The turtle
Each window has a turtle: a pen that starts in the middle of the window, facing up. It draws as it walks.
repeat 4 [ forward 100 right 90]
forward and back walk, left and right turn by degrees (right turns clockwise), and home goes back to the middle, facing up, without drawing. pen up stops it drawing and pen down starts again:
repeat 12 [ forward 20 pen up forward 20 pen down]
The turtle draws its lines in the stroke color and thickness, so set them first. With the stroke off, as in a new sketch, it draws in black.
stroke tomatothickness 4repeat 5 [ forward 150 right 144]
The turtle in draw
Like the style, the turtle starts again at home every frame, and push [ ] puts it back where it was afterwards. Together with a verb that uses itself, that draws trees:
learn branch size [ if size < 8 [ stop ] thickness (size / 10) forward size push [ left 20 branch (size * 0.7) ] push [ right 30 branch (size * 0.7) ]]draw [ background 240 stroke (rgb 70 50 40) pen up back 140 pen down branch 80]
Logo’s short words (fd, rt, pu) are not words of rocinante, but writing one gets you a message naming the whole word.