pyx/style.py

   1 #!/usr/bin/env python
   2 # -*- coding: ISO-8859-1 -*-
   3 #
   4 #
   5 # Copyright (C) 2002, 2003 Jörg Lehmann <joergl@users.sourceforge.net>
   6 # Copyright (C) 2003 Michael Schindler <m-schindler@users.sourceforge.net>
   7 # Copyright (C) 2002, 2003 André Wobst <wobsta@users.sourceforge.net>
   8 #
   9 # This file is part of PyX (http://pyx.sourceforge.net/).
  10 #
  11 # PyX is free software; you can redistribute it and/or modify
  12 # it under the terms of the GNU General Public License as published by
  13 # the Free Software Foundation; either version 2 of the License, or
  14 # (at your option) any later version.
  15 #
  16 # PyX is distributed in the hope that it will be useful,
  17 # but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 # GNU General Public License for more details.
  20 #
  21 # You should have received a copy of the GNU General Public License
  22 # along with PyX; if not, write to the Free Software
  23 # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  24
  25 import math
  26 import attr, unit, base
  27
  28 #
  29 # base classes for stroke and fill styles
  30 #
  31
  32 class strokestyle(base.PSOp): pass
  33
  34 class fillstyle(base.PSOp): pass
  35
  36 #
  37 # common stroke styles
  38 #
  39
  40
  41 class linecap(attr.exclusiveattr, strokestyle):
  42
  43     """linecap of paths"""
  44
  45     def __init__(self, value=0):
  46         attr.exclusiveattr.__init__(self, linecap)
  47         self.value = value
  48
  49     def write(self, file):
  50         file.write("%d setlinecap\n" % self.value)
  51
  52 linecap.butt = linecap(0)
  53 linecap.round = linecap(1)
  54 linecap.square = linecap(2)
  55 linecap.clear = attr.clearclass(linecap)
  56
  57
  58 class linejoin(attr.exclusiveattr, strokestyle):
  59
  60     """linejoin of paths"""
  61
  62     def __init__(self, value=0):
  63         attr.exclusiveattr.__init__(self, linejoin)
  64         self.value = value
  65
  66     def write(self, file):
  67         file.write("%d setlinejoin\n" % self.value)
  68
  69 linejoin.miter = linejoin(0)
  70 linejoin.round = linejoin(1)
  71 linejoin.bevel = linejoin(2)
  72 linejoin.clear = attr.clearclass(linejoin)
  73
  74
  75 class miterlimit(attr.exclusiveattr, strokestyle):
  76
  77     """miterlimit of paths"""
  78
  79     def __init__(self, value=10.0):
  80         attr.exclusiveattr.__init__(self, miterlimit)
  81         self.value = value
  82
  83     def write(self, file):
  84         file.write("%f setmiterlimit\n" % self.value)
  85
  86 miterlimit.lessthan180deg = miterlimit(1/math.sin(math.pi*180/360))
  87 miterlimit.lessthan90deg = miterlimit(1/math.sin(math.pi*90/360))
  88 miterlimit.lessthan60deg = miterlimit(1/math.sin(math.pi*60/360))
  89 miterlimit.lessthan45deg = miterlimit(1/math.sin(math.pi*45/360))
  90 miterlimit.lessthan11deg = miterlimit(10) # the default, approximately 11.4783 degress
  91 miterlimit.clear = attr.clearclass(miterlimit)
  92
  93
  94 class dash(attr.exclusiveattr, strokestyle):
  95
  96     """dash of paths"""
  97
  98     def __init__(self, pattern=[], offset=0, rellengths=0):
  99         """set pattern with offset.
 100
 101         If rellengths is True, interpret all dash lengths relative to current linewidth.
 102         """
 103         attr.exclusiveattr.__init__(self, dash)
 104         self.pattern = pattern
 105         self.offset = offset
 106         self.rellengths = rellengths
 107
 108     def write(self, file):
 109         if self.rellengths:
 110             sep = " currentlinewidth mul "
 111         else:
 112             sep = " "
 113         patternstring = sep.join(["%g" % element for element in self.pattern])
 114         file.write("[%s] %d setdash\n" % (patternstring, self.offset))
 115
 116 dash.clear = attr.clearclass(dash)
 117
 118
 119 class linestyle(attr.exclusiveattr, strokestyle):
 120
 121     """linestyle (linecap together with dash) of paths"""
 122
 123     def __init__(self, c=linecap.butt, d=dash([])):
 124         # XXX better, but at the moment not supported by attr.exlusiveattr would be:
 125         # XXX   attr.exclusiveattr.__init__(self, [linestyle, linecap, dash])
 126         attr.exclusiveattr.__init__(self, linestyle)
 127         self.c = c
 128         self.d = d
 129
 130     def write(self, file):
 131         self.c.write(file)
 132         self.d.write(file)
 133
 134 linestyle.solid = linestyle(linecap.butt, dash([]))
 135 linestyle.dashed = linestyle(linecap.butt, dash([2]))
 136 linestyle.dotted = linestyle(linecap.round, dash([0, 3]))
 137 linestyle.dashdotted = linestyle(linecap.round, dash([0, 3, 3, 3]))
 138 linestyle.clear = attr.clearclass(linestyle)
 139
 140
 141 class linewidth(unit.length, attr.exclusiveattr, attr.sortbeforeattr, strokestyle):
 142
 143     """linewidth of paths"""
 144
 145     def __init__(self, l="0 cm"):
 146         unit.length.__init__(self, l=l, default_type="w")
 147         attr.exclusiveattr.__init__(self, linewidth)
 148         attr.sortbeforeattr.__init__(self, [dash, linestyle])
 149
 150     def merge(self, attrs):
 151         return attr.sortbeforeattr.merge(self, attr.exclusiveattr.merge(self, attrs))
 152
 153     def write(self, file):
 154         file.write("%f setlinewidth\n" % unit.topt(self))
 155
 156 _base = 0.02
 157
 158 linewidth.THIN = linewidth("%f cm" % (_base/math.sqrt(32)))
 159 linewidth.THIn = linewidth("%f cm" % (_base/math.sqrt(16)))
 160 linewidth.THin = linewidth("%f cm" % (_base/math.sqrt(8)))
 161 linewidth.Thin = linewidth("%f cm" % (_base/math.sqrt(4)))
 162 linewidth.thin = linewidth("%f cm" % (_base/math.sqrt(2)))
 163 linewidth.normal = linewidth("%f cm" % _base)
 164 linewidth.thick = linewidth("%f cm" % (_base*math.sqrt(2)))
 165 linewidth.Thick = linewidth("%f cm" % (_base*math.sqrt(4)))
 166 linewidth.THick = linewidth("%f cm" % (_base*math.sqrt(8)))
 167 linewidth.THIck = linewidth("%f cm" % (_base*math.sqrt(16)))
 168 linewidth.THICk = linewidth("%f cm" % (_base*math.sqrt(32)))
 169 linewidth.THICK = linewidth("%f cm" % (_base*math.sqrt(64)))
 170 linewidth.clear = attr.clearclass(linewidth)