in]  border  Paper border size. (units?)
 163  *  \param [out] right   Right world coordinate. (units?)
 164  *  \param [out] bottom  Bottom world coordinate. (units?)
 165  *
 166  *  \todo Support more modes than just landscape only mode.
 167  */
 168 void PAPERSIZEtoWORLD(int width, int height, int border, int *right, int *bottom)
 169 {
 170   float aspect;
 171
 172   aspect = (float) width / (float) height;
 173
 174 #if DEBUG
 175   printf("%f\n", aspect);
 176 #endif
 177
 178   if (aspect < 1.333333333) {
 179     /* is this lrint really needed? */
 180 #ifdef HAVE_LRINT
 181     *right = lrint (width+border + ((height+border)*1.33333333 - (width+border)));
 182 #else
 183     *right = (int) width+border +
 184       ((height+border)*1.33333333 - (width+border));
 185 #endif
 186     *bottom = height+border;
 187   } else {
 188     *right = (int) width+border;
 189     *bottom = (int) height+border + ((width+border)/1.33333333 - (height+border));
 190   }
 191
 192 #if DEBUG
 193   aspect = (float) *right / (float) *bottom;
 194   printf("%f\n", aspect);
 195 #endif
 196
 197 }