#!/usr/bin/env python
"""\
SVG.py - Construct/display SVG scenes.
The following code is a lightweight wrapper around SVG files. The metaphor
is to construct a scene, add objects to it, and then write it to a file
to display it.
This program uses ImageMagick to display the SVG files. ImageMagick also
does a remarkable job of converting SVG files into other formats.
"""
import os
display_prog = 'display' # Command to execute to display images.
class Scene:
def __init__(self,name="svg",height=400,width=400):
self.name = name
self.items = []
self.height = height
self.width = width
return
def add(self,item): self.items.append(item)
def strarray(self):
var = ["<?xml version=\"1.0\"?>\n",
"<svg height=\"%d\" width=\"%d\" >\n" % (self.height,self.width),
" <g style=\"fill-opacity:1.0; stroke:black;\n",
" stroke-width:1;\">\n"]
for item in self.items: var += item.strarray()
var += [" </g>\n</svg>\n"]
return var
def write_svg(self,filename=None):
if filename:
self.svgname = filename
else:
self.svgname = self.name + ".svg"
file = open(self.svgname,'w')
file.writelines(self.strarray())
file.close()
return
def display(self,prog=display_prog):
os.system("%s %s" % (prog,self.svgname))
return
class Line:
def __init__(self,start,end):
self.start = start #xy tuple
self.end = end #xy tuple
return
def strarray(self):
return [" <line x1=\"%d\" y1=\"%d\" x2=\"%d\" y2=\"%d\" />\n" %\
(self.start[0],self.start[1],self.end[0],self.end[1])]
class Circle:
def __init__(self,center,radius,color):
self.center = center #xy tuple
self.radius = radius #xy tuple
self.color = color #rgb tuple in range(0,256)
return
def strarray(self):
return [" <circle cx=\"%d\" cy=\"%d\" r=\"%d\"\n" %\
(self.center[0],self.center[1],self.radius),
" style=\"fill:%s;\" />\n" % colorstr(self.color)]
class Rectangle:
def __init__(self,origin,height,width,color):
self.origin = origin
self.height = height
self.width = width
self.color = color
return
def strarray(self):
return [" <rect x=\"%d\" y=\"%d\" height=\"%d\"\n" %\
(self.origin[0],self.origin[1],self.height),
" width=\"%d\" style=\"fill:%s;\" />\n" %\
(self.width,colorstr(self.color))]
class Text:
def __init__(self,origin,text,size=24):
self.origin = origin
self.text = text
self.size = size
return
def strarray(self):
return [" <text x=\"%d\" y=\"%d\" font-size=\"%d\">\n" %\
(self.origin[0],self.origin[1],self.size),
" %s\n" % self.text,
" </text>\n"]
def colorstr(rgb): return "#%x%x%x" % (rgb[0]/16,rgb[1]/16,rgb[2]/16)
def test():
scene = Scene('test')
scene.add(Rectangle((100,100),200,200,(0,255,255)))
scene.add(Line((200,200),(200,300)))
scene.add(Line((200,200),(300,200)))
scene.add(Line((200,200),(100,200)))
scene.add(Line((200,200),(200,100)))
scene.add(Circle((200,200),30,(0,0,255)))
scene.add(Circle((200,300),30,(0,255,0)))
scene.add(Circle((300,200),30,(255,0,0)))
scene.add(Circle((100,200),30,(255,255,0)))
scene.add(Circle((200,100),30,(255,0,255)))
scene.add(Text((50,50),"Testing SVG"))
scene.write_svg()
scene.display()
return
if __name__ == '__main__': test()
