Motion 2.0 Preview 2

This second preview introduced the component-based Motion 2.0 architecture. It supports existing ACharacter subclasses, multiplayer, and GAS integration.

DANGER

IMPORTANT: Motion 2.0 Preview 2 is an architectural redesign. You cannot use it to upgrade a project from a previous version.

This breaking change makes a new integration necessary. The architecture simplifies later updates.

Universal Compatibility Achieved

Motion 2.0 Preview 2 successfully implements true universal compatibility:

• No Inheritance Necessary: Works with all ACharacter subclasses. Add Motion components to the character.
• Standard UE5 Components: Uses standard UCharacterMovementComponent and UAbilitySystemComponent
• Pure Component Composition: All functionality delivered through modular components
• Automatic Discovery: Components automatically find and integrate with necessary actors and systems

Component Architecture

Base Component System

• UMotionComponentBase: Foundation for all Motion components providing:

  • Automatic ASC initialization with retry mechanism (up to 20 attempts)
  • Input binding with retry system for multiplayer timing issues
  • Automatic component caching and discovery
  • Shared input binding and camera-curve identifier helpers

  Network RPC validation, rate limiting, and camera effects remain responsibilities of the derived components that use them.

Movement Components (All C++ with Blueprint exposure)

• UMotionBreathingComponent: Velocity-based camera breathing effects
• UMotionWalkComponent: Base movement speed and directional multiplier management
• UMotionSprintingComponent: Advanced sprint system with stamina and direction validation
• UMotionJumpComponent: Multi-jump support with coyote time and server validation
• UMotionCrouchingComponent: Hybrid crouch system with smooth transitions
• UMotionMovementSoundComponent: Surface-based audio with MetaSound integration

GAS Integration

• UMotionAttributeSet: Comprehensive attribute set with automatic CMC syncing

  • Movement: WalkSpeed, SprintSpeed, JumpVelocity
  • Stamina: Stamina, MaxStamina, StaminaRegenRate, StaminaDrainRate
  • WalkSpeed and JumpVelocity sync to CMC properties through attribute-change handlers
  • Full replication support with proper attribute macros

• AMotionPlayerState: Necessary for GAS persistence across respawns

  • Owns the AbilitySystemComponent for proper replication
  • Handles attribute initialization and persistence
  • Compatible with all GameModes when you set PlayerStateClass

Enhanced Camera System

• UMotionCameraComponent: Advanced first-person camera with:
  • Integrated curve evaluation system for location and rotation
  • Smooth camera-height interpolation with FMath::FInterpTo
  • Support for additive camera effects from all components
  • Ground-relative camera positioning during capsule-height changes

Multiplayer Improvements

Client Prediction and Server Reconciliation

• Hybrid Movement System: Combines UE5 built-in movement with component-owned GAS state and local response
• Immediate Response: Walk and sprint speed prediction plus native local crouch and jump response
• Server Authority: Server validates sprint, crouch, and jump requests
• Speed Reconciliation: Predicted walk and sprint speed state is reconciled when GAS attributes update

Network Optimizations

• GameplayEffect-based Tag Replication: Efficient state synchronization
• Crouch RPC Rate Limiting: Crouch validation enforces a per-component minimum request interval
• Smart Landing Detection: Resolves jump count synchronization issues
• Attribute-based Speed Sync: Direct CMC property updates via GAS

Stamina System

• Hysteresis Prevention: Smart exhaustion handling prevents sprint cycling
• Smooth Regeneration: Configurable delay and regen rate via attributes
• Multiplayer Ready: Full replication through GAS attributes

Critical Bug Fixes

Multiplayer Issues Resolved

• Fixed infinite jump exploit through proper server-side validation
• Resolved RPC processing failures preventing server execution
• Fixed sprint/crouch state conflicts causing animation issues
• Eliminated capsule sync issues causing camera stuttering
• Fixed GameplayEffect application failures on clients

Movement System Fixes

• Eliminated camera position jumps when crouching
• Fixed multi-jump direction with character velocity instead of input
• Resolved coyote time double-declaration
• Fixed stamina not properly sourcing from GAS attributes
• Corrected crouch speed penalty application

Input and Initialization

• Added retry mechanisms for input binding in multiplayer
• Fixed ASC initialization race conditions
• Resolved component discovery timing issues
• Added validation for all RPC requests

Included Gameplay Effects

Motion 2.0 Preview 2 includes pre-configured Gameplay Effects for all movement states:

Movement Speed Effects

• GE_Motion_WalkSpeed: Base walking speed modifier
• GE_Motion_SprintSpeed: Sprint speed increase
• GE_Motion_CrouchSpeed: Crouch speed reduction
• GE_Motion_JumpVelocity: Jump height modifier

State Tags

• GE_Motion_Walking, GE_Motion_Sprinting, GE_Motion_Crouching, GE_Motion_Jumping
• GE_Motion_WantsToSprint, GE_Motion_WantsToCrouch, GE_Motion_WantsToJump
• GE_Motion_BreathingActive: Camera breathing effect state

Stamina Effects

• GE_Motion_SprintStaminiaDrain: Continuous stamina consumption while sprinting (asset name as shipped in Preview 2)
• GE_Motion_SprintStaminiaRegen: Stamina regeneration when not sprinting (asset name as shipped in Preview 2)
• GE_Motion_SprintStaminiaRegenDelay: Delay before regeneration begins (asset name as shipped in Preview 2)

Migration Guide

To integrate Motion 2.0 Preview 2 into your project:

1. Remove Previous Versions: Delete all previous Motion content
2. Install Fresh: Add Motion 2.0 Preview 2 to your project
3. Configure GameMode: Set PlayerStateClass to AMotionPlayerState::StaticClass()
4. Add Components: Add desired Motion components to your character class
5. Setup Input: Bind Enhanced Input actions to Motion components
6. Configure GAS: Motion components will automatically integrate with your ASC

Known Issues

No Preview 2-specific known issues are listed in this changelog.