A behavior run by another one had a single flow port at its Start
and at its End, so it could not branch for its caller. And it could
not be used as an event: a call needs a pulse at its flow input,
and the events of a called graph never fire. An input like
"Confirm" (Space or Enter) had to be built again in every graph.
- A declared port of a Start or an End node can be of the kind
Flow. It sits above the values and shares their names, exec stays
reserved. Only these two nodes declare one, a struct does not.
- Run behavior shows a flow port of the Start as a further flow
input. A call arriving through it leaves the Start through the
output of that name and not through exec.
- Run behavior shows a flow port of the End as a further flow
output. The call goes on through the one the End was reached by
last, and then through exec. exec fires always, as before.
- On behavior is a new event node without a flow input. The
behavior it names runs at the node for as long as the behavior
around it runs, with all of its own events and one set of
variables per node.
- Its outputs are those of the End. It fires once the inner pulse
is through, by the output the End was reached by last, exec only
for End.exec. A pulse that never reaches the End is not seen.
- The value ports of the Start are its inputs, read anew for each
inner pulse. The Start itself never fires there.
- It nests to any depth. Under a Run behavior it stays silent. A
behavior hearing itself, however far round, is not started and
the node says "A behavior cannot listen to itself".
- The palette offers every other behavior with an End once more as
"On <name>". A node naming one without End says so.
- An On node removed while the game runs ends its behavior with On
disable and On destroy. The sounds of the entity end only with
the behavior placed on it.
- Renaming and deleting a declared port follows the edges at On
behavior nodes as it does at Run behavior nodes.
- The flow outputs of the Start of a behavior placed on an object
never fire, like its exec.
- The engine prompt of the benchmark names flow ports and On
behavior.
Tests:
- Gate on melektaus-atx right before this commit: 215 files, 3319
tests (3278 + 41), exit 0.
- e2e 19 on melektaus-atx: 39 checks (+4), all pass. e2e
1-6,17-24,26,36,51: 628 checks, all pass.
- 19 unit tests in flow-ports.test.ts, 19 in on-behavior.test.ts
on a real world, the rest in the node catalog.
- Four new e2e checks in module 19: a flow port declared by mouse
at the End, On Confirm in the graph, the call leaving through the
further output while playing, Enter and Space on a real keyboard.
- 19 unit counter-probes all fail their tests. One did not at first
(a removed node kept its instance), a test was added. Two browser
counter-probes fail their checks.
- One screenshot looked at: On Confirm with exec and pressed, the
second flow pin at the calling node.
- The e2e sum of 1680 is counted (1676 + 4), the full suite and
the smokes did not run.
- Not seen in the browser: flow inputs at the Start, nesting, the
ring, values through On behavior, the palette entry. No test
holds that the sounds of the entity go on when a heard behavior
ends.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Key is down says whether a key is held. To act once on a press, a
graph had only the events On key down and On key up. A behavior
that is called by another one and reads its input as data had to
keep the state of the last frame in a variable of its own.
- Key was pressed is true for the one frame in which the key goes
down, the frame On key down fires in. Key was released is the
same for the frame the key comes up.
- Both sit next to Key is down in the palette and have the key as
their only setting.
- NodeContext gains wasKeyPressed and wasKeyReleased. The behavior
context answers them from justPressed and justReleased of the
input, through keyName, so a key saved as "A" meets the key "a".
- No repeat. On key down may fire again while a key stays held, a
held key is pressed once here.
- When the window loses the keyboard, every held key counts as
released in that frame, as On key up has it.
- The engine prompt of the benchmark names the two nodes.
Tests:
- Gate on melektaus-atx right before this commit: 213 files, 3278
tests (3264 + 14), exit 0.
- e2e 18,20,43 on melektaus-atx: 57 checks, all pass.
- Ten unit tests in key-edges.test.ts on a real world, four cases
in the node catalog.
- Eight counter-probes all fail their tests. One did not at first
(the case of the key saved on the node), a test was added.
- No e2e check of its own, the sum stays 1676. The nodes were not
looked at in the browser, neither in the palette nor with a real
keyboard.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The prompt is meant as a benchmark: one agent, one prompt, and the goal
is a finished engine rather than a measure of how far it gets.
- The scope follows the decisions made on 2026-10-01. In: projects,
scenes with a hierarchy, camera, containers with nesting and instance
edits, behaviors, shaders and particle effects as graphs, colliders,
animations, text with custom fonts, textures and sprites, state
machines, variables assets, structs, typed lists, sound, the console
and custom curves.
- Out: accounts, plugins, the performance panel, export and player,
tilemaps, the pixel art and vector art editors, run in editor,
snapshots and hierarchy groups.
- The stack is fixed except for the UI framework, which the agent
picks itself. The interface is DOM, Pixi only draws the views.
- "Done" is checkable: three sample games with smoke tests, numbered
acceptance criteria and an ACCEPTANCE.md the agent has to fill in.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
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