Having slopes that end in a wall produces Tux to jitter

[Grumbel]

Original issue 3 created by SuperTuxTeam on 2010-02-21T10:11:55.000Z:

> What steps will reproduce the problem?

1. ./supertux data/levels/test/nightcave.stl
2. run into a wall
3. see Tux jitter

> What is the expected output? What do you see instead?
Tux should either stop or turn into a push-wall animation.

[Grumbel]

Comment #1 originally posted by SuperTuxTeam on 2014-01-30T13:34:13.000Z:

This should be fixed with de8c2e6.

[Grumbel]

Comment #2 originally posted by SuperTuxTeam on 2014-01-30T13:38:35.000Z:

Note here: I will leave the jump animation. Early apex for Tux shows a jump animation as well. So, it's very likely Tux just "tries" to do an early apex (it's a slope, after all) but fails.

[Grumbel]

Comment #3 originally posted by SuperTuxTeam on 2014-02-04T03:46:50.000Z:

Er... this does not appear to be entirely fixed. It does look better since Tux no longer alternates between walking and jumping, but it still looks awkward. In addition to the slight up-and-down motion, Tux has problems jumping while in the "jitter" state.

[tobbi]

This is fixed properly with c12910d.

We now set the on_ground flag even though Tux is slightly above the ground. This fixes the alternating states. Tux can now jump properly, it still jitters a little bit, but I think this fixes it better.

[tobbi]

This is a nightmare. Now Tux doesn't jitter but has problems jumping on sloped tiles.

[datahead8888]

What source file contains the geometry related code for the slope implementation? I was curious.

[tobbi]

Okay, so this issue is fixed with the commit above (c9ccb02). Again, we have a slight up-and-down movement (barely noticeable). If anyone wants to find the time to fix this properly (and knows what to do), just go ahead and do it.