README.md

drawSvg

This is a Python 3 library for programmatically generating SVG images (vector drawings) and rendering them or displaying them in an iPython notebook.

Most common SVG tags are supported and others can easily be added by writing a small subclass of DrawableBasicElement or DrawableParentElement.

Install

drawSvg is available on PyPI:

$ pip3 install drawSvg

Examples

Basic drawing elements

import drawSvg as draw

d = draw.Drawing(200, 100, origin='center')

d.append(draw.Lines(-80, -45,
                    70, -49,
                    95, 49,
                    -90, 40,
                    close=False,
            fill='#eeee00',
            stroke='black'))

d.append(draw.Rectangle(0,0,40,50, fill='#1248ff'))
d.append(draw.Circle(-40, -10, 30,
            fill='red', stroke_width=2, stroke='black'))

p = draw.Path(stroke_width=2, stroke='green',
              fill='black', fill_opacity=0.5)
p.M(-30,5)  # Start path at point (-30, 5)
p.l(60,30)  # Draw line to (60, 30)
p.h(-70)    # Draw horizontal line to x=-70
p.Z()       # Draw line to start
d.append(p)

d.append(draw.ArcLine(60,-20,20,60,270,
            stroke='red', stroke_width=5, fill='red', fill_opacity=0.2))
d.append(draw.Arc(60,-20,20,60,270,cw=False,
            stroke='green', stroke_width=3, fill='none'))
d.append(draw.Arc(60,-20,20,270,60,cw=True,
            stroke='blue', stroke_width=1, fill='black', fill_opacity=0.3))

d.setPixelScale(2)  # Set number of pixels per geometry unit
#d.setRenderSize(400,200)  # Alternative to setPixelScale
d.saveSvg('example.svg')
d.savePng('example.png')

# Display in iPython notebook
d.rasterize()  # Display as PNG
d  # Display as SVG

Gradients

import drawSvg as draw

d = draw.Drawing(1.5, 0.8, origin='center')

d.draw(draw.Rectangle(-0.75,-0.5,1.5,1, fill='#ddd'))

# Create gradient
gradient = draw.RadialGradient(0,-0.35,0.7*10)
gradient.addStop(0.5/0.7/10, 'green', 1)
gradient.addStop(1/10, 'red', 0)

# Draw a shape to fill with the gradient
p = draw.Path(fill=gradient, stroke='black', stroke_width=0.002)
p.arc(0,-0.35,0.7,30,120)
p.arc(0,-0.35,0.5,120,30,cw=True, includeL=True)
p.Z()
d.append(p)

# Draw another shape to fill with the same gradient
p = draw.Path(fill=gradient, stroke='red', stroke_width=0.002)
p.arc(0,-0.35,0.75,130,160)
p.arc(0,-0.35,0,160,130,cw=True, includeL=True)
p.Z()
d.append(p)

# Another gradient
gradient2 = draw.LinearGradient(0.1,-0.35,0.1+0.6,-0.35+0.2)
gradient2.addStop(0, 'green', 1)
gradient2.addStop(1, 'red', 0)
d.append(draw.Rectangle(0.1,-0.35,0.6,0.2,
                        stroke='black', stroke_width=0.002,
                        fill=gradient2))

# Display
d.setRenderSize(w=600)
d

Duplicate geometry and clip paths

import drawSvg as draw

d = draw.Drawing(1.4, 1.4, origin='center')

# Define clip path
clip = draw.ClipPath()
clip.append(draw.Rectangle(-.25,.25-1,1,1))

# Draw a cropped circle
c = draw.Circle(0,0,0.5, stroke_width='0.01', stroke='black',
                         fill_opacity=0.3, clip_path=clip,
                         id='circle')
d.append(c)

# Make a transparent copy, cropped again
g = draw.Group(opacity=0.5, clip_path=clip)
g.append(draw.Use('circle', 0.25,0.1))
d.append(g)

# Display
d.setRenderSize(400)
d.rasterize()

Implementing other SVG tags

import drawSvg as draw

# Subclass DrawingBasicElement if it cannot have child nodes
# Subclass DrawingParentElement otherwise
# Subclass DrawingDef if it must go between <def></def> tags in an SVG
class Hyperlink(draw.DrawingParentElement):
    TAG_NAME = 'a'
    def __init__(self, href, target=None, **kwargs):
        # Other init logic...
        # Keyword arguments to super().__init__() correspond to SVG node
        # arguments: stroke_width=5 -> stroke-width="5"
        super().__init__(href=href, target=target, **kwargs)

d = draw.Drawing(1, 1.2, origin='center')

# Create hyperlink
hlink = Hyperlink('https://www.python.org', target='_blank',
                  transform='skewY(-30)')
# Add child elements
hlink.append(draw.Circle(0,0,0.5, fill='green'))
hlink.append(draw.Text('Hyperlink',0.2, 0,0, center=0.6, fill='white'))

# Draw and display
d.append(hlink)
d.setRenderSize(200)
d