Generic object physics + grab (game layer)

muse-lantern commented

2026-10-29 14:43:57 +00:00

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Background. godot-xr-tools 4.5.2 is vendored unmodified in addons/godot-xr-tools/ (survey 2026-10-28). DEAD AIR's own grabbable/grab-point/ranged-grab are still stubs; there is no grab test; menu/sandbox interaction is pointer-only.

Order of work.

DAFunctionPickup adapter FIRST: xr-tools pickup reads raw grip / trigger_click; DEAD AIR speaks da_* via RigInput. Dropping pickup in raw would bypass the generic layer, the SteamVR pause rules, and flat/headless testing. Pickup nodes belong under grip nodes, not aim nodes.
Then, on top: wrist pivot (xr-tools uses a palm-centre offset), two-hand midpoint-between-palms (xr-tools blends by vote — different kinematics), ranged tiers (tier 1 can ride the lerp driver; tier 2 ballistic arc is new), grip poses as data tables (issue #4, not editor pose resources), item-type / save bridging including inert-on-addon-removal, and a single documented physics layer map (currently scattered: pickable 3, handle 19, held 17, menu 21).

Use as-is from xr-tools (no rework): pickables, one-hand grab detection, throw (velocity averager, 5 samples x impulse factor), snap zones/holsters, interactables (levers/buttons/hinges/sliders), player-body pushing.

Background. godot-xr-tools 4.5.2 is vendored unmodified in addons/godot-xr-tools/ (survey 2026-10-28). DEAD AIR's own grabbable/grab-point/ranged-grab are still stubs; there is no grab test; menu/sandbox interaction is pointer-only. Order of work. 1. DAFunctionPickup adapter FIRST: xr-tools pickup reads raw grip / trigger_click; DEAD AIR speaks da_* via RigInput. Dropping pickup in raw would bypass the generic layer, the SteamVR pause rules, and flat/headless testing. Pickup nodes belong under grip nodes, not aim nodes. 2. Then, on top: wrist pivot (xr-tools uses a palm-centre offset), two-hand midpoint-between-palms (xr-tools blends by vote — different kinematics), ranged tiers (tier 1 can ride the lerp driver; tier 2 ballistic arc is new), grip poses as data tables (issue #4, not editor pose resources), item-type / save bridging including inert-on-addon-removal, and a single documented physics layer map (currently scattered: pickable 3, handle 19, held 17, menu 21). Use as-is from xr-tools (no rework): pickables, one-hand grab detection, throw (velocity averager, 5 samples x impulse factor), snap zones/holsters, interactables (levers/buttons/hinges/sliders), player-body pushing.

muse-lantern referenced this issue

2026-10-29 14:45:52 +00:00

Module framework: slice 1 follow-ups + open design questions #27

muse-lantern commented

2026-11-02 04:25:31 +00:00

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Update from craftanything (upstream branch, tip c64b8bd). The core of this issue lands in-branch:

Hand interaction driven by RigInput (generic da_* actions), not raw XR input: HandInteractor, Grabbable, GrabPoint, RangedGrab, Snapper, Volume, Inventory, WorldItem.
Grip rules from #15 implemented: one hand pivots at the wrist, two hands at the midpoint between the palms. Throw works off the hand's recent velocity estimate (GameRules throw multiplier).
Grip poses and markers are data: ItemSpec (grip_poses + markers, validated) shared by GenericItem and ItemDefinition.
Physics layers written down as PhysLayers (world 1, entity 2, item 11, trigger 12, player 20); xr-tools' own layers (3/17/19) are left alone.

One divergence to flag: this is a hand-rolled interactor, NOT the DAFunctionPickup adapter to xr-tools that this issue planned. The behaviour is there; the architecture choice needs blessing.

Still open: bridge grab simulation (#26) and headset verification of how it actually feels. Verified on the branch (lantern-vm, Godot 4.6.3): clean double import, full headless suite list PASS. Branch state only — not in main yet.

Update from `craftanything` (upstream branch, tip `c64b8bd`). The core of this issue lands in-branch: - Hand interaction driven by `RigInput` (generic `da_*` actions), not raw XR input: `HandInteractor`, `Grabbable`, `GrabPoint`, `RangedGrab`, `Snapper`, `Volume`, `Inventory`, `WorldItem`. - Grip rules from #15 implemented: one hand pivots at the wrist, two hands at the midpoint between the palms. Throw works off the hand's recent velocity estimate (`GameRules` throw multiplier). - Grip poses and markers are data: `ItemSpec` (`grip_poses` + `markers`, validated) shared by `GenericItem` and `ItemDefinition`. - Physics layers written down as `PhysLayers` (world 1, entity 2, item 11, trigger 12, player 20); xr-tools' own layers (3/17/19) are left alone. One divergence to flag: this is a hand-rolled interactor, NOT the `DAFunctionPickup` adapter to xr-tools that this issue planned. The behaviour is there; the architecture choice needs blessing. Still open: bridge grab simulation (#26) and headset verification of how it actually feels. Verified on the branch (lantern-vm, Godot 4.6.3): clean double import, full headless suite list PASS. Branch state only — not in main yet.

muse-lantern referenced this issue

2026-11-02 04:35:08 +00:00

Tracking: craftanything branch — modularization completion #29

muse-lantern commented

2026-11-13 02:51:26 +00:00

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Closing: the core of this issue is on main via the craftanything merge (PR #30, 94bb04078) and the work since — HandInteractor, Grabbable, GrabPoint, RangedGrab, Snapper, Volume, Inventory, WorldItem, grip poses + markers as data (ItemSpec), and PhysLayers — as recorded in comment 837. Divergences from the plan, for the record:

The DAFunctionPickup adapter to xr-tools was not built; the interactor is hand-rolled instead. That architecture choice is ratified in practice by every merge since that builds on it (sandbox, containers, editor, the #43 hand spike).
The two-hand midpoint rule was superseded by #33's pivot revision: the primary grip is master, the secondary hand steers pitch/yaw only.
The tier-2 ballistic-arc ranged grab was not built. If it is still wanted, it needs a new issue.
Bridge grab simulation stays open separately as #26; headset feel verification is ongoing work, not this issue's scope.

— Lantern, closing on merith's go-ahead to close tracking issues already merged via another means.

Closing: the core of this issue is on main via the craftanything merge (PR #30, `94bb04078`) and the work since — `HandInteractor`, `Grabbable`, `GrabPoint`, `RangedGrab`, `Snapper`, `Volume`, `Inventory`, `WorldItem`, grip poses + markers as data (`ItemSpec`), and `PhysLayers` — as recorded in comment 837. Divergences from the plan, for the record: - The `DAFunctionPickup` adapter to xr-tools was not built; the interactor is hand-rolled instead. That architecture choice is ratified in practice by every merge since that builds on it (sandbox, containers, editor, the #43 hand spike). - The two-hand midpoint rule was superseded by #33's pivot revision: the primary grip is master, the secondary hand steers pitch/yaw only. - The tier-2 ballistic-arc ranged grab was not built. If it is still wanted, it needs a new issue. - Bridge grab simulation stays open separately as #26; headset feel verification is ongoing work, not this issue's scope. — Lantern, closing on merith's go-ahead to close tracking issues already merged via another means.

muse-lantern closed this issue

2026-11-13 02:51:27 +00:00

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Generic object physics + grab (game layer) #25