A 2D SVG-rendering of the famous glxgears program

gears-2d.py

import svgwrite
import math

def gear_outline(outer_radius, teeth, tooth_depth):
    r1 = outer_radius - tooth_depth / 2.0
    r2 = outer_radius + tooth_depth / 2.0
    da = 2.0 * math.pi / teeth / 4.0

    polygon = []
    for i in range(teeth):
        angle = i * 2.0 * math.pi / teeth
        polygon.append((r1 * math.cos(angle + 0 * da), r1 * math.sin(angle + 0 * da)))
        polygon.append((r2 * math.cos(angle + 1 * da), r2 * math.sin(angle + 1 * da)))
        polygon.append((r2 * math.cos(angle + 2 * da), r2 * math.sin(angle + 2 * da)))
        polygon.append((r1 * math.cos(angle + 3 * da), r1 * math.sin(angle + 3 * da)))
    return polygon

def gear_inner(radius, teeth):
    r0 = radius
    polygon = []
    for i in range(teeth):
        angle = i * 2.0 * math.pi / teeth
        polygon.append((r0 * math.cos(angle), r0 * math.sin(angle)))
        polygon.append((r0 * math.cos(angle), r0 * math.sin(angle)))
    return polygon

dwg = svgwrite.Drawing('test.svg', profile='tiny')
dwg.viewbox(-7.35, -6.35, 13, 13)

red = dwg.add(dwg.g(id='red', fill='red'))
red.add(dwg.polygon(gear_outline(4.0, 20, 0.7)))
red.add(dwg.polygon(gear_inner(1.0, 20)))
red.translate(-3.0, -2.0)
red.rotate(0)

green = dwg.add(dwg.g(id='green', fill='green'))
green.add(dwg.polygon(gear_outline(2.0, 10, 0.7)))
green.add(dwg.polygon(gear_inner(0.5, 10)))
green.translate(3.1, -2.0)
green.rotate(-9)

blue = dwg.add(dwg.g(id='blue', fill='blue'))
blue.translate(-3.1, 4.2)
blue.add(dwg.polygon(gear_outline(2.0, 10, 0.7)))
blue.add(dwg.polygon(gear_inner(1.3, 10)))
blue.rotate(-25)

dwg.save()