Build #138 - Can't climb out of Scourg Barrow coffin tunnel due to angled walls [RESOLVED 0.10.23]

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Interkarma
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Re: Build #138 - Can't climb out of Scourg Barrow coffin tunnel due to angled walls

Post by Interkarma »

Adding my test results to pango's.

Classic Daggerfall
  • North -Climbed out OK - note that north wall appears smooth and flat top to bottom
  • East - Stuck halfway or clipped through angled wall or fell into void
  • West - Stuck halfway or clipped through angled wall or fell into void
Daggerfall Unity (Advanced Climbing On & Off)
  • North - Stuck halfway - kind of slide up and down as opening narrows inward around player
  • East - Stuck halfway at angled wall, no clipping or falling through geometry
  • West - Stuck halfway at angled wall, no clipping or falling through geometry
It seems like we should be able to climb that north wall even in DFUnity. Possibly some of the other intelligence built in to climbing system such as mantling might be interfering. This happens whether Advanced Climbing is enabled or disabled.

I'll dig out an older version with the original climbing system and see if the problem is part of recent climbing updates.

Edit: Going back through older builds, I'm able to climb out the north surface up until 26 Aug 18. In builds after that date, I'm no longer able to climb out again. So this appears to be a fairly recent regression. Hopefully not so hard to fix then.

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Interkarma
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Re: Build #138 - Can't climb out of Scourg Barrow coffin tunnel due to angled walls

Post by Interkarma »

I've been able to isolate why this slightly angled wall is problematic to climb. Not surprisingly it's a combination of factors.

Firstly: In order to climb, the player must maintain constant contact with wall. To assist with this while climbing, a constant force towards wall is applied to ensure player maintains that contact. This also aids CharacterController physics that only samples collisions in the direction force is moving controller. Even when player is holding still on wall with advanced climbing, that force is pushing player towards wall.

Secondly: The climb out of coffin tunnel isn't flush vertically. The wall angles slightly towards player about half way up (like a subtle overhang). This overhang combined with force towards wall causes CharacterController to stick due to the somewhat flaky physics of this component. It basically creates an intersection that cancels movement direction and even pushes player backwards while trying to resolve the intersection.

So where it's getting stuck technically has nothing to do with the climbing system itself. The problem is actually one of physics handling in the CharacterController itself combined with the forces involved and the shape of the geometry player capsule is sliding against. There's no one easy answer here.

One hack is to increase the Skin Width of controller. This actually works so far as allowing player to climb that coffin tunnel, but it causes many other issues. The Skin Width is already oversized as it is and can't be increased further. This isn't a solution.

Another workaround is to remove the requirement of constant force and just allow player to move up/down from their starting position. This is similar to how old/classic climbing systems worked, and is why it was possible to climb this tunnel in older builds of DFU. But this would break advanced climbing which requires a very physical kind of simulation to swoop around corners and climb in any direction. Breaking that isn't a solution either.

It's likely that creating a custom character controller is the best all-round solution. This not only gives us full control over character movement (the existing CharacterController is a black box), it will help with solving a few other related problems with this controller, such as sticking on poorly made geometry in caves, or having to duck to exit Sentinel door ramp.

I'm not going to make any changes around this right now. I'm just going to let the problem digest a bit longer before pursuing what I believe is the best path. For now, please exit Scourg using magical means, such as the handy tapestry nearby.

BansheeXYZ
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Joined: Fri Oct 23, 2015 8:19 pm

Re: Build #138 - Can't climb out of Scourg Barrow coffin tunnel due to angled walls

Post by BansheeXYZ »

It doesn't really seem that you were intended to climb out in classic. The walls are sloped inward and there's a levitate buff nearby. It's just an overly hard puzzle of sorts, one that you could circumvent through a quirk in climbing.

Rather than messing with climbing and creating issues elsewhere, it seems like we just need to make the tapestry stand out more. Perhaps this is one instance where a hint should be added to the game, a message like "The tapestry looks worn and out of place..." when you get near it.

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Interkarma
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Re: [METEORIC DRAGON] Build #138 - Can't climb out of Scourg Barrow coffin tunnel due to angled walls

Post by Interkarma »

This is part of Meteoric Dragon's climbing changes. I don't have a good solution at this time. Will address when I am able.


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