Fix character controller to go up stairs


Continuing the discussion from Beta release 14 comments:

This is an ongoing problem. At present it is not possible for an avatar to walk up a set of stairs unless the vertical stairstep separation is minimal. Even using primitive shapes does not work for more than 0.2m verticals, and then it tends to be nondeterministic if the strike angle is greater than 45 degrees, more or less. It would be really nice to get this one out of the way.

The use of an invisible ramp mitigation does not work well, because:

  • it mars the scene by having the avatar’s feet float well over the stair steps. In an HMD based view or in close-up machinima, it damages the verisimilitude of the world
  • The avatar slides downhill when they stop (stiction is not implemented, and no signs it ever will be)

IRL, people can walk up stairs easily with riser spacing up to 0.21m (the IBT standard is 7.75" 20cm). In practice people can climb stairs nearly up to their knee height (2.5ft 0.75m). 0.75m is Second Life’s standard “can climb” limit.

This request is to make the changes to permit avatars to walk up obstacles of up to 0.75m height. A bonus implementation would be to base the height limit on the avatar’s standing knee height. @Caitlyn


I think i would say 0./40cm is walk up soemthing. and 0.76 is climbing on something (withn animation. Secondlife have a range that’s a bit overdone.


We don’t yet have any sky-hook logic that would pull the avatar up when it walks into a step. Yes, this should be done, it just hasn’t been sorted to the front of the work queue yet. Its urgency is starting to increase now that we’ve got more content that we’d like to walk on, so I’ll probably try to take a swing at it after I complete this next iteration on making model objects collide correctly.

Avatar cant step up 10mm

Now that we can easily introduce decent physics shapes onto our content and our days of floating through things turned into days of walking on surfaces, it became evident :slight_smile: Looking forward to it!