Axxy v1

Move forward by distance pixels in the current heading. Draws a line if pen is down. Negative distance moves backward.

forward 100
forward $step
forward -30   comment same as backward 30

Move in the opposite direction to the current heading. Equivalent to forward -distance.

Rotate by angle degrees without drawing. right turns clockwise (increases heading); left turns counter-clockwise.

Jump to canvas coordinates. If the pen is down a straight line is drawn to the destination. Use penup first to teleport silently. Does not change the heading.

penup
goto 100 400
pendown

Change only one axis of the position, leaving the other unchanged.

Set the heading to an absolute angle in degrees. Useful for resetting direction precisely without accumulated rounding errors.

setheading 0    comment face right
setheading 270  comment face up
setheading $angle

Jump to the canvas centre (canvasW/2, canvasH/2) and reset heading to 0. Pen state is unchanged — if the pen is down a line is drawn back to the centre.

Draw a curved arc. The axolotl moves along an arc of the given radius, turning through sweep degrees. arcright curves clockwise; arcleft curves counter-clockwise. The heading changes by sweep degrees at the end.

comment Full circle using four quarter-arcs
repeat 4 { arcright 50 90 }

comment Petal shape: two facing arcs
arcright 50 80
right    100
arcright 50 80
right    180

Lift or lower the pen. With pen up, movement does not draw. pentoggle up and pentoggle down are also valid.

Set the stroke colour. Accepts a hex code or three separate R G B values (0–255). Also accepts CSS colour names.

setcolor #e8456a
setcolor 232 69 106  comment same as above
setcolor $inkColor
randomcolor          comment random colour

Set the fill colour for beginfill / endfill. Same colour format as setcolor.

Set the line thickness in pixels. Default is 2. Setting weight to 0 disables line drawing entirely (movement still happens).

Set opacity. 100 is fully opaque; 0 is invisible. Applies to both lines and fills. Useful for layering translucent shapes.

beginfill starts recording path vertices. Every move command adds vertices. endfill closes the shape and renders it filled with the current fill colour. The stroke is also drawn if weight > 0.

setcolor     #1d4ed8
setfillcolor #60a5fa
beginfill
repeat 6 {
  forward 70
  right   60
}
endfill

Stamp the current stamp image at the axolotl's position, rotated to match the heading. The stamp is coloured with the current pen colour. Configure with setstamp or usesprite.

Configure the stamp. mode is one of: turtleSprite (the axolotl image), uploadedSprite (the currently uploaded sprite file), shape (a built-in shape). When mode is shape, available shapes are: triangle, square, circle, diamond, star.

setstamp shape        star     28
setstamp shape        circle   20
setstamp turtleSprite triangle 32  comment axolotl image

Erase everything on the drawing layer. Position, heading, and pen settings are unchanged.

Change the canvas background colour and clear the drawing layer. Accepts hex or RGB values like setcolor.

Show or hide the axolotl cursor sprite. Hiding is useful for clean geometric art. Aliases: showturtle / hideturtle.

Run the body exactly times iterations. Inside the body, $count is the 1-based iteration number and $index is 0-based.

repeat 36 {
  forward 80
  right   10
}

Loop with a named counter from start to end (inclusive), incrementing by step each iteration. The counter is readable as $varName inside the body. If step is 0, the engine automatically uses 1 when start ≤ end, or -1 when start > end.

comment Growing arc spiral
for r 5 120 6 {
  arcright $r 50
}

comment Count down
for i 10 1 -1 {
  forward $i
  right   36
}

Loop while the condition is true. Condition is checked before each iteration. If false on the first check the body never runs.

var d 200
while $d > 10 {
  repeat 4 { forward $d  right 90 }
  right   13
  mathset d $d * 0.85
}

Loop until the condition becomes true. The body runs at least once; condition is checked after each iteration.

Loop continuously. Include a wait or a tick yield to avoid locking the engine. Use break to exit, or click the Stop button. Safety stop fires after 10,000 iterations without a wait tick.

forever {
  right   3
  forward 4
  wait    16
}

Pause execution for the specified milliseconds. 1000 ms = 1 second. Also yields a frame, allowing the canvas to update and the safety stop to reset.

Pause execution until the condition becomes true. The engine polls up to 20,000 times before throwing a safety error. Useful for waiting on a variable set by an event handler.

Exit the innermost loop immediately. Execution resumes after the loop's closing }.

Exit the current procedure immediately. Has no effect at the top level.

Run the body only when the condition is true.

if $x > 400 { right 90 }

comment compound: and / or
if $count == 6 and $y < 300 { randomcolor }
if $n < 0 or $n > 100    { break }

comment negation
if not $score == 0 { forward 20 }

Run the first body if the condition is true, otherwise run the else body.

ifelse $heading > 180 {
  setcolor #3b82f6
} else {
  setcolor #ef4444
}

Runs once when the program starts, before the main body. Use for setup: set background, draw title text, initialise variables.

Fires when the named key is pressed. Common names: space, up, down, left, right, a–z, 0–9, enter, escape. Inside the handler, $keychar holds the key character and $keycode holds the key code.

on key up    { forward  10 }
on key down  { backward 10 }
on key left  { left     15 }
on key right { right    15 }
on key r     { randomcolor }
on key c     { cleardrawing }

Fires when the canvas is clicked. $eventx and $eventy hold the click coordinates.

on click {
  penup
  goto    $eventx $eventy
  pendown
  stamp
}

Fires when a matching broadcast is sent. Multiple handlers can listen for the same message.

Send a broadcast message from anywhere in the program to trigger matching on broadcast handlers.

Fires every animation frame (~60 fps). Requires Instant mode to be enabled. Designed for real-time animation. The body runs synchronously so keep it fast — avoid wait inside. Stop with stopdraw.

comment Spinning arm animation — enable Instant mode first
var a 0

on draw {
  cleardrawing
  setbgcolor  #0f172a
  home
  setcolor    #f472b6
  setweight   3
  setheading  $a
  forward     110
  stamp
  changevar   a 2
}
on key space { stopdraw }

Stop the on draw frame loop. The canvas keeps its current state.

Declare an empty array. Both forms are equivalent.

Append value to the end of the array.

Overwrite the item at zero-based index.

Read the item at index into targetVar. If the index is out of range the target receives 0.

Remove the last item from the array and store it in targetVar. If the array is empty, target receives 0.

Store the current length of the array in targetVar. Use this before a while loop to iterate over all items.

array     angles
arraypush angles 30
arraypush angles 90
arraypush angles 120
arraypush angles 60

arraylen  angles n
var       i 0
while $i < $n {
  arrayget  angles $i turn
  forward   80
  right     $turn
  changevar i 1
}

Create a new axolotl at the canvas centre with default settings (pen down, colour #235390, weight 2). It immediately becomes the active axolotl.

Switch which axolotl is active. All subsequent motion and pen commands apply to it. useaxolotl main returns to the original.

Copy the active axolotl — including its position, heading, and all pen settings — into a new named axolotl. The clone becomes active immediately.

Remove a named axolotl from the scene. main cannot be removed. The active axolotl does not change automatically — call useaxolotl main if needed.

newaxolotl    a
newaxolotl    b

useaxolotl    a
setcolor      #f95858
penup  goto 180 250  pendown
repeat 36 { forward 80  right 170 }

useaxolotl    b
setcolor      #38a8ff
penup  goto 420 250  pendown
repeat 36 { forward 80  right 170 }

useaxolotl main

Switch the stamp to a named sprite variable at the given size (pixels). After calling this, stamp will draw that image. The sprite is scaled to fit within a size × size bounding box.

Stamp the named sprite at the current position without permanently switching the active stamp mode. The previous stamp configuration is preserved.

comment Requires sprite variable 'gem' in the Variables panel
usesprite gem 48
penup
repeat 12 {
  forward  110
  stamp
  backward 110
  right    30
}