Important
Net-predicted soft organic collisions!
Eliminate multiplayer de-sync when moving near other pawns
Collisions that feel great for the best player experience possible!
Tip
Suitable for both singleplayer and multiplayer games
Push Pawn leverages GAS for net prediction.
With the default Unreal implementation, if two characters touch on the server -- so you might not even see it! -- a drastic desync occurs. 😵
But with PushPawn, no desync occurs regardless of high latency! 🤩
Note
Push Pawn has a lightweight and highly optimized implementation that is proven in production.
The included Push Ability applies a force over a short amount of time.
Walking into another pawn is very much like walking into a human in the real world! We can push past them or push them out of the way. We can even make them get angry! 🤬
Most importantly, we're not experiencing the effect of running into a brick wall 😣 which is Unreal's default collision for Pawns.
Capsule, Box, Sphere collisions are all supported for Pawn vs Pawn collisions
Tip
Characters are Pawns -- Push Pawn supports custom collision shapes even with Character Movement Component!
Of course, this doesn't affect their navigation nor interaction with the environment
Push Abilities can respond to gameplay events and trigger their own events. 😤
Note
Push Pawn can drive gameplay systems, it is not merely cosmetic.
Tip
Play a "shove" anim montage
Implement procedural skeletal physics so their body physically reacts to being bumped
Make your NPCs yell at the player when they run into them too fast!
When a group of NPCs attack a player, they often get in the way 💀 With Push Pawn they will push past each other with no extra work for you beyond setting up Push Pawn itself!
Is another player blocking a door you want to pass through? No problem, we can push past them also!
Or perhaps you'd like to be able to push AFK players off cliffs... 😈
One day, someone is going to do something surprising with Push Pawn, and I look forward to it, because the possibilities to adjust behaviour really are endless. That someone might be you! 😺
Warning
Due to the use of Git LFS, do not download a zip or your content will be missing
You will need to clone this via git clone https://github.com/Vaei/PushPawn.git
Examples are based on 1.0.0
Here is the preview from the included minimal Third Person Example project. This footage was obtained with >200ms and p.netshowcorrections 1 - as you can see, it doesn't de-sync abnormally.
This was initially created for a personal project that would make the AI play a push animation and yell at the player, which is not included, however the helper functions for building this are included.
No longer in beta following meaningful testing
- Fixed potential GC leak with WaitNetSync
- Added custom WaitNetSync (UAbilityTask_PushPawnSync) that passes itself with the callback to allow TArray cleanup
- Added distance based scaling to make characters firmer, if desired
- Added non-shipping CVars to disable both velocity and distance based scaling
- Add missing null checks for UPushStatics::GetPushPawnsFromEventDataChecked
- Add GetWorld() checks for AbilityTask_PushPawnScan
- Add WaitNetSync setting to sync without any pushes
- Add CVar p.PushPawn.Disabled to disable pushing
- Change timer to WeakLambda
- Fix up includes
- Change from pre-processor ENABLE_DRAW_DEBUG to UE_ENABLE_DEBUG_DRAWING
- Remove separate ability-granting task and move into scan task
- Removed final from UPushPawn_Action and noted the expectation to mark yours as final
- Add UAbilityTask_PushPawnForce
- This properly ends abilities when root motion source expires
- Very lightweight compared to engine tasks that replicate unnecessarily (for PushPawn)
- Add helper GatherPushOptions to UPushStatics
- Output ShapeRotation from GetPusheeCollisionShape for rotated shape support
- Export FPushQuery & FPushOption
- Preliminary completion of blueprint support
- Add UPusheeTargetComponent
- Migrate commonalities to UPushPawnComponent
- Wrap UPushStatics::GetPushPawnScanRange return statement for Linux compiler
- Change LoadingPhase to PreDefault
- Add support for horizontal capsule collisions
- Wait Net Sync properties moved to sub-category and AdvancedDisplay
- Added advanced disable feature for Wait Net Sync
- Fix not applying rotation to box scan
- Fix using default shapes without scale
- Refactor PusherRadiusScalar to PusheeRadiusScalar & Accel equivalent - oops
- Switch from ClearTimer to ClearAllTimersForObject in ability tasks
Blueprint
- Add K2_UpdatePawnOwner as a cache-point for PusheeComponent
- Added FromCollisionShape to FPushPawnCollisionShapeHelper
- Add K2_GetDefaultPusheeCollisionShape to UPusheeComponentHelper for BP only user convenience
- Renamed curve to include
Actionkeyword - Added additional curve for scanning and assigned by default
- Default to 2D direction for scanning
- Auto-Activate scan ability when granted by default
- FPushPawn namespace renamed to FPushPawnCVars
- Add debug drawing for PushPawn_Action "p.PushPawn.Action.Debug.Draw"
- Fix bug with checking diff post-normalization instead of pre-normalization
- ActivatePushPawnAbility returns a bool so we can ensure Super didn't end the ability (returns false)
- Remove redundant and now deprecated SetMovementSyncPoint
- PushPawn now compatible with blueprint only projects
- Added optional UPusheeComponent
- Extended UPusheeComponentHelper to implement BP-exposed IPusheeInstigator interface
- Added UPushStatics::GetPusheeInstigator as a central method for retrieving IPusheeInstigator
- Rename BlueprintDemo folder to Blueprints
- Add PushPawnEditor module
- Add Details Customization to hide properties we removed support for in our lightweight base ability
- Or irrelevant properties
- Support non-capsule collision shapes to allow for Pawn v Pawn collisions to use custom shape types such as boxes
- Remove dependency on ACharacter/UCharacterMovementComponent
- Built-in Push ability still maintains this dependency because it uses root motion sources
- Acceleration is always normalized with Mover's MovementIntent in mind
- Remove searching for UCapsuleComponent* as root
- Add UPushStatic getters using IPusheeInstigator instead of APawn to reduce casting
- Add IPusheeInstigator::GetPusheeCapsuleShape() allowing non-capsule root components, as well as using a capsule that doesn't represent the collision
- Add IPusheeInstigator::GetPusheeVelocity() to remove need to casting to Pawn to get it
- Added sanity checks for 0 scan range
- Refactor ability tasks
- AbilityTask_WaitForPushTargets ➜ UAbilityTask_PushPawnScan_Base
- UAbilityTask_WaitForPushTargets_CapsuleTrace ➜ UAbilityTask_PushPawnScan
- UAbilityTask_GrantNearbyPush ➜ UAbilityTask_GrantPushAbility
- Ability itself pauses along with the scan ability, aimed at preventing ASC from continuing to tick, pending testing
- Possible engine crash fix for ability tasks
BREAKING CHANGES
Significant perf improvements
-
Overhauled the internal system
- Created lightweight ability classes with details customization to reduce perf overhead
- PushPawn_Ability as the parent class for all abilities
- PushPawn_Scan_Base
- PushPawn_Ability_Base
- Created C++ variations of classes to remove overhead from BP VM
- PushPawn_Scan
- PushPawn_Ability
- Content is included primarily for example purposes and non-C++ users
- Previous ability classes have been removed, including the corresponding content
- GameplayAbility_Push_Scan removed in favour of PushPawn_Scan_Base, UPushPawn_Scan_Core, and PushPawn_Scan
- Instead of sending the direction as an FHitResult's Normal, a lighter class with only a normal vector has been added (FPushPawnAbilityTargetData)
- Added pre-activation interface checks that don't require pusher - use to check if alive, etc. to prevent activation entirely
- IPusheeInstigator: CanBePushed() refactored to CanBePushedBy(), and IsPushable() added
- IPusherTarget: CanPush() refactored to CanPushPawn(), and IsPushCapable() added
- Added TRACE_CPUPROFILER_EVENT_SCOPE throughout for profiling
- Added IPusheeInstigator::GetPushPawnScanPausedDelegate() that can be used to conditionally disable scanning when no one is nearby
- Created lightweight ability classes with details customization to reduce perf overhead
-
Improved synchronization
- Scan task awaits net sync intermittently, see UPushPawn_Scan_Base::ShouldWaitForNetSync() and ConsumeWaitForNetSync() to customize behaviour
-
Quality of life changes
- Improved overall feel of default values
- Added FPushPawnActionParams & FPushPawnScanParams structs
- Improved handling for runtime parameters
- Overhauled handling of scan rate and range to allow for runtime changes based on acceleration
- Added PushPawnTags to better define reusable native gameplay tags
- Categories changed from Push to PushPawn
- General refactoring to improve readability
- Improved code comments throughout
- Add Icon
If you're on 1.2.0 you need to update
- Refactor GA_Push_x to GA_PushPawn_x
- Push force curve no longer normalized, better defaults set
- Fixed bug where valid direction wasn't obtained when on top of each other
- Update blueprint content with changes
- Brought forward fixes from 1.2.0 that were accidentally not fully implemented or missed - if on 1.2.0 you must update
- Enabled gravity during root motion force by default
- Added helper functions to GA_PushPawn_Action
- Fix major init order bug
- Add radius scaling under acceleration
- Add radius scaling under velocity
- Add separate scan rate under acceleration
- Remove unused scan range
- Fix starting ability before actor has begun play
- Switch to Cvar to show debug
- Add missing include
- Move static helpers from
GameplayAbility_Push_ActiontoPushStatics - Fix include paths and const correctness
- Add inline cpp includes
- Initial Release