from Hacker News

Flag drawing with Turtle

by grokx on 1/20/25, 8:51 PM with 6 comments

• by harywilke on 1/21/25, 10:06 AM

  Two fun flag facts. The red dot on the flag of Japan was off center by 1/100 towards the pole before 1999. The naval flag of France is not of equal proportions. the proportion are; blue 30, white 33, and red 37

• by jll29 on 1/21/25, 6:45 AM

  Yes turtle graphics are very educational, I taught it (via PyTurtle) to 11-year-olds, who picked it up easily ("draw a house, then translate into instructions for the little turtle").

  BTW, there is no "Western European Union" any more, just one European Union, so the now simplified flag can leave out the white ugly letters in the middle.

• by lores on 1/21/25, 1:52 PM

  I'm in awe that in 2024 the first introduction to programming can be a turtle in Python, just like it was in 1982 when someone came to my primary school to show everyone a turtle in Logo.

• by userbinator on 1/21/25, 2:50 AM

  Filling on self-intersection is probably broken

  That's always an edge-case (literally); having written various vector graphics converters over the years, the fundamentals are usually straightforward (although in this case converting between Cartesian absolute and polar relative coordinates can also introduce numerical precision issues), but depending on things like fill rule compatibility, these tricky cases tend to result in a lot of code dedicated to handling them correctly.

  Even different OS' graphics stacks disagree: https://bugs.python.org/issue39392

  Unfortunately there's a lack of US flag in the examples, but the Wales one makes up for it in complexity.

• by jony1266 on 1/21/25, 5:09 AM

  this is unbelievably cool... I remember turtle was the first thing I learned when learning python and it was super hard to make stuff that looked genuinely good. writing a tool to parse svgs into turtle code is a great strat

• by rossant on 1/21/25, 7:44 AM

  (2018)