Movers

Movers translate the processed movement input from the MoverContext into physics forces on the unit’s rigid body. Each mover activates for a specific named mode — when the MoverContext broadcasts MovementModeChanged("Free"), only the mover whose m_moveModeName matches "Free" activates. All others deactivate. This makes the locomotion system fully mode-driven and composable.

For usage guides and setup examples, see The Basics: GS_Unit.

Contents

• Class Hierarchy
• GS_MoverComponent (Base)
• GS_PhysicsMoverComponent
• Concrete Movers
• API Reference
• Extension Guide
• See Also

Class Hierarchy

GS_MoverComponent (base — mode-aware activation, tick management)
  └── GS_PhysicsMoverComponent (adds RigidBody cache + validity check)
        ├── GS_3DFreeMoverComponent    (mode: "Free")
        └── GS_3DSlideMoverComponent   (mode: "Slide")

GS_MoverComponent (Base)

Tick: AzPhysics::SystemEvents::OnPostSimulateEvent (after the physics step). Optional debugForceTick uses AZ::TickBus for debugging without physics.

Mode-Aware Activation

Listens to MoverContextNotificationBus::MovementModeChanged and RotationModeChanged. Compares the broadcast mode name against its own m_moveModeName and m_rotateModeName. Calls ToggleMovement(true/false) and ToggleRotation(true/false) accordingly. The physics post-simulate handler is only registered when the mover is active, saving ticks when inactive.

Per-Tick Processing

Each tick:

1. CheckCanOperate() — validates that the required pointers and state are valid
2. HandleMovement() — calculates and applies movement (no-op in base)
3. HandleRotation() — calculates and applies rotation (no-op in base)

Key Fields

GS_PhysicsMoverComponent

Extends GS_MoverComponent. On activate, fetches AzPhysics::RigidBody* from the entity. CheckCanOperate() verifies the rigid body pointer is valid before allowing tick processing.

Concrete Movers

API Reference

Movers consume two buses and produce one:

Consumed

Virtual Methods

Override these when extending any mover:

Extension Guide

Use the Mover ClassWizard template to generate a new mover with boilerplate already in place — see GS_Unit Templates. The template offers two base class options: Physics Mover (default) for rigid-body locomotion, and Base Mover for transform-only movement.

Extend GS_PhysicsMoverComponent to create a custom physics-driven mover.

#pragma once
#include <Source/Unit/Mover/GS_PhysicsMoverComponent.h>

namespace MyProject
{
    class MyCustomMover : public GS_Unit::GS_PhysicsMoverComponent
    {
    public:
        AZ_COMPONENT_DECL(MyCustomMover);
        static void Reflect(AZ::ReflectContext* context);

    protected:
        void Activate() override;

        void HandleMovement() override;
        void HandleRotation() override;

    private:
        // Mode name must be set in Activate():
        // m_moveModeName = "MyMode";
        // m_rotateModeName = "MyMode";
    };
}

In HandleMovement(), read from the MoverContext and write to the rigid body:

void MyCustomMover::HandleMovement()
{
    AZ::Vector3* groundedInput = nullptr;
    GS_Unit::MoverContextRequestBus::EventResult(
        groundedInput, GetEntityId(),
        &GS_Unit::MoverContextRequestBus::Events::GetGroundMoveInputAxis
    );

    if (!groundedInput || groundedInput->IsZero()) return;

    AZ::Vector3 targetVelocity = *groundedInput * activeProfile->moveSpeed;
    m_rigidBody->SetLinearVelocity(targetVelocity);
}

See Also

• Mover Context — Provides all input data movers read from
• GS_3DFreeMoverComponent — The standard free-locomotion mover
• GS_3DSlideMoverComponent — The slope-slide mover
• Grounders — Provide ground state and trigger mode switches
• Movement Profile — Asset defining speed and locomotion parameters

Get GS_Unit

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