Blueprint reference

Everything here is also available in C++. Nothing in this framework is C++-only.

The short way — ED Mounting library

Static nodes with the component lookup and the null checks folded in.

Node
Try Mount Nearest	Get into whatever is nearest. Two exec pins: Succeeded, Failed.
Try Mount	Get into a specific actor.
Try Dismount	Get out.
Toggle Mount	In if out, out if in. What a single key wants.
Get Rider Component / Get Mountable Component
Is Mountable	Whether an actor can be ridden right now.
Is Mounted / Is Seated / Is Driving Mount	Without a cast.
Get Mount Phase / Get Mount Actor / Get Seat Role / Get Occupied Seat
Find Nearest Mount	The full query, for an interaction prompt.
Make Default Mount Query	A query with the defaults filled in.
Get Failure Text	Localised text for any failure reason.
Get Seat Name	A seat's authored name, for UI.
Is Valid Seat Handle / Equal (Seat Handle) / To String (Seat Handle)

ED Rider component

Requests

Node
Request Mount	Get into an actor; the framework picks the seat and the door.
Request Mount With Options	The same with a full Mount Request struct.
Request Mount Nearest	Runs the registry query and mounts the winner.
Request Dismount
Request Change Seat	To a specific handle.
Request Shuffle Seat	To the next free seat, wrapping.
Force Dismount	Authority only. Put the rider down now, animation or not.
Apply Drive Input	Forward steering, throttle, brake and handbrake. Driver's seat only.
Handle Mount Event	Drive a transition moment yourself.

State

Get Mount Phase, Is Mounted, Is Seated, Is Transitioning, Is Driver, Get Mount Actor, Get Seat Handle, Get Entry Tag, Get Mountable, Get Seat Component, Get Seat Camera Component.

Events

Event	Fires
On Mount Phase Changed	Everywhere, including simulated proxies.
On Mount Failed	Only where the request was made.
On Mount Event	On every named transition moment.

Properties

Animation Set, Transition Mode, Default Query.

ED Mountable component

Seats

Get Seat Handles, Get Num Seats, Get Num Occupied Seats, Get Seat Component, Find Seat By Name, Get Driver Seat, Get Occupant, Find Seat Of, Get Driver, Get Riders, Is Seat Free, Has Free Seat, Get Seat World Transform.

Rules

Node
Can Rider Use Seat	Everything short of the distance check, with the reason.
Find Best Seat For	The seat a rider should get when they did not name one.

State

Is Mountable, Set Mountable (authority only), Get Mount Distance, Eject All Riders.

Events

On Seat Occupancy Changed, On Mount Event, On Mountable Changed.

Properties

Mount Tags, Mount Distance Override, Mount Animation Set, Eject Riders On Destroy.

ED Mount Point (Seat) component

Properties are listed in Seats. Nodes:

Get Seat Handle, Get Mountable, Get Seat Transform, Get Effective Seat Name, Is Driver Seat, Get Effective Entry Points, Get Entry Point Transform, Find Best Entry Point, Is Entry Point Clear, Resolve Animation Set, Resolve Rider Policy, Resolve Possession Policy, Get Seat Camera Component, Derive Side Tag.

Interfaces

Add them under Class Settings → Interfaces.

ED Mountable Interface — on the thing being ridden

Event
Can Accept Rider	The last word on whether this rider may take this seat. Runs on the server too.
On Rider Seated / On Rider Left	Authority only. Where gameplay state changes belong.
Set Seat Door Open	Called by door notifies, on every machine.
Apply Driver Input	Steering, throttle, brake, handbrake from the driver's seat.

ED Rider Interface — on the pawn

Event
Get Rider Tags	What a locked seat's query runs against.
Get Rider Mesh	Which mesh the montage plays on. Defaults to the first skeletal mesh.
On Mount Phase Changed	The same information as the delegate, as an overridable event.

All have working defaults. Implementing the interface is something you do when you want to change an answer, never something the framework requires.

Structs

Struct
Mount Request	Mount actor, desired seat, preferred entry, fallback, driver preference, instant, context tags.
Mount Result	Success, failure reason, seat, entry tag.
Seat Handle	The one way to name a seat.
Entry Point	A door: transform, side, priority, clearance, ground rules.
Mount Query	Distance, view angle, free-seat and reachability requirements, a tag query.
Mount Candidate	A query result: mount, seat, entry tag, distance, score.
Rider Policy	Collision, movement, replication, mesh, pose.
Procedural Transition	Duration, arc, easing curve, rotation.

Enums

Mount Phase, Mount Failure, Transition Mode, Possession Policy, Rider Collision Policy.