share/extensions/grid_polar.py

   1 #!/usr/bin/env python
   2 '''
   3 Copyright (C) 2007 John Beard john.j.beard@gmail.com
   4
   5 ##This extension allows you to draw a polar grid in Inkscape.
   6 ##There is a wide range of options including subdivision and labels.
   7
   8 This program is free software; you can redistribute it and/or modify
   9 it under the terms of the GNU General Public License as published by
  10 the Free Software Foundation; either version 2 of the License, or
  11 (at your option) any later version.
  12
  13 This program is distributed in the hope that it will be useful,
  14 but WITHOUT ANY WARRANTY; without even the implied warranty of
  15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  16 GNU General Public License for more details.
  17
  18 You should have received a copy of the GNU General Public License
  19 along with this program; if not, write to the Free Software
  20 Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
  21 '''
  22
  23 import inkex
  24 import simplestyle, sys
  25 from math import *
  26
  27 def draw_SVG_circle(r, cx, cy, width, fill, name, parent):
  28     style = { 'stroke': '#000000', 'stroke-width':str(width), 'fill': fill }
  29     circ_attribs = {'style':simplestyle.formatStyle(style),
  30                     'cx':str(cx), 'cy':str(cy),
  31                     'r':str(r),
  32                     inkex.addNS('label','inkscape'):name}
  33     circle = inkex.etree.SubElement(parent, inkex.addNS('circle','svg'), circ_attribs )
  34
  35 def draw_SVG_line(x1, y1, x2, y2, width, name, parent):
  36     style = { 'stroke': '#000000', 'stroke-width':str(width), 'fill': 'none' }
  37     line_attribs = {'style':simplestyle.formatStyle(style),
  38                     inkex.addNS('label','inkscape'):name,
  39                     'd':'M '+str(x1)+','+str(y1)+' L '+str(x2)+','+str(y2)}
  40     inkex.etree.SubElement(parent, inkex.addNS('path','svg'), line_attribs )
  41
  42 def draw_SVG_label_centred(x, y, string, font_size, name, parent):
  43     style = {'text-align': 'center', 'vertical-align': 'top',
  44              'text-anchor': 'middle', 'font-size': str(font_size)+'px',
  45              'fill-opacity': '1.0', 'stroke': 'none',
  46              'font-weight': 'normal', 'font-style': 'normal', 'fill': '#000000'}
  47     label_attribs = {'style':simplestyle.formatStyle(style),
  48                      inkex.addNS('label','inkscape'):name,
  49                      'x':str(x), 'y':str(y)}
  50     label = inkex.etree.SubElement(parent, inkex.addNS('text','svg'), label_attribs)
  51     label.text = string
  52
  53 class Grid_Polar(inkex.Effect):
  54     def __init__(self):
  55         inkex.Effect.__init__(self)
  56         self.OptionParser.add_option("--r_divs",
  57                         action="store", type="int",
  58                         dest="r_divs", default=5,
  59                         help="Circular Divisions")
  60         self.OptionParser.add_option("--dr",
  61                         action="store", type="float",
  62                         dest="dr", default=50,
  63                         help="Circular Division Spacing")
  64         self.OptionParser.add_option("--r_subdivs",
  65                         action="store", type="int",
  66                         dest="r_subdivs", default=3,
  67                         help="Circular Subdivisions per Major division")
  68         self.OptionParser.add_option("--r_log",
  69                         action="store", type="inkbool",
  70                         dest="r_log", default=False,
  71                         help="Logarithmic subdivisions if true")
  72         self.OptionParser.add_option("--r_divs_th",
  73                         action="store", type="float",
  74                         dest="r_divs_th", default=2,
  75                         help="Major Circular Division Line thickness")
  76         self.OptionParser.add_option("--r_subdivs_th",
  77                         action="store", type="float",
  78                         dest="r_subdivs_th", default=1,
  79                         help="Minor Circular Division Line thickness")
  80         self.OptionParser.add_option("--a_divs",
  81                         action="store", type="int",
  82                         dest="a_divs", default=24,
  83                         help="Angle Divisions")
  84         self.OptionParser.add_option("--a_divs_cent",
  85                         action="store", type="int",
  86                         dest="a_divs_cent", default=4,
  87                         help="Angle Divisions at Centre")
  88         self.OptionParser.add_option("--a_subdivs",
  89                         action="store", type="int",
  90                         dest="a_subdivs", default=1,
  91                         help="Angcular Subdivisions per Major division")
  92         self.OptionParser.add_option("--a_subdivs_cent",
  93                         action="store", type="int",
  94                         dest="a_subdivs_cent", default=1,
  95                         help="Angular Subdivisions end 'n' major circular divisions before the centre")
  96         self.OptionParser.add_option("--a_divs_th",
  97                         action="store", type="float",
  98                         dest="a_divs_th", default=2,
  99                         help="Major Angular Division Line thickness")
 100         self.OptionParser.add_option("--a_subdivs_th",
 101                         action="store", type="float",
 102                         dest="a_subdivs_th", default=1,
 103                         help="Minor Angular Division Line thickness")
 104         self.OptionParser.add_option("--c_dot_dia",
 105                         action="store", type="float",
 106                         dest="c_dot_dia", default=5.0,
 107                         help="Diameter of Centre Dot")
 108         self.OptionParser.add_option("--a_labels",
 109                         action="store", type="string",
 110                         dest="a_labels", default='deg',
 111                         help="The kind of labels to apply")
 112         self.OptionParser.add_option("--a_label_size",
 113                         action="store", type="int",
 114                         dest="a_label_size", default=18,
 115                         help="The nominal pixel size of the circumferential labels")
 116         self.OptionParser.add_option("--a_label_outset",
 117                         action="store", type="float",
 118                         dest="a_label_outset", default=24,
 119                         help="The radial outset of the circumferential labels")
 120
 121     def effect(self):
 122
 123         # Embed grid in group
 124         #Put in in the centre of the current view
 125         t = 'translate(' + str( self.view_center[0] ) + ',' + str( self.view_center[1] ) + ')'
 126         g_attribs = {inkex.addNS('label','inkscape'):'Grid_Polar:R' +
 127                                  str( self.options.r_divs )+':A'+str( self.options.a_divs ),
 128                      'transform':t }
 129         grid = inkex.etree.SubElement(self.current_layer, 'g', g_attribs)
 130
 131         dr = self.options.dr                        #Distance between neighbouring circles
 132         dtheta = 2 * pi / self.options.a_divs_cent  #Angular change between adjacent radial lines at centre
 133         rmax = self.options.r_divs * dr
 134
 135         #Create SVG circles
 136         for i in range(1, self.options.r_divs+1):
 137             draw_SVG_circle(i*dr, 0, 0, #major div circles
 138                             self.options.r_divs_th, 'none',
 139                             'MajorDivCircle'+str(i)+':R'+str(i*dr), grid)
 140
 141             if self.options.r_log: #logarithmic subdivisions
 142                 for j in range (2, self.options.r_subdivs):
 143                     draw_SVG_circle(i*dr-(1-log(j, self.options.r_subdivs))*dr, #minor div circles
 144                                     0, 0, self.options.r_subdivs_th, 'none',
 145                                     'MinorDivCircle'+str(i)+':Log'+str(j), grid)
 146             else: #linear subdivs
 147                 for j in range (1, self.options.r_subdivs):
 148                     draw_SVG_circle(i*dr-j*dr/self.options.r_subdivs, #minor div circles
 149                                     0, 0, self.options.r_subdivs_th, 'none',
 150                                     'MinorDivCircle'+str(i)+':R'+str(i*dr), grid)
 151
 152         if self.options.a_divs == self.options.a_divs_cent: #the lines can go from the centre to the edge
 153             for i in range(0, self.options.a_divs):
 154                 draw_SVG_line(0, 0, rmax*sin(i*dtheta), rmax*cos(i*dtheta),
 155                               self.options.a_divs_th, 'RadialGridline'+str(i), grid)
 156
 157         else: #we need separate lines
 158             for i in range(0, self.options.a_divs_cent): #lines that go to the first circle
 159                 draw_SVG_line(0, 0, dr*sin(i*dtheta), dr*cos(i*dtheta),
 160                               self.options.a_divs_th, 'RadialGridline'+str(i), grid)
 161
 162             dtheta = 2 * pi / self.options.a_divs #work out the angle change for outer lines
 163
 164             for i in range(0, self.options.a_divs): #lines that go from there to the edge
 165                 draw_SVG_line(  dr*sin(i*dtheta+pi/2.0),   dr*cos(i*dtheta+pi/2.0),
 166                               rmax*sin(i*dtheta+pi/2.0), rmax*cos(i*dtheta+pi/2.0),
 167                               self.options.a_divs_th, 'RadialGridline'+str(i), grid)
 168
 169         if self.options.a_subdivs > 1: #draw angular subdivs
 170             for i in range(0, self.options.a_divs): #for each major divison
 171                 for j in range(1, self.options.a_subdivs): #draw the subdivisions
 172                     angle = i*dtheta-j*dtheta/self.options.a_subdivs+pi/2.0 # the angle of the subdivion line
 173                     draw_SVG_line(dr*self.options.a_subdivs_cent*sin(angle),
 174                                   dr*self.options.a_subdivs_cent*cos(angle),
 175                                   rmax*sin(angle), rmax*cos(angle),
 176                                   self.options.a_subdivs_th, 'RadialMinorGridline'+str(i), grid)
 177
 178         if self.options.c_dot_dia <> 0: #if a non-zero diameter, draw the centre dot
 179             draw_SVG_circle(self.options.c_dot_dia /2.0,
 180                             0, 0, 0, '#000000', 'CentreDot', grid)
 181
 182         if self.options.a_labels == 'deg':
 183             label_radius = rmax+self.options.a_label_outset  #radius of label centres
 184             label_size = self.options.a_label_size
 185             numeral_size = 0.73*label_size #numerals appear to be 0.73 the height of the nominal pixel size of the font in "Sans"
 186
 187             for i in range(0, self.options.a_divs):#self.options.a_divs): #radial line labels
 188                 draw_SVG_label_centred(sin(i*dtheta+pi/2.0)*label_radius,        #0 at the RHS, mathematical style
 189                                        cos(i*dtheta+pi/2.0)*label_radius+ numeral_size/2.0, #centre the text vertically
 190                                        str(i*360/self.options.a_divs),
 191                                        label_size, 'Label'+str(i), grid)
 192
 193 if __name__ == '__main__':
 194     e = Grid_Polar()
 195     e.affect()
 196
 197
 198 # vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 encoding=utf-8 textwidth=99