Ride the zip line and play on the playground

sermuns commented

2026-10-19 21:41:40 +00:00

Owner

The campus has 28 playgrounds, and the extract even names the furniture:

 28  leisure=playground      (one named Lill-Valla)
  1  playground=zipwire
  1  playground=seesaw
  2  playground=structure
 13  leisure=picnic_table

#33 bakes the playgrounds and their furniture. This is the follow-up that makes
them playable.

Zip line: grab the handle, slide down the cable, drop at the end. A spline
between the two posts and a pose is enough; gravity does the rest.
Seesaw: two players, a balance that tips with weight and push. The first
genuinely multiplayer playground toy.
Swing and slide: a pendulum and a short slide, both with a sit pose.

None of this needs scoring. It is the one part of campus that is explicitly for
playing, and the zip line is the only one of its kind in the extract, which makes
it worth finding.

Related

#33 the bake this follows
#44 the other physics toy on campus
#11 the projectile code if the zip line wants a release arc
#68 the sit pose it shares

The campus has 28 playgrounds, and the extract even names the furniture: ``` 28 leisure=playground (one named Lill-Valla) 1 playground=zipwire 1 playground=seesaw 2 playground=structure 13 leisure=picnic_table ``` #33 bakes the playgrounds and their furniture. This is the follow-up that makes them playable. - **Zip line**: grab the handle, slide down the cable, drop at the end. A spline between the two posts and a pose is enough; gravity does the rest. - **Seesaw**: two players, a balance that tips with weight and push. The first genuinely multiplayer playground toy. - **Swing and slide**: a pendulum and a short slide, both with a sit pose. None of this needs scoring. It is the one part of campus that is explicitly for playing, and the zip line is the only one of its kind in the extract, which makes it worth finding. --- **Related** - #33 the bake this follows - #44 the other physics toy on campus - #11 the projectile code if the zip line wants a release arc - #68 the sit pose it shares

sermuns added the

feature request

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labels

2026-10-19 22:13:45 +00:00

sermuns added this to the Play milestone

2026-10-19 22:18:55 +00:00

sermuns commented

2026-10-19 22:46:21 +00:00

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Owner

The zip line is a good one-off and fits the existing prop/pose work. The seesaw, swing and slide turn this into three minigames: a multiplayer weight-balance toy, a pendulum, and another sit/exit interaction. That is more than "the follow-up that makes playgrounds playable". I'd scope this to the zip line (plus the sit pose from #68) and leave the rest until the playground props are actually in the world and fun to walk through. The zip line is one asset; don't spend the whole issue on the theme park.

sermuns commented

2026-10-20 07:53:37 +00:00

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Owner

Context update: #33 is merged (668cd75 + rebake 20e58ed), so all 28 playgrounds and their swings, slide, seesaw and climbing frame are in the world. The playground=zipwire node is still not baked — only leisure=playground, playground=seesaw and playground=structure are mapped — so the zip line is the concrete next step. The seesaw/swing/slide part now has geometry to attach to.

Context update: #33 is merged (`668cd75` + rebake `20e58ed`), so all 28 playgrounds and their swings, slide, seesaw and climbing frame are in the world. The `playground=zipwire` node is still not baked — only `leisure=playground`, `playground=seesaw` and `playground=structure` are mapped — so the zip line is the concrete next step. The seesaw/swing/slide part now has geometry to attach to.

sermuns referenced this issue

2026-10-20 23:41:20 +00:00

Make the playground toys real mechanisms #113

sermuns commented

2026-10-20 23:42:27 +00:00

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Owner

Every mechanism in this issue has a joint, which makes this the place where a
physics engine stops being optional.

#113 takes the three toys and gives them their real mechanisms:

Zip line: a rope joint between the two posts is the cable — a maximum
distance the handle cannot exceed — and the handle slides down it under
gravity. The "spline between the two posts and a pose is enough" above
becomes a constraint, and the cable cannot stretch.
Seesaw: a revolute joint with an angular limit. Weight on one end tips
it, so the "balance that tips with weight and push" stops being a rule and
becomes the plank's actual angle. Two players on either end is the first
genuinely multiplayer playground toy in the campus.
Swing and slide: a pendulum is a revolute joint with a limit, and a
slide is a low-friction ramp.

The hard part is the player on the toy, and it is worth being honest about
it. A player standing on a moving platform is a kinematic body moving under a
dynamic one, but a player riding a seesaw is not standing on it — the plank
has to carry them, which means the player becomes a physics body while
mounted. That is #114's ragdoll work, and it is the reason to do the ragdoll
before the toys.

The swing is the easy case and worth doing first: the seat hangs from the
joint and the seat carries the player, because it is the same rigid body.

Related: #110 the physics engine, #113 the mechanisms, #114 the ragdoll.

Every mechanism in this issue has a joint, which makes this the place where a physics engine stops being optional. #113 takes the three toys and gives them their real mechanisms: - **Zip line**: a rope joint between the two posts *is* the cable — a maximum distance the handle cannot exceed — and the handle slides down it under gravity. The "spline between the two posts and a pose is enough" above becomes a constraint, and the cable cannot stretch. - **Seesaw**: a revolute joint with an angular limit. Weight on one end tips it, so the "balance that tips with weight and push" stops being a rule and becomes the plank's actual angle. Two players on either end is the first genuinely multiplayer playground toy in the campus. - **Swing and slide**: a pendulum is a revolute joint with a limit, and a slide is a low-friction ramp. The hard part is the player on the toy, and it is worth being honest about it. A player standing on a moving platform is a kinematic body moving under a dynamic one, but a player *riding* a seesaw is not standing on it — the plank has to carry them, which means the player becomes a physics body while mounted. That is #114's ragdoll work, and it is the reason to do the ragdoll before the toys. The swing is the easy case and worth doing first: the seat hangs from the joint and the seat carries the player, because it is the same rigid body. Related: #110 the physics engine, #113 the mechanisms, #114 the ragdoll.

sermuns commented

2026-10-22 12:27:10 +00:00

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Owner

The zip wire is in the world. Riding it is not.

playground=zipwire now bakes as PROP_ZIPWIRE with a model (dafe0e3), so the cable's two posts stand on the campus and the one-of-its-kind node is worth looking for. The seesaw, the climbing frame, the slide and the swings are all baked from #33.

The ride is still missing: the handle, the spline between the posts and the pose that goes with it. The seesaw's balance and the swing's pendulum are #113's mechanisms, and the sit pose they share is on the bench-sitting branch (#68).

The zip wire is in the world. Riding it is not. `playground=zipwire` now bakes as `PROP_ZIPWIRE` with a model (`dafe0e3`), so the cable's two posts stand on the campus and the one-of-its-kind node is worth looking for. The seesaw, the climbing frame, the slide and the swings are all baked from #33. The ride is still missing: the handle, the spline between the posts and the pose that goes with it. The seesaw's balance and the swing's pendulum are #113's mechanisms, and the sit pose they share is on the `bench-sitting` branch (#68).

sermuns added a new dependency

2026-10-25 02:47:15 +00:00

#113 Make the playground toys real mechanisms

sermuns referenced this issue

2026-10-26 09:01:54 +00:00

Swing between buildings on a grappling hook #240

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Ride the zip line and play on the playground #71