This PR adds a define BVH_EXPAND_LEAF_AABBS which is set, which stores expanded AABBs in the tree instead of exact AABBs.
This makes the logic less error prone when considering reciprocal collisions in the pairing, as all collision detect is now taking place between expanded AABB against expanded AABB, rather than expanded AABB against exact AABB.
The flip side of this is that the intersection tests will now be less exact when expanded margins are set.
All margins are now user customizable via project settings, and take account of collision pairing density to adjust the margin dynamically.
(cherry picked from commit 211dc8cd2d)
Updating the broadphase to find new collision pairs was done after
checking for collision islands, so it was working in most cases due to
the pairing margin used in the BVH, but in case of teleported objects
the narrowphase collision could be skipped.
Now it's done before checking for collision islands, so we can ensure
that broadphase pairing has been done at the same time as objects are
marked as moved so their collision can be checked properly.
This issue didn't happen in the Octree/HashGrid because they do nothing
on update and trigger pairs directly when objects move instead.
(cherry picked from commit e9fdf3e61f)
In all physics servers, body_get_direct_state() now silently returns
nullptr when the body has been already freed or is removed from space,
so the client code can detect this state and invalidate the body rid.
In 2D, there is no change in behavior (just no more errors).
In 3D, the Bullet server returned a valid direct body state when the
body was removed from the physics space, but in this case it didn't
make sense to use the information from the body state.
(cherry picked from commit b93aeec4a2)
The BVH implementation is not checking collision layers on existing
pairs on move like other physics broadphases do.
This is solved by adding a new call to trigger pair callbacks again so
the physics engine can check layers again (specific to the BVH version,
other broadphase implementations just trigger a move like before).
These changes improve Rayshape behavior for Godot Physics 2D and 3D
when using move_and_slide with and without snapping.
Kinematic margin is now applied to ray shapes when handling snapping
collision tests and separation raycasts to help getting consistent
results in slopes and flat surfaces.
Recovery is calculated without the margin and a depth of 0 is still
considered a collision to stabilize results when on flat surface.
Recovery depth takes into account the current recovery vector (just like
test_body_motion) to fix jittering issues with multiple ray shapes due
to applying too much recovery.
Allows more flexible collision detection with different safe margin values.
Kinematic body motion changes in 2D and 3D:
-Recovery only for depth > min contact depth to help with collision
detection consistency (rest info could be lost if recovery was too much)
-Adaptive min contact depth (based on margin) instead of space parameter
When synchronizing KinematicBody motion with moving the platform using
direct body state, only the linear velocity was taken into account.
This change exposes velocity at local point in direct body state and
uses it in move_and_slide to get the proper velocity that includes
rotations.
In 3D, collision is disabled between kinematic/static bodies when
contacts are generated only to report them.
In 2D, this case was already fixed but the code is cleaned to make
it easier to follow.
* Safe and unsafe motion are calculated by dichotomy with a limited
number of steps. It's good for performance, but on long motions that
either collide near the beginning or near the end, the result can be
very imprecise.
* Now a factor 0.25 or 0.75 is used to converge faster when this case
happens, which allows longer motions to get more accurate collision
detection.
* Makes snap collision more precise, and helps with cases where diagonal collision on the border of a platform can lead to the character being stuck.
Additional improvements to move_and_slide:
* Handle slide canceling in move_and_collide with 0 velocity instead of
not applying it.
* Better handling of snap with custom logic to cancel sliding.
* Remove small jittering when using stop on slope, by canceling the
motion completely when the resulting motion is less than margin instead
of always projecting to the up direction (in both body motion and snap).
Co-authored-by: fabriceci <fabricecipolla@gmail.com>
Make sure the direction of the motion is preserved, unless the depth is
higher than the margin, which means the body needs depenetration in any
direction.
Also changed move_and_slide to avoid sliding on the first motion, in
order to avoid issues with unstable position on ground when jumping.
Co-authored-by: fabriceci <fabricecipolla@gmail.com>
Fixing by applying the movement in two steps, first the platform
movement, and then the body movement. Plus, add the platform movement
when we are on_wall.
In 3D, disabled shapes are now not added to the broadphase anymore.
Since they are removed right away when disabled, no need to check for
disabled shapes for any query that comes from the broadphase.
Also Fixes raycast queries returning disabled shapes.
In 2D, disabled shapes where already not added to the broadphase.
Remove the same unnecessary checks as in 3D.
Overall harmonized API for disabled shapes in the physics servers and
removed duplicate method.
Dynamic BVH doesn't update the tree anymore when calling set_pairable
with no parameter change.
Also modified Godot Physics broadphase to create objects directly with
pairable (static) set correctly to make use of this optimization for the
BVH broadphase.
Note: Octree broadphase doesn't use this optimization because it forces
an update on move, so passing the proper AABB and static parameters on
creation would cause the tree to update twice.
List of changes:
- Modified bvh class to handle 2D and 3D as a template
- Changes in Rect2, Vector2, Vector3 interface to uniformize template
calls
- New option in Project Settings to enable BVH for 2D Physics (enabled
by default like in 3D)
- Based on C++11's `atomic`
- Reworked `SafeRefCount` (based on the rewrite by @hpvb)
- Replaced free atomic functions by the new `SafeNumeric<T>`
- Replaced wrong cases of `volatile` by the new `SafeFlag`
- Platform-specific implementations no longer needed
Co-authored-by: Hein-Pieter van Braam-Stewart <hp@tmm.cx>
- Based on C++11's `thread` and `thread_local`
- No more need to allocate-deallocate or check for null
- No pointer anymore, just a member variable
- Platform-specific implementations no longer needed (except for the few cases of non-portable functions)
- Simpler for `NO_THREADS`
- Thread ids are now the same across platforms (main is 1; others follow)
- Based on C++11's `mutex` and `condition_variable`
- No more need to allocate-deallocate or check for null
- No pointer anymore, just a member variable
- Platform-specific implementations no longer needed
- Simpler for `NO_THREADS`
- Based on C++11's `mutex`
- No more need to allocate-deallocate or check for null
- No pointer anymore, just a member variable
- Platform-specific implementations no longer needed
- Simpler for `NO_THREADS`
- `BinaryMutex` added for special cases as the non-recursive version
- `MutexLock` now takes a reference. At this point the cases of null `Mutex`es are rare. If you ever need that, just don't use `MutexLock`.
- `ScopedMutexLock` is dropped and replaced by `MutexLock`, because they were pretty much the same.
This change makes test_body_motion more reliable when the kinematic body
recovers from being stuck.
- When recovery occurs, the rest information is generated, in order to
make sure collision results from test_move, move_and_collide and
move_and_slide are consistent and return a collision in case of overlap.
- The new calculation for recovery vector makes sure the recovery is
never more than the overlap depth between shapes.
This can help with cases where the kinematic body overlaps with several
shapes.
Recovery is made iteratively, without forcing a full overlap at each
step. This helps with getting proper rest information when recovery
occurs.
- One Way Collision:
When attempting motion, contact direction is checked against motion
before skipping in order to solve cases where kinematic bodies can sink
into one-way collision shapes.
Rest info now sets max contact depth in order to properly handle one-way
collision.
- Low speed motion is now handled in the rest info, by never setting
min_allowed_depth lower than motion length.
Separation is always applied with full margin, otherwise contact is lost
when low speed motion occurs right after higher speed motion.
- Similar changes are applied to 3D in order to make 2D and 3D
consistent.
Happy new year to the wonderful Godot community!
2020 has been a tough year for most of us personally, but a good year for
Godot development nonetheless with a huge amount of work done towards Godot
4.0 and great improvements backported to the long-lived 3.2 branch.
We've had close to 400 contributors to engine code this year, authoring near
7,000 commit! (And that's only for the `master` branch and for the engine code,
there's a lot more when counting docs, demos and other first-party repos.)
Here's to a great year 2021 for all Godot users 🎆
(cherry picked from commit b5334d14f7)
lawnjelly
PouleyKetchoupp
Rémi Verschelde
Rémi Verschelde
Daniel
fabriceci
Jordan Schidlowsky
Henry Conklin
Marcel Admiraal
Hein-Pieter van Braam
Pedro J. Estébanez