PyTamaro

2026-01-09. Filed in public, twoville.

I recently watched an episode of the Computing Education Things podcast in which host Daniel Prol interviewed professor Matthias Hauswirth about teaching computing through the lens of graphics programming. Hauswirth built the learning platform PyTamaro. I'm afraid I didn't listen for the big ideas because I'm already a member of the choir. Rather I was interested in the graphics. These four images were begging to be recreated in Twoville:

let radius = 5
let eraserWidth = 6
let ferruleWidth = 4
let bodyWidth = 40
let tipWidth = 10
let zigzagWidth = 3
let leadWidth = 3
let tipHeight = leadWidth * 1.0 / tipWidth * radius

// Eraser
polygon
  color = [0.8, 0.5, 0.5]
  vertex.position = [eraserWidth, radius]
  vertex.rposition = [0, -2 * radius]
  quadratic.distance = 3
  vertex.rposition = [-eraserWidth, 0]
  vertex.rposition = [0, 2 * radius]

// Ferrule
polygon
  color = [0.9, ~, ~]
  vertex.position = [eraserWidth + ferruleWidth, radius]
  vertex.rposition = [0, -2 * radius]
  vertex.rposition = [-ferruleWidth, 0]
  vertex.rposition = [0, 2 * radius]

// Body
polygon
  color = [0.9, 0.8, 0.2]
  vertex.position = [eraserWidth + ferruleWidth + bodyWidth, radius]
  vertex.rposition = [0, -2 * radius]
  vertex.rposition = [-bodyWidth, 0]
  vertex.rposition = [0, 2 * radius]

// Tip
polygon
  color = [0.95, 0.9, 0.7]
  vertex.position = [eraserWidth + ferruleWidth + bodyWidth, radius]
  vertex.rposition = [tipWidth, -radius]
  vertex.rposition = [-tipWidth, -radius]
  repeat 3
    vertex.rposition = [-zigzagWidth, radius / 3.0]
  around
    vertex.rposition = [zigzagWidth, radius / 3.0]

// Lead
polygon
  color = :black
  vertex.position = [eraserWidth + ferruleWidth + bodyWidth + tipWidth, 0]
  vertex.rposition = [-leadWidth, -tipHeight]
  vertex.rposition = [0, 2 * tipHeight]

view
  autofit = true
  margin = 1

let radius = 5
let eraserWidth = 6
let ferruleWidth = 4
let bodyWidth = 40
let tipWidth = 10
let zigzagWidth = 3
let leadWidth = 3
let tipHeight = leadWidth * 1.0 / tipWidth * radius

// Lead
polygon
  color = :black
  vertex.position = [eraserWidth + ferruleWidth + bodyWidth + tipWidth, 0]
  vertex.rposition = [-leadWidth, -tipHeight]
  vertex.rposition = [0, 2 * tipHeight]

view
  autofit = true
  margin = 1

Twoville code is not shorter than PyTamaro code. There are a couple of reasons for this. First, Twoville uses a declarative approach in which properties are explicitly named across multiple lines. By design, it doesn't have a compact one-line function for drawing a circle. Second, I expressed these shapes parametrically. For the most part, you can modify the variables at the top and see the whole image adapt. This is especially fun to see on the pencil. Put your cursor on the first vertex of the eraser and then drag the handle.