pyx/bbox.py

   1 #!/usr/bin/env python
   2 # -*- coding: ISO-8859-1 -*-
   3 #
   4 #
   5 # Copyright (C) 2002-2004 Jörg Lehmann <joergl@users.sourceforge.net>
   6 # Copyright (C) 2002-2004 André Wobst <wobsta@users.sourceforge.net>
   7 #
   8 # This file is part of PyX (http://pyx.sourceforge.net/).
   9 #
  10 # PyX is free software; you can redistribute it and/or modify
  11 # it under the terms of the GNU General Public License as published by
  12 # the Free Software Foundation; either version 2 of the License, or
  13 # (at your option) any later version.
  14 #
  15 # PyX is distributed in the hope that it will be useful,
  16 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  17 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  18 # GNU General Public License for more details.
  19 #
  20 # You should have received a copy of the GNU General Public License
  21 # along with PyX; if not, write to the Free Software
  22 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  23
  24 import math
  25 import unit
  26
  27 #
  28 # classes representing bounding boxes
  29 #
  30
  31 class _bbox:
  32
  33     """class for bounding boxes
  34
  35     This variant requires points in the constructor, and is used for internal
  36     purposes."""
  37
  38     def __init__(self, llx, lly, urx, ury):
  39         self.llx = llx
  40         self.lly = lly
  41         self.urx = urx
  42         self.ury = ury
  43
  44     def __add__(self, other):
  45         """join two bboxes"""
  46         return _bbox(min(self.llx, other.llx), min(self.lly, other.lly),
  47                      max(self.urx, other.urx), max(self.ury, other.ury))
  48
  49     def __iadd__(self, other):
  50         """join two bboxes inplace"""
  51         self.llx = min(self.llx, other.llx)
  52         self.lly = min(self.lly, other.lly)
  53         self.urx = max(self.urx, other.urx)
  54         self.ury = max(self.ury, other.ury)
  55         return self
  56
  57     def __mul__(self, other):
  58         """return intersection of two bboxes"""
  59         return _bbox(max(self.llx, other.llx), max(self.lly, other.lly),
  60                      min(self.urx, other.urx), min(self.ury, other.ury))
  61
  62     def __imul__(self, other):
  63         """intersect two bboxes in place"""
  64         self.llx = max(self.llx, other.llx)
  65         self.lly = max(self.lly, other.lly)
  66         self.urx = min(self.urx, other.urx)
  67         self.ury = min(self.ury, other.ury)
  68         return self
  69
  70     def __str__(self):
  71         return "%s %s %s %s" % (self.llx, self.lly, self.urx, self.ury)
  72
  73     def outputPS(self, file):
  74         file.write("%%%%BoundingBox: %d %d %d %d\n" %
  75                    (math.floor(self.llx), math.floor(self.lly),
  76                     math.ceil(self.urx), math.ceil(self.ury)))
  77         file.write("%%%%HiResBoundingBox: %g %g %g %g\n" %
  78                    (self.llx, self.lly, self.urx, self.ury))
  79
  80     def outputPDF(self, file):
  81         file.write("/MediaBox [%d %d %d %d]\n" %
  82                    (math.floor(self.llx), math.floor(self.lly),
  83                     math.ceil(self.urx), math.ceil(self.ury)))
  84
  85     def intersects(self, other):
  86         """check, if two bboxes intersect eachother"""
  87         return not (self.llx > other.urx or
  88                     self.lly > other.ury or
  89                     self.urx < other.llx or
  90                     self.ury < other.lly)
  91
  92     def transform(self, trafo):
  93         """transform bbox in place by trafo"""
  94         # we have to transform all four corner points of the bbox
  95         llx, lly = trafo._apply(self.llx, self.lly)
  96         lrx, lry = trafo._apply(self.urx, self.lly)
  97         urx, ury = trafo._apply(self.urx, self.ury)
  98         ulx, uly = trafo._apply(self.llx, self.ury)
  99
 100         # Now, by sorting, we obtain the lower left and upper right corner
 101         # of the new bounding box.
 102         self.llx = min(llx, lrx, urx, ulx)
 103         self.lly = min(lly, lry, ury, uly)
 104         self.urx = max(llx, lrx, urx, ulx)
 105         self.ury = max(lly, lry, ury, uly)
 106
 107     def transformed(self, trafo):
 108         """return bbox transformed by trafo"""
 109         # we have to transform all four corner points of the bbox
 110         llx, lly = trafo._apply(self.llx, self.lly)
 111         lrx, lry = trafo._apply(self.urx, self.lly)
 112         urx, ury = trafo._apply(self.urx, self.ury)
 113         ulx, uly = trafo._apply(self.llx, self.ury)
 114
 115         # Now, by sorting, we obtain the lower left and upper right corner
 116         # of the new bounding box.
 117         return _bbox(min(llx, lrx, urx, ulx), min(lly, lry, ury, uly),
 118                      max(llx, lrx, urx, ulx), max(lly, lry, ury, uly))
 119
 120     def enlarged(self, all=0, bottom=None, left=None, top=None, right=None):
 121         """enlarge bbox in place
 122
 123         all is used, if bottom, left, top and/or right are not given.
 124
 125         """
 126         _bottom = _left = _top = _right = unit.topt(unit.length(all, default_type="v"))
 127         if bottom is not None:
 128            _bottom = unit.topt(unit.length(bottom, default_type="v"))
 129         if left is not None:
 130            _left = unit.topt(unit.length(left, default_type="v"))
 131         if top is not None:
 132            _top = unit.topt(unit.length(top, default_type="v"))
 133         if right is not None:
 134            _right = unit.topt(unit.length(right, default_type="v"))
 135         self.llx -= _left
 136         self.lly -= _bottom
 137         self.urx += _right
 138         self.ury += top
 139
 140     def enlarged(self, all=0, bottom=None, left=None, top=None, right=None):
 141         """return bbox enlarged
 142
 143         all is used, if bottom, left, top and/or right are not given.
 144
 145         """
 146         _bottom = _left = _top = _right = unit.topt(unit.length(all, default_type="v"))
 147         if bottom is not None:
 148            _bottom = unit.topt(unit.length(bottom, default_type="v"))
 149         if left is not None:
 150            _left = unit.topt(unit.length(left, default_type="v"))
 151         if top is not None:
 152            _top = unit.topt(unit.length(top, default_type="v"))
 153         if right is not None:
 154            _right = unit.topt(unit.length(right, default_type="v"))
 155         return _bbox(self.llx-_left, self.lly-_bottom, self.urx+_right, self.ury+_top)
 156
 157     def rect(self):
 158         """return rectangle corresponding to bbox"""
 159         import path
 160         return path.rect_pt(self.llx, self.lly, self.urx-self.llx, self.ury-self.lly)
 161
 162     path = rect
 163
 164     def height(self):
 165         """return height of bbox"""
 166         return unit.t_pt(self.ury-self.lly)
 167
 168     def width(self):
 169         """return width of bbox"""
 170         return unit.t_pt(self.urx-self.llx)
 171
 172     def top(self):
 173         """return top coordinate of bbox"""
 174         return unit.t_pt(self.ury)
 175
 176     def bottom(self):
 177         """return bottom coordinate of bbox"""
 178         return unit.t_pt(self.lly)
 179
 180     def left(self):
 181         """return left coordinate of bbox"""
 182         return unit.t_pt(self.llx)
 183
 184     def right(self):
 185         """return right coordinate of bbox"""
 186         return unit.t_pt(self.urx)
 187
 188
 189 class bbox(_bbox):
 190
 191     """class for bounding boxes"""
 192
 193     def __init__(self, llx, lly, urx, ury):
 194         llx = unit.topt(llx)
 195         lly = unit.topt(lly)
 196         urx = unit.topt(urx)
 197         ury = unit.topt(ury)
 198         _bbox.__init__(self, llx, lly, urx, ury)
 199