Move That Character: Launch, Shove, Teleport

In Part 1 we got a hold of the player's fort_character. Now we move it. A character moves three ways from Verse, each with its own personality:

Verb	Feel	Use it for
SetLinearVelocity	Hard, immediate	Launch pads, dashes — replace their motion
ApplyLinearImpulse	Soft, physics-y	Nudges, knockback — add to their motion
TeleportTo	Instant blink	Checkpoints, respawns, "you fell, go back"

We'll build a bounce pad with the first one, then meet the single gotcha that catches everybody.

The bounce pad: set an upward velocity

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Vertical Launch

SetLinearVelocity takes a vector3 in meters per second and replaces the character's current velocity. To pop a player straight up, you set only the vertical component:

# Pop straight up at 15 m/s.
Up := vector3{ Forward := 0.0, Left := 0.0, Up := 15.0 }
Body.SetLinearVelocity(Up)

Look closely at that vector3. The fields are Forward, Left, Up — not X, Y, Z.

The gotcha: two vector3 types, two sets of field names

This is the thing to internalize. UEFN ships two vector3 types, and they have different field names:

• /Verse.org/SpatialMath vector3 → fields are Forward, Left, Up (the modern Scene Graph convention — the same one you used in the Animation series).
• /UnrealEngine.com/Temporary/SpatialMath vector3 → fields are X, Y, Z (the older engine convention).

They are genuinely different structs, and different functions want different ones. SetLinearVelocity wants the /Verse.org/SpatialMath vector3 — so you write Forward/Left/Up.

The trap: if you using both SpatialMath modules in the same file, the name vector3 becomes ambiguous and the compiler refuses a bare vector3{...}. The fix is simple — import only the SpatialMath you need. For character velocity that's /Verse.org/SpatialMath, and then a plain vector3{ Forward := ..., Left := ..., Up := ... } just works.

using { /Verse.org/SpatialMath }   # gives the Forward/Left/Up vector3
# Do NOT also import /UnrealEngine.com/Temporary/SpatialMath here —
# two vector3s in scope makes `vector3{...}` ambiguous.

A softer option: shove instead of slam

SetLinearVelocity overwrites motion — a running player loses their forward speed and just goes up. If you want to add a push while keeping their momentum, use ApplyLinearImpulse (measured in Newton-seconds, a physics impulse):

# Add an upward shove without erasing their run — they arc forward.
Push := vector3{ Forward := 0.0, Left := 0.0, Up := Strength }
Body.ApplyLinearImpulse(Push)

Same axis fields, different feel: SetLinearVelocity is a launch pad; ApplyLinearImpulse is a gust of wind.

The full bounce-pad device

Notice the for (P : ..., Body := P.GetFortCharacter[]) — the failable bind sits right in the for-clause, so the loop body only runs for players who have a body. Clean.

And the third verb: TeleportTo

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Instant Teleport

The instant blink — Body.TeleportTo[Position, Rotation] — moves a character somewhere immediately. It's failable ([]): it fails if the spot is blocked or out of bounds, so you guard it. One wrinkle: TeleportTo wants the other vector3 (the /UnrealEngine.com/Temporary/SpatialMath one, with X/Y/Z), so mixing it with velocity code means dealing with both types. We sidestep that in the capstone by handing fallen players to a Teleporter device instead — cleaner, and no type juggling. For now, just know the verb exists and is failable.

This bounce-pad device is compile-verified in UEFN 5.8 (0 errors). Grab 03-device.verse, wire a Button into LaunchButton, and tune LaunchSpeed in the Details panel.

Recap

• A character moves three ways: SetLinearVelocity (replace motion), ApplyLinearImpulse (add a physics shove), TeleportTo (instant blink, failable).
• Gotcha: there are two vector3 types. The /Verse.org/SpatialMath one uses Forward/Left/Up; the Temporary one uses X/Y/Z. Importing both makes vector3 ambiguous — import only the one you need.
• For velocity/impulse, that's /Verse.org/SpatialMath → write Forward/Left/Up. Up is vertical, so an upward pop sets only Up.
• Put the failable GetFortCharacter[] right in the for-clause to fetch-and-filter in one line.

Next — Part 3: Reacting to the Player — instead of pushing characters, we listen to them: jumps, crouches, sprints, all broadcast as events.