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index 398e877e931efe5513c556aed8111426a7f34cf5..8fee6a9960b69affcea4448c72f573d7861b0012 100644 (file)
-#!/usr/bin/env python
-'''
-Copyright (C) 2007 Martin Owens
-
-This program is free software; you can redistribute it and/or modify
-it under the terms of the GNU General Public License as published by
-the Free Software Foundation; either version 2 of the License, or
-(at your option) any later version.
-
-This program is distributed in the hope that it will be useful,
-but WITHOUT ANY WARRANTY; without even the implied warranty of
-MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
-GNU General Public License for more details.
-
-You should have received a copy of the GNU General Public License
-along with this program; if not, write to the Free Software
-Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
-'''
+#
+# Copyright (C) 2010 Martin Owens
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 2 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program; if not, write to the Free Software
+# Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+#
+"""
+Base module for rendering barcodes for Inkscape.
+"""
import itertools
import sys
from lxml import etree
-class Barcode:
+(WHITE_BAR, BLACK_BAR, TALL_BAR) = range(3)
+TEXT_TEMPLATE = 'font-size:%dpx;text-align:center;text-anchor:middle;'
+
+class Barcode(object):
+ """Provide a base class for all barcode renderers"""
+ name = None
+
+ def error(self, bar, msg):
+ """Cause an error to be reported"""
+ sys.stderr.write(
+ "Error encoding '%s' as %s barcode: %s\n" % (bar, self.name, msg))
+
def __init__(self, param={}):
- self.document = None
- self.x = 0
- self.y = 0
-
- if param.has_key('document'):
- self.document = param['document']
- if param.has_key('x'):
- self.x = param['x']
- if param.has_key('y'):
- self.y = param['y']
-
- if param.has_key('height'):
- self.height = param['height']
- else:
- self.height = 30
-
- self.text = param['text']
- self.label = self.text
- self.string = self.encode( self.text )
+ self.document = param.get('document', None)
+ self.x = int(param.get('x', 0))
+ self.y = int(param.get('y', 0))
+ self.height = param.get('height', 30)
+ self.label = param.get('text', None)
+ self.string = self.encode( self.label )
+
if not self.string:
return
+
self.width = len(self.string)
self.data = self.graphicalArray(self.string)
def generate(self):
+ """Generate the actual svg from the coding"""
svg_uri = u'http://www.w3.org/2000/svg'
if not self.string or not self.data:
return
-
- data = self.data;
-
- # create an SVG document if required
- # if not self.document:
- # self.document = UNKNOWN
-
if not self.document:
- sys.stderr.write("No document defined to add barcode to\n")
- return
+ return self.error("No document defined")
+ data = self.data
# Collect document ids
doc_ids = {}
docIdNodes = self.document.xpath('//@id')
barcode = etree.Element('{%s}%s' % (svg_uri,'g'))
barcode.set('id', name)
barcode.set('style', 'fill: black;')
+ barcode.set('transform', 'translate(%d,%d)' % (self.x, self.y))
- draw = 1
- wOffset = int(self.x)
- id = 1
+ bar_offset = 0
+ bar_id = 1
for datum in data:
# Datum 0 tells us what style of bar is to come next
width = int(datum[1]) * int(style['width'])
if style['write']:
- # Add height for styles such as EA8 where
- # the barcode goes into the text
-
rect = etree.SubElement(barcode,'{%s}%s' % (svg_uri,'rect'))
- rect.set('x', str(wOffset))
+ rect.set('x', str(bar_offset))
rect.set('y', str(style['top']))
rect.set('width', str(width))
rect.set('height', str(style['height']))
- rect.set('id', name + '_bar' + str(id))
- wOffset = int(wOffset) + int(width)
- id = id + 1
+ rect.set('id', "%s_bar%d" % (name, bar_id))
+ bar_offset += width
+ bar_id += 1
- barwidth = wOffset - int(self.x)
+ bar_width = bar_offset
# Add text at the bottom of the barcode
text = etree.SubElement(barcode,'{%s}%s' % (svg_uri,'text'))
- text.set( 'x', str(int(self.x) + int(barwidth / 2)) )
- text.set( 'y', str(int(self.height) + 10 + int(self.y)) )
- text.set( 'style', 'font-size:' + self.fontSize() + 'px;text-align:center;text-anchor:middle;' )
+ text.set( 'x', str(int(bar_width / 2)))
+ text.set( 'y', str(self.height + self.fontSize() ))
+ text.set( 'style', TEXT_TEMPLATE % self.fontSize() )
text.set( '{http://www.w3.org/XML/1998/namespace}space', 'preserve' )
- text.set( 'id', name + '_bottomtext' )
-
+ text.set( 'id', '%s_text' % name )
text.text = str(self.label)
-
return barcode
- # Converts black and white markers into a space array
def graphicalArray(self, code):
+ """Converts black and white markets into a space array"""
return [(x,len(list(y))) for x, y in itertools.groupby(code)]
def getStyle(self, index):
- result = { 'width' : 1, 'top' : int(self.y), 'write' : False }
- if index==1: # Black Bar
+ """Returns the styles that should be applied to each bar"""
+ result = { 'width' : 1, 'top' : 0, 'write' : True }
+ if index == BLACK_BAR:
result['height'] = int(self.height)
- result['write'] = True
+ if index == TALL_BAR:
+ result['height'] = int(self.height) + int(self.fontSize() / 2)
+ if index == WHITE_BAR:
+ result['write'] = False
return result
def fontSize(self):
- return '9'
+ """Return the ideal font size, defaults to 9px"""
+ return 9