def save_radial_tree_plot(filename, root_list, step_size):
# define some params
white = "rgb(255, 255, 255)"
black = "rgb(0, 0, 0)"
# create the drawing surface
svg_drawing = Drawing(
filename=filename,
size=(SVG_SIZE, SVG_SIZE),
debug=True)
# create defs, in this case, just a single gradient
rad_grad = svg_drawing.radialGradient(("50%", "50%"), "100%", ("50%", "50%"), id="rad_grad")
rad_grad.add_stop_color("0%", black, 255)
rad_grad.add_stop_color("100%", white, 255)
svg_drawing.defs.add(rad_grad)
tree_plot = svg_drawing.mask(
id='treeplot',
style='stroke: black; stroke-width: 3; fill: none; stroke-linecap: round; stroke-opacity: 0.5;')
tree_plot.add(svg_drawing.rect( (0, 0), (SVG_SIZE, SVG_SIZE) ).fill(white))
for root in root_list:
draw_radial_tree_node(svg_drawing, tree_plot, root, rad_grad, step_size)
base_rect = svg_drawing.rect( (0, 0), (SVG_SIZE, SVG_SIZE), mask="url(#treeplot)").fill(black)
svg_drawing.add(base_rect)
svg_drawing.add(tree_plot)
svg_drawing.save()
