pyx/style.py

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