A Python 3 library for programmatically generating SVG images and animations that can render and display your drawings in a Jupyter notebook or Jupyter lab.
Most common SVG tags are supported and others can easily be added by writing a small subclass of DrawableBasicElement or DrawableParentElement. Nearly all SVG attributes are supported via keyword args (e.g. Python keyword argument fill_opacity=0.5 becomes SVG attribute fill-opacity="0.5").
An interactive Jupyter notebook widget, drawsvg.widgets.DrawingWidget, is included that can update drawings based on mouse events. The widget does not yet work in Jupyter lab.
Install#
drawsvg is available on PyPI: Install the pre-release of drawsvg 2.0:
$ python3 -m pip install -e "git+https://github.com/cduck/drawsvg.git@v2#egg=drawsvg[all]"
$ pip3 install "drawsvg[all]"
Prerequisites (optional)#
Cairo needs to be installed separately. When Cairo is installed, drawsvg can output PNG or other image formats in addition to SVG. See platform-specific instructions for Linux, Windows, and macOS from Cairo. Below are some examples for installing Cairo on Linux distributions and macOS.
Ubuntu
$ sudo apt-get install libcairo2
macOS
Using homebrew:
$ brew install cairo
Examples#
Basic drawing elements#
import drawsvg as draw
d = draw.Drawing(200, 100, origin='center')
# Draw an irregular polygon
d.append(draw.Lines(-80, 45,
70, 49,
95, -49,
-90, -40,
close=False,
fill='#eeee00',
stroke='black'))
# Draw a rectangle
r = draw.Rectangle(-80, -50, 40, 50, fill='#1248ff')
r.append_title("Our first rectangle") # Add a tooltip
d.append(r)
# Draw a circle
d.append(draw.Circle(-40, 10, 30,
fill='red', stroke_width=2, stroke='black'))
# Draw an arbitrary path (a triangle in this case)
p = draw.Path(stroke_width=2, stroke='lime', fill='black', fill_opacity=0.2)
p.M(-10, -20) # Start path at point (-10, -20)
p.C(30, 10, 30, -50, 70, -20) # Draw a curve to (70, -20)
d.append(p)
# Draw text
d.append(draw.Text('Basic text', 8, -10, -35, fill='blue')) # 8pt text at (-10, -35)
d.append(draw.Text('Path text', 8, path=p, text_anchor='start', line_height=1))
d.append(draw.Text(['Multi-line', 'text'], 8, path=p, text_anchor='end', center=True))
# Draw multiple circular arcs
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, 90, -60, cw=True,
stroke='green', stroke_width=3, fill='none'))
d.append(draw.Arc(60, 20, 20, -60, 90, cw=False,
stroke='blue', stroke_width=1, fill='black', fill_opacity=0.3))
# Draw arrows
arrow = draw.Marker(-0.1, -0.51, 0.9, 0.5, scale=4, orient='auto')
arrow.append(draw.Lines(-0.1, 0.5, -0.1, -0.5, 0.9, 0, fill='red', close=True))
p = draw.Path(stroke='red', stroke_width=2, fill='none',
marker_end=arrow) # Add an arrow to the end of a path
p.M(20, 40).L(20, 27).L(0, 20) # Chain multiple path commands
d.append(p)
d.append(draw.Line(30, 20, 0, 10,
stroke='red', stroke_width=2, fill='none',
marker_end=arrow)) # Add an arrow to the end of a line
d.set_pixel_scale(2) # Set number of pixels per geometry unit
#d.set_render_size(400, 200) # Alternative to set_pixel_scale
d.save_svg('example.svg')
d.save_png('example.png')
# Display in Jupyter notebook
d.rasterize() # Display as PNG
d # Display as SVG
SVG-native animation with playback controls#
import drawsvg as draw
d = draw.Drawing(400, 200, origin='center',
animation_config=draw.types.SyncedAnimationConfig(
# Animation configuration
duration=8, # Seconds
show_playback_progress=True,
show_playback_controls=True,
)
)
d.append(draw.Rectangle(-200, -100, 400, 200, fill='#eee')) # Background
d.append(draw.Circle(0, 0, 40, fill='green')) # Center circle
circle = draw.Circle(0, 0, 0, fill='silver', stroke='gray') # Moving circle
# Animation
circle.add_key_frame(0, cx=-100, cy=0, r=0, stroke_width=0)
circle.add_key_frame(2, cx=0, cy=-100, r=40, stroke_width=5)
circle.add_key_frame(4, cx=100, cy=0, r=0, stroke_width=0)
circle.add_key_frame(6, cx=0, cy=100, r=40, stroke_width=5)
circle.add_key_frame(8, cx=-100, cy=0, r=0, stroke_width=0)
d.append(circle)
# Changing text
draw.native_animation.animate_text_sequence(
d,
[0, 2, 4, 6],
['0', '1', '2', '3'],
30, 0, 1, fill='yellow', center=True)
# Save as a standalone animated SVG or HTML
d.save_svg('playback-controls.svg')
d.save_html('playback-controls.html')
# Display in Jupyter notebook
#d.display_image() # Display SVG as an image (will not be interactive)
#d.display_iframe() # Display as interactive SVG (alternative)
d.display_inline() # Display as interactive SVG
Note: GitHub blocks the playback controls. Download the above SVG and open it in a web browser to try.
Patterns and gradients#
import drawsvg as draw
d = draw.Drawing(1.5, 0.8, origin='center')
# Background pattern (not supported by Cairo, rasterize will not show it)
pattern = draw.Pattern(width=0.13, height=0.23)
pattern.append(draw.Rectangle(0, 0, .1, .1, fill='yellow'))
pattern.append(draw.Rectangle(0, .1, .1, .1, fill='orange'))
d.draw(draw.Rectangle(-0.75, -0.5, 1.5, 1, fill=pattern, fill_opacity=0.4))
# Create gradient
gradient = draw.RadialGradient(0, 0.35, 0.7*10)
gradient.add_stop(0.5/0.7/10, 'green', 1)
gradient.add_stop(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, cw=False)
p.arc(0, 0.35, 0.5, -120, -30, cw=True, include_l=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, cw=False)
p.arc(0, 0.35, 0, -160, -130, cw=True, include_l=True)
p.Z()
d.append(p)
# Another gradient
gradient2 = draw.LinearGradient(0.1, 0.35, 0.1+0.6, 0.35+0.2)
gradient2.add_stop(0, 'green', 1)
gradient2.add_stop(1, 'red', 0)
d.append(draw.Rectangle(0.1, 0.15, 0.6, 0.2,
stroke='black', stroke_width=0.002,
fill=gradient2))
# Display
d.set_render_size(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))
# Draw a cropped circle
circle = draw.Circle(0, 0, 0.5,
stroke_width='0.01', stroke='black',
fill_opacity=0.3, clip_path=clip)
d.append(circle)
# Make a transparent copy, cropped again
g = draw.Group(opacity=0.5, clip_path=clip)
# Here, circle is not directly appended to the drawing.
# drawsvg recognizes that `Use` references `circle` and automatically adds
# `circle` to the <defs></defs> section of the SVG.
g.append(draw.Use(circle, 0.25, -0.1))
d.append(g)
# Display
d.set_render_size(400)
d.rasterize()
Organizing and duplicating drawing elements#
import drawsvg as draw
d = draw.Drawing(300, 100)
d.set_pixel_scale(2)
# Use groups to contain other elements
# Children elements of groups inherit the coordinate system (transform)
# and attribute values
group = draw.Group(fill='orange', transform='rotate(-20)')
group.append(draw.Rectangle(0, 10, 20, 40)) # This rectangle will be orange
group.append(draw.Circle(30, 40, 10)) # This circle will also be orange
group.append(draw.Circle(50, 40, 10, fill='green')) # This circle will not
d.append(group)
# Use the Use element to make duplicates of elements
# Each duplicate can be placed at an offset (x, y) location and any additional
# attributes (like fill color) are inherited if the element didn't specify them.
d.append(draw.Use(group, 80, 0, stroke='black', stroke_width=1))
d.append(draw.Use(group, 80, 20, stroke='blue', stroke_width=2))
d.append(draw.Use(group, 80, 40, stroke='red', stroke_width=3))
d.display_inline()
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 -> <a stroke-width="5" ...>...</a>
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.set_render_size(200)
d
Animation with the SVG Animate Tag#
import drawsvg as draw
d = draw.Drawing(200, 200, origin='center')
# Animate the position and color of circle
c = draw.Circle(0, 0, 20, fill='red')
# See for supported attributes:
# https://developer.mozilla.org/en-US/docs/Web/SVG/Element/animate
c.append_anim(draw.Animate('cy', '6s', '-80;80;-80',
repeatCount='indefinite'))
c.append_anim(draw.Animate('cx', '6s', '0;80;0;-80;0',
repeatCount='indefinite'))
c.append_anim(draw.Animate('fill', '6s', 'red;green;blue;yellow',
calc_mode='discrete',
repeatCount='indefinite'))
d.append(c)
# Animate a black circle around an ellipse
ellipse = draw.Path()
ellipse.M(-90, 0)
ellipse.A(90, 40, 360, True, True, 90, 0) # Ellipse path
ellipse.A(90, 40, 360, True, True, -90, 0)
ellipse.Z()
c2 = draw.Circle(0, 0, 10)
# See for supported attributes:
# https://developer.mozilla.org/en-US/docs/Web/SVG/Element/animate_motion
c2.append_anim(draw.AnimateMotion(ellipse, '3s',
repeatCount='indefinite'))
# See for supported attributes:
# https://developer.mozilla.org/en-US/docs/Web/SVG/Element/animate_transform
c2.append_anim(draw.AnimateTransform('scale', '3s', '1,2;2,1;1,2;2,1;1,2',
repeatCount='indefinite'))
d.append(c2)
d.save_svg('animated.svg') # Save to file
d # Display in Jupyter notebook
Interactive Widget#
import drawsvg as draw
from drawsvg.widgets import DrawingWidget
import hyperbolic.poincare.shapes as hyper # pip3 install hyperbolic
from hyperbolic import euclid
# Patch the hyperbolic package for drawsvg version 2
patch = lambda m: lambda self, **kw: m(self, draw, **kw)
hyper.Circle.to_drawables = patch(hyper.Circle.toDrawables)
hyper.Line.to_drawables = patch(hyper.Line.toDrawables)
euclid.Arc.Arc.drawToPath = lambda self, path, includeM=True, includeL=False: path.arc(self.cx, self.cy, self.r, self.startDeg, self.endDeg, cw=not self.cw, include_m=includeM, include_l=includeL)
# Create drawing
d = draw.Drawing(2, 2, origin='center', context=draw.Context(invert_y=True))
d.set_render_size(500)
d.append(draw.Circle(0, 0, 1, fill='orange'))
group = draw.Group()
d.append(group)
# Update the drawing based on user input
click_list = []
def redraw(points):
group.children.clear()
for x1, y1 in points:
for x2, y2 in points:
if (x1, y1) == (x2, y2): continue
p1 = hyper.Point.fromEuclid(x1, y1)
p2 = hyper.Point.fromEuclid(x2, y2)
if p1.distanceTo(p2) <= 2:
line = hyper.Line.fromPoints(*p1, *p2, segment=True)
group.draw(line, hwidth=0.2, fill='white')
for x, y in points:
p = hyper.Point.fromEuclid(x, y)
group.draw(hyper.Circle.fromCenterRadius(p, 0.1),
fill='green')
redraw(click_list)
# Create interactive widget and register mouse events
widget = DrawingWidget(d)
@widget.mousedown
def mousedown(widget, x, y, info):
if (x**2 + y**2) ** 0.5 + 1e-5 < 1:
click_list.append((x, y))
redraw(click_list)
widget.refresh()
@widget.mousemove
def mousemove(widget, x, y, info):
if (x**2 + y**2) ** 0.5 + 1e-5 < 1:
redraw(click_list + [(x, y)])
widget.refresh()
widget
Note: The above example currently only works in jupyter notebook, not jupyter lab.
Frame-by-Frame Animation#
import drawsvg as draw
# Draw a frame of the animation
def draw_frame(t):
d = draw.Drawing(2, 6.05, origin=(-1, -5))
d.set_render_size(h=300)
d.append(draw.Rectangle(-2, -6, 4, 8, fill='white'))
d.append(draw.Rectangle(-1, 1, 2, 0.05, fill='brown'))
t = (t + 1) % 2 - 1
y = t**2 * 4 - 4
d.append(draw.Circle(0, y, 1, fill='lime'))
return d
with draw.frame_animate_jupyter(draw_frame, delay=0.05) as anim:
# Or:
#with draw.animate_video('example6.gif', draw_frame, duration=0.05
# ) as anim:
# Add each frame to the animation
for i in range(20):
anim.draw_frame(i/10)
for i in range(20):
anim.draw_frame(i/10)
for i in range(20):
anim.draw_frame(i/10)
Asynchronous Frame-based Animation in Jupyter#
# Jupyter cell 1:
import drawsvg as draw
from drawsvg.widgets import AsyncAnimation
widget = AsyncAnimation(fps=10)
widget
# [Animation is displayed here (click to pause)]
# Jupyter cell 2:
global_variable = 'a'
@widget.set_draw_frame # Animation above is automatically updated
def draw_frame(secs=0):
# Draw something...
d = draw.Drawing(100, 40)
d.append(draw.Text(global_variable, 20, 0, 30))
d.append(draw.Text('{:0.1f}'.format(secs), 20, 30, 30))
return d
# Jupyter cell 3:
global_variable = 'b' # Animation above now displays 'b'
Note: The above example currently only works in jupyter notebook, not jupyter lab.