pyx/style.py

   1 # -*- coding: ISO-8859-1 -*-
   2 #
   3 #
   4 # Copyright (C) 2002-2006 Jörg Lehmann <joergl@users.sourceforge.net>
   5 # Copyright (C) 2003-2004,2006 Michael Schindler <m-schindler@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., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
  23
  24 import math
  25 import attr, unit, canvas
  26
  27 #
  28 # base classes for stroke and fill styles
  29 #
  30
  31 class strokestyle(canvas.canvasitem): pass
  32
  33 class fillstyle(canvas.canvasitem): pass
  34
  35 #
  36 # common stroke styles
  37 #
  38
  39
  40 class linecap(attr.exclusiveattr, strokestyle):
  41
  42     """linecap of paths"""
  43
  44     def __init__(self, value=0):
  45         attr.exclusiveattr.__init__(self, linecap)
  46         self.value = value
  47
  48     def processPS(self, file, writer, context, registry, bbox):
  49         file.write("%d setlinecap\n" % self.value)
  50
  51     def processPDF(self, file, writer, context, registry, bbox):
  52         file.write("%d J\n" % self.value)
  53
  54 linecap.butt = linecap(0)
  55 linecap.round = linecap(1)
  56 linecap.square = linecap(2)
  57 linecap.clear = attr.clearclass(linecap)
  58
  59
  60 class linejoin(attr.exclusiveattr, strokestyle):
  61
  62     """linejoin of paths"""
  63
  64     def __init__(self, value=0):
  65         attr.exclusiveattr.__init__(self, linejoin)
  66         self.value = value
  67
  68     def processPS(self, file, writer, context, registry, bbox):
  69         file.write("%d setlinejoin\n" % self.value)
  70
  71     def processPDF(self, file, writer, context, registry, bbox):
  72         file.write("%d j\n" % self.value)
  73
  74 linejoin.miter = linejoin(0)
  75 linejoin.round = linejoin(1)
  76 linejoin.bevel = linejoin(2)
  77 linejoin.clear = attr.clearclass(linejoin)
  78
  79
  80 class miterlimit(attr.exclusiveattr, strokestyle):
  81
  82     """miterlimit of paths"""
  83
  84     def __init__(self, value=10.0):
  85         attr.exclusiveattr.__init__(self, miterlimit)
  86         self.value = value
  87
  88     def processPS(self, file, writer, context, registry, bbox):
  89         file.write("%f setmiterlimit\n" % self.value)
  90
  91     def processPDF(self, file, writer, context, registry, bbox):
  92         file.write("%f M\n" % self.value)
  93
  94 miterlimit.lessthan180deg = miterlimit(1/math.sin(math.pi*180/360))
  95 miterlimit.lessthan90deg = miterlimit(1/math.sin(math.pi*90/360))
  96 miterlimit.lessthan60deg = miterlimit(1/math.sin(math.pi*60/360))
  97 miterlimit.lessthan45deg = miterlimit(1/math.sin(math.pi*45/360))
  98 miterlimit.lessthan11deg = miterlimit(10) # the default, approximately 11.4783 degress
  99 miterlimit.clear = attr.clearclass(miterlimit)
 100
 101
 102 _defaultlinewidth = 0.02 * unit.w_cm
 103 _defaultlinewidth_pt = unit.topt(_defaultlinewidth)
 104
 105 class dash(attr.exclusiveattr, strokestyle):
 106
 107     """dash of paths"""
 108
 109     def __init__(self, pattern=[], offset=0, rellengths=1):
 110         """set pattern with offset.
 111
 112         If rellengths is True, interpret all dash lengths relative to current linewidth.
 113         """
 114         attr.exclusiveattr.__init__(self, dash)
 115         self.pattern = pattern
 116         self.offset = offset
 117         self.rellengths = rellengths
 118
 119     def processPS(self, file, writer, context, registry, bbox):
 120         if self.rellengths:
 121             patternstring = " ".join(["%f" % (element * context.linewidth_pt/_defaultlinewidth_pt) for element in self.pattern])
 122         else:
 123             patternstring = " ".join(["%f" % element for element in self.pattern])
 124         file.write("[%s] %d setdash\n" % (patternstring, self.offset))
 125
 126     def processPDF(self, file, writer, context, registry, bbox):
 127         if self.rellengths:
 128             patternstring = " ".join(["%f" % (element * context.linewidth_pt/_defaultlinewidth_pt) for element in self.pattern])
 129         else:
 130             patternstring = " ".join(["%f" % element for element in self.pattern])
 131         file.write("[%s] %d d\n" % (patternstring, self.offset))
 132
 133 dash.clear = attr.clearclass(dash)
 134
 135
 136 class linestyle(attr.exclusiveattr, strokestyle):
 137
 138     """linestyle (linecap together with dash) of paths"""
 139
 140     def __init__(self, c=linecap.butt, d=dash([])):
 141         # XXX better, but at the moment not supported by attr.exlusiveattr would be:
 142         # XXX   attr.exclusiveattr.__init__(self, [linestyle, linecap, dash])
 143         attr.exclusiveattr.__init__(self, linestyle)
 144         self.c = c
 145         self.d = d
 146
 147     def processPS(self, file, writer, context, registry, bbox):
 148         self.c.processPS(file, writer, context, registry, bbox)
 149         self.d.processPS(file, writer, context, registry, bbox)
 150
 151     def processPDF(self, file, writer, context, registry, bbox):
 152         self.c.processPDF(file, writer, context, registry, bbox)
 153         self.d.processPDF(file, writer, context, registry, bbox)
 154
 155 linestyle.solid = linestyle(linecap.butt, dash([]))
 156 linestyle.dashed = linestyle(linecap.butt, dash([2]))
 157 linestyle.dotted = linestyle(linecap.round, dash([0, 2]))
 158 linestyle.dashdotted = linestyle(linecap.round, dash([0, 2, 2, 2]))
 159 linestyle.clear = attr.clearclass(linestyle)
 160
 161
 162 class linewidth(attr.sortbeforeexclusiveattr, strokestyle):
 163
 164     """linewidth of paths"""
 165
 166     def __init__(self, width):
 167         attr.sortbeforeexclusiveattr.__init__(self, linewidth, [dash, linestyle])
 168         self.width = width
 169
 170     def processPS(self, file, writer, context, registry, bbox):
 171         file.write("%f setlinewidth\n" % unit.topt(self.width))
 172         context.linewidth_pt = unit.topt(self.width)
 173
 174     def processPDF(self, file, writer, context, registry, bbox):
 175         file.write("%f w\n" % unit.topt(self.width))
 176         context.linewidth_pt = unit.topt(self.width)
 177
 178 linewidth.THIN = linewidth(_defaultlinewidth/math.sqrt(32))
 179 linewidth.THIn = linewidth(_defaultlinewidth/math.sqrt(16))
 180 linewidth.THin = linewidth(_defaultlinewidth/math.sqrt(8))
 181 linewidth.Thin = linewidth(_defaultlinewidth/math.sqrt(4))
 182 linewidth.thin = linewidth(_defaultlinewidth/math.sqrt(2))
 183 linewidth.normal = linewidth(_defaultlinewidth)
 184 linewidth.thick = linewidth(_defaultlinewidth*math.sqrt(2))
 185 linewidth.Thick = linewidth(_defaultlinewidth*math.sqrt(4))
 186 linewidth.THick = linewidth(_defaultlinewidth*math.sqrt(8))
 187 linewidth.THIck = linewidth(_defaultlinewidth*math.sqrt(16))
 188 linewidth.THICk = linewidth(_defaultlinewidth*math.sqrt(32))
 189 linewidth.THICK = linewidth(_defaultlinewidth*math.sqrt(64))
 190 linewidth.clear = attr.clearclass(linewidth)