QuakelikeBody
A vaguely quake-like movement solver for Godot 3.
License
Creative Commons Zero, 1.0. See repository. In other words: public domain.
How to use
Drop QuakelikeBody.gd into your project, then use QuakelikeBody in the scene/node editor instead of KinematicBody. Then use velocity = custom_move_and_slide(delta, ...) instead of velocity = move_and_slide(...).
If you have jumping logic, set floor_collision to null when the character jumps.
Make sure your scripts say extends QuakelikeBody instead of extends KinematicBody.
Example
Used in the game jam games Still Waiting and Nostalgiac Blues.
Where's all the customization?
It's in the exported variables here:
All distances are Godot units.
FAQ:
Q: Why?
A: Because move_and_slide and move_and_slide_with_snap work in ways that bring out a lot of bugs in godot's physics backends (both bullet and godotphysics).
Q: My jumping code isn't working!
A: Set floor_collision to null in your jumping code. This movement solver decides whether to snap to the floor based on whether this variable is null or not.
Q: I'm hovering over the ground a little.
A: Reduce floor_search_distance until the hovering is unnoticable. A little hovering is unavoidable.
Q: My characters spawn a little above the ground even though they shouldn't be, what gives?
A: Increase floor_search_distance until this doesn't happen.
Q: I can't find a value of floor_search_distance that doesn't cause either of these problems!
A: Blame the weird bad way that Godot collision margins work, and hope that they get fixed in the future.
Q: I'm snagging on trimesh geometry when using an AABB/Cylinder.
A: Try enabling this flag in your project settings:
Q: Is this really a clone of quake's movement code?
A: No. It just coincidentally happens to take the same approaches to certain key things. I learned these approaches working on Gang Garrison 2, not Quake mods. There are many small differences, and it is not structured similarly on a code level. Naming it after Quake is just good advertising.