WallPlotter library
p5 helper for a Marlin polargraph over Web Serial. Coordinates are mm. Origin is machine home (G92). Y positive is up. Chrome or Edge, page on localhost or HTTPS.
Load from this package:
<script src="../../lib/WallPlotter.js"></script>
Example sketch: examples/zickzack/.
new WallPlotter(options?)
All options are optional.
| Option | Default | What it is |
|---|---|---|
baudRate |
115200 |
Serial baud (must match Marlin) |
stepSize |
10 |
Keyboard jog step, mm |
feedRateTravel |
1500 |
Pen-up speed, mm/min (G-code F) |
feedRateDraw |
300 |
Pen-down speed, mm/min |
penUpGcode |
M280 P0 S90 |
Command to lift pen |
penDownGcode |
M280 P0 S50 |
Command to lower pen |
penUpDelayMs |
150 |
Pause after pen up, ms |
penDownDelayMs |
50 |
Pause after pen down, ms |
machineXMin / machineXMax |
-830 / 830 |
Overlay X extents, mm (idler spacing 1660) |
machineYMin / machineYMax |
-1200 / 800 |
Overlay Y; idlers at Y=800 (80 cm above work centre) |
jogIntervalMs |
150 |
Repeat delay while holding arrows, ms |
maxLogLines |
40 |
Serial lines in the selectable log (bottom-right) |
previewMinDelayMs |
30 |
Floor for preview segment wait, ms |
previewFrameMs |
16 |
Preview animation frame time, ms |
timingMultiplier |
1 |
Scale Test preview waits (2 = twice as slow) |
onLog(line) |
no-op | Extra callback for each log line |
onStatusChange(status) |
no-op | 'connected' or 'disconnected' |
Setup / UI
enableKeyInputs()
Keyboard controls. Call from setup(). No arguments.
| Key | Action |
|---|---|
C |
Connect / disconnect |
T |
Run Test (preview) |
A |
Abort / reset Test to start |
H |
Set home here (G92 X0 Y0) — required before Plot |
0 |
Travel to (0, 0) |
P |
Toggle pen |
← → ↑ ↓ |
Jog one step, pen up |
Shift + arrows |
Jog one step, pen down |
+ / - |
Jog step size 1–100 mm |
enablePlotButtons(options?)
Adds Connect, Plot, Test, and Abort buttons. Expects global plot() and test() in the sketch.
Connect is shown only while disconnected (same as key C). While a path is running, Plot becomes Pause; while paused it becomes Resume. Test becomes Stop during a test. Abort stops and resets the Test preview to the start (key A).
| Option | Default | What it is |
|---|---|---|
parentId |
'wallplotter-controls' |
DOM id for the button row |
connectLabel |
'Connect' |
Connect button text |
plotLabel |
'Plot' |
Plot button text when idle |
pauseLabel |
'Pause' |
Plot button while a path is running |
resumeLabel |
'Resume' |
Plot button while paused |
testLabel |
'Test' |
Test button text |
stopLabel |
'Stop' |
Test button while a test is running |
abortLabel |
'Abort' |
Reset test/plot preview to the start |
showInfos()
Draw HUD, path preview, bounds, and key help. Call every frame from draw(). Also runs held-arrow jogging when keys are enabled.
Speed
setSpeed(travel, draw)
Feed rates in mm/min. Used as G-code F and for Test preview timing. Clamped to 1–10000.
travel(number): pen-up /move()speed. Or{ travel, draw }.draw(number, optional): pen-down /draw()speed. Omit to leave draw rate unchanged.
Practical range about 100–10000. Values above 10000 are clamped. Do not use 0.
wp.setSpeed(6000, 2500);
wp.setSpeed({ travel: 6000, draw: 2500 });
setTimingMultiplier(mult)
Scales Test preview waits only. Plot is paced by Marlin (ok + M400).
mult(number):1= matchsetSpeedestimate,2= twice as slow,0.5= twice as fast. Clamped to ≥0.1.
Path (buffered drawing)
move / draw / wait / speed only queue. Nothing is sent until runPath.
startPath()
Clear the path buffer. Returns this.
move(x, y)
Queue pen-up travel to (x, y) mm. Returns this.
draw(x, y)
Queue pen-down stroke to (x, y) mm. Returns this.
wait(ms)
Queue a pause. ms is milliseconds. On Plot, sends G4 P<ms>. Returns this.
speed(travel, drawRate)
Queue a mid-path speed change (mm/min, clamped 1–10000). Either argument may be omitted. Restored after runPath. Returns this.
runPath(testOnly) / runPath(commands, testOnly?)
Run the path. async.
testOnly(boolean):true= preview only, no serial.false= send G-code. Home must be set for Plot.commands(array, optional): explicit list instead of thestartPath()buffer.
Plot: wait for Marlin ok, then M400 (move finished). Test: animate using distance / setSpeed × timingMultiplier.
wp.startPath();
wp.move(-200, -200);
wp.draw(200, -200);
wp.wait(500);
await wp.runPath(false); // plot
await wp.runPath(true); // test
Sketch: plot() → runPath(false), test() → runPath(true).
estimatePathMs(commands?)
Returns estimated duration in milliseconds for the current path buffer, or for commands if given. Uses setSpeed, queued speed(), wait(), and timingMultiplier. The HUD shows elapsed / est / remain while plotting.
stopPath() / stopPlot()
stopPath() aborts the current runPath after the in-flight command gets its ok (it does not cancel that wait — that was dropping the next ok).
stopPlot() first press is the same as Pause: finish the current stroke, then Resume continues. Second press stops the browser from sending more moves. The in-flight G1 still runs — this firmware does not have EMERGENCY_PARSER, so M410 cannot interrupt motion (and on a polargraph it desyncs belts). Unplug power for a hard stop.
pausePlot() / resumePlot() / abortToStart()
Pause / first Stop wait for the current segment to finish (M400), then lift the pen. Resume continues from there.
Abort (button or A) stops the run and resets the Test preview to the start. Live Plot only stops sending further moves; the machine stays where it is.
Serial / machine
All async. Coordinate moves on Plot require home (H) first.
connect()
Web Serial port picker, enable steppers (M17), pen up, query polargraph area (M665 → machine overlay bounds), M114. Reload/close releases the port (needed on macOS). If only one previously allowed port exists, it is reused.
disconnect()
Close the serial port.
send(line, options?)
Write one G-code line and wait for Marlin ok.
line(string): command without newline, e.g.'M114'.options.allowWithoutHome(boolean): allowG0/G1before home. Defaultfalse.options.waitOk(boolean): wait forok. Defaulttrue.options.timeoutMs(number):oktimeout. Default 15000.M400/G4use a longer timeout based on the move or dwell. After 1s with nook, the log showswaiting for Marlin okand the HUD says Waiting for plotter…. During a plot, a timeout pauses so Resume can continue; S / Stop does the same.
penUp(force?) / penDown(force?)
Send pen G-code and wait the pen delay. By default, no-op if already in that state. Pass true to always send (used by P and on connect) so you can test the configured angles.
moveTo(x, y)
Pen up, travel to (x, y) mm immediately (not queued). Requires home.
drawTo(x, y)
Pen down, draw to (x, y) mm immediately. Requires home.
goToZero()
moveTo(0, 0).
step(dx, dy, draw?)
Relative move in mm.
dx,dy(number): delta mmdraw(boolean, defaultfalse):true→drawTo, elsemoveTo
setHomeHere()
G92 X0 Y0. Sets local x,y to 0 and marks home as set.
Fields (read)
| Field | Meaning |
|---|---|
connected |
Serial open |
homeSet |
Home was set with H / setHomeHere() |
x, y |
Current position, mm |
isPenDown |
Pen state |
isPlotting |
runPath in progress |
isPaused |
runPath is paused |
feedRateTravel / feedRateDraw |
Current speeds, mm/min |
timingMultiplier |
Preview wait scale |
stepSize |
Jog step, mm |