Telegraphs

Documentation Unreal Engine Player Combat Telegraphs

Telegraphs warn the player about incoming attacks: a flare over a swing a guard can stop, a cross over an unblockable one, nothing over one that opens a counter, and markers over a stunned enemy.

Set it up

5 minutes

1
Create a style set
Content Browser
▸ Content
Right-click in the Content Browser, UPC, Targeting, Telegraph Style Set.
2
Add a row for the flare
Add a row to Styles. Leave Required Tags empty so it matches any attack, put UPC.Attack.Counterable (a label for an attack that opens a counter move of your own) in Blocked Tags so those attacks show nothing, and set Presenter Class (the Blueprint actor that draws the marker) to the demo's flare, BP_UPC_TelegraphPresenter_BlueLine (a soft yellow line).
TelegraphStyle_MyPlayer
▾Styles, Index [ 0 ]
Blocked Tags
Presenter ClassNone
An attack matching no row shows nothing.
3
Give the player a viewer
Add UPC Telegraph Viewer to the player character and set its Style Set to TelegraphStyle_MyPlayer. The demo's BP_UPC_Character carries one, set to TelegraphStyle_UPC_Default.
4
Mark the attack's windup
On the enemy's attack montage, add the Notify State UPC Telegraph Window across the windup, up to the swing's UPC Melee Trace Window, and tick Find The Attack Automatically so it describes the swing with that swing's own tags.
AM_MyEnemy_Attack
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
Notifies
UPC Telegraph Window
UPC Melee Trace Window
The marker lives as long as the telegraph window.
The window's Shape warns players within 500 cm in any direction, leaving the attacker's teammates out; the style set's View Rules add limits (Who is warned). Your new set has none.
5
Press Play and stand in front of the swing
Stand within 5 m before the enemy starts the attack: the flare shows over the windup and goes as the window closes.

Flare, cross or nothing

Each style row matches an attack by its tags; among matching rows the highest Priority wins, then the row listed first:

Row	Required Tags	Blocked Tags	Priority	Presenter Class
The cross	`UPC.Attack.Unblockable`		10	`BP_UPC_TelegraphPresenter_RedCross`
The flare		`UPC.Attack.Counterable`	0	`BP_UPC_TelegraphPresenter_BlueLine`

The defense reads the same tags off the attack. With UPC.Attack.Unblockable in the blocking Guard's Blocked Attack Tags and UPC.Attack.Unparryable in the parrying one's (Defense), the two rows give:

The attack carries	Marker	The guard stops it with
No attack tag	Flare	A block or a parry
`UPC.Attack.Unparryable`	Flare	A block
`UPC.Attack.Unblockable`	Cross	A parry
`UPC.Attack.Unblockable` and `UPC.Attack.Unparryable`	Cross	Nothing: the player dodges
`UPC.Attack.Counterable`, without Unblockable	None	What its other tags allow: Counterable only labels the attack and changes no guard rule

To keep the cross for attacks the player can only dodge, add UPC.Attack.Unparryable to the cross row's Required Tags. While a counterable attack winds up, its window holds UPC.Attack.Counterable on the attacker, which a counter move requires.

The same set with the two shipped View Rules added; a player must pass them and the window's 500 cm:

Details

TelegraphStyle_MyPlayer

Telegraph

Styles

2 Array elements

Index [ 0 ]

Required Tags

1 Gameplay Tag

UPC.Attack.Unblockable

Blocked Tags

0 Gameplay Tags

Priority

Presenter Class

BP_UPC_TelegraphPresenter_RedCross

Fallback Socket

None

Duration

Index [ 1 ]

Required Tags

0 Gameplay Tags

Blocked Tags

1 Gameplay Tag

UPC.Attack.Counterable

Priority

Presenter Class

BP_UPC_TelegraphPresenter_BlueLine

Fallback Socket

None

Duration

View Rules

2 Array elements

Index [ 0 ]

UPC Within Distance

Max Distance

1500

Index [ 1 ]

UPC Subject Facing Viewer

Arc Half Angle Degrees

An unblockable attack matches both rows and takes the cross, the higher Priority. An attack that is counterable, and not also unblockable, matches neither, so it shows nothing. Every other attack gets the flare.

Fallback Socket places the marker when the announcement names no socket; Duration sets the length for a one-frame announcement with none.

Mark the attack on the montage

Notify	Use it for
UPC Telegraph Window	A stretch of frames: a windup, or the seconds a stunned character is open to a finisher. Its tags sit on the character while it runs; the marker comes down as it closes.
UPC Telegraph	One frame with no end, such as a parry landing. Duration Seconds sets the marker's length, the style row's Duration when 0; it holds no tags.

Details

UPC Telegraph Window

Telegraph

Origin Space

Montage Mesh

Telegraph Type

Damage

Find The Attack Automatically

Setting	Does
Telegraph Type	Damage describes an incoming blow and takes the attack's tags; None describes a state with Tags alone.
Find The Attack Automatically	Reads the next UPC Melee Trace Window in this montage section: its Extra Damage Tags and its damage config's Damage Tags. Off by default.
Attack	With that off, the damage config described, for a grab with no trace window. Empty announces the window's Tags alone, so a feint warns about a blow it never lands.
Tags	Added to the attack's tags; under None, the whole description.
Origin Socket	Where the reach is measured from and the marker hangs; None uses the mesh's origin.
Shape, Team Filter	The ground it warns: a Sphere of Radius 500 cm, or a Cone with Half Angle Degrees (60) and Yaw Offset Degrees. Enemies Only leaves the attacker's teammates out. With no Shape, every player the style set passes sees it, wherever they stand.
Override Time To Impact	Set the countdown by hand, for a grab or a projectile launch with no trace window to measure.

Who is warned

One announcementEach viewer on this machine, step by step

An attack announces itself

a UPC Telegraph Window on the attacker's montage, or Show Marker

The window announces when the montage reaches it, on every machine playing that montage, with the tags it describes the attack by. Show Marker announces the same way on the machine that calls it.

A player on this machine is watching

UPC Telegraph Viewer, Style Set

Each viewer on a pawn a player on this machine controls, with a Style Set, is asked in turn. A character is never warned about its own attack, and an AI pawn is never a viewer.

The attack reaches the player

the window's Shape and Team Filter

A window with a shape warns only a player standing inside it whom its Team Filter lets through. With no shape, every viewer goes on to the next step.

A style row matches

Styles: Required Tags, Blocked Tags, Priority

The highest Priority row matching the attack's tags. No row, no marker.

Every view rule agrees

View Rules

Close enough, aimed the player's way, or whatever a rule of your own asks. An empty list agrees to everything.

The marker goes up

the row's Presenter Class, at the Origin Socket or the row's Fallback Socket

The presenter spawns on the socket and Begin Telegraph runs, then Update Telegraph each frame until the window closes or the marker's length runs out, then End Telegraph. A one-frame notify with no length anywhere, or a weapon stowed before this step, draws nothing.

A player who starts watching while a window is still open, such as one who respawned or was given a new style set, is shown that warning too.

The first step that says no means no marker; the window's 500 cm reach is the first, the View Rules follow. The steps run as the window opens, so a player who walks out of range keeps the marker. A player 3 m behind the attacker passes the 500 cm test and the distance rule, and the facing rule refuses it.

The View Rules that ship:

Rule	Warns only about
UPC Within Distance	Attackers within Max Distance (1500 cm).
UPC Subject Facing Viewer	Attackers facing the player, within Arc Half Angle Degrees (75; 180 turns it off) of their forward.

For another rule, such as warning only about the locked-on enemy, make a Blueprint child of UPC Telegraph View Rule and override Should Show, which gets the announcement and the player's pawn.

Make a marker

A marker is a Blueprint child of UPC Telegraph Presenter holding the particle system or widget, named on a style row. It spawns on the socket the warning names and rides the swing; each warned player gets their own.

BP_MyTelegraphMarker · Event Graph

Telegraph

TargetNiagara

Reset

Normalized Time

Seconds to Impact

Event	Runs
Begin Telegraph	As the marker goes up, with the announcement: Subject, mesh, socket, Tags, Time to Impact. Start the effect.
Update Telegraph	Each frame, with Normalized Time (0 to 1 across the windup, 1 as the swing starts sweeping) and Seconds to Impact.
End Telegraph	As the warning ends: the window closed or was cut, its length ran out, Hide Marker, a style set change, or the attacker or weapon went away. The actor goes right after, so a fade plays from a copy spawned here.

Both follow the montage, so a slowed attack keeps them right. A marker with no swing to time against runs them across its own length; with neither they stay 0, so treat 0 as unknown.

Put the marker on the weapon

Set the window's Origin Space to Drawn Item and Origin Socket to a socket on the weapon's mesh, so a blade flare rides the blade. Origin Item Tag picks the item, the one driving combat when unset. For a two-weapon attack, one window per weapon, name a tag from the other item's Equipment Tags. Two drawn items sharing a tag answer with the one drawn first. When the item is not drawn or lacks the socket, the marker falls back to the character's mesh in silence, and a weapon put away mid-windup takes its marker with it.

Put a marker over a character

Add UPC Telegraph Subject to any actor with a skeletal mesh and call Show Marker for a circle over a stunned enemy or a flare on a weak point.

BP_MyEnemy · when it is stunned

UPCTelegraphSubject

Target

TagsUPC.State.Staggered

Sockethead

Seconds3.0

Return Value

Tags is what the style rows match, Socket where the marker sits (the row's Fallback Socket when None), and Seconds how long it stays; 0 lasts until Hide Marker with the returned handle, or Hide All Markers. Each player's style set and view rules still decide what shows, and the actor's own player never sees its markers.

The style set needs a row for the marker's tag, or the catch-all flare answers it. For UPC.State.Staggered, add a row with that tag in Required Tags, a Priority above the flare's 0, and a presenter such as the demo's BP_UPC_TelegraphPresenter_Executable rings. Show Marker draws on the calling machine only (What runs where).

For a state the animation already plays, a UPC Telegraph Window with Telegraph Type None and the state's tag does the same from the montage, holding the tag while it runs; the demo's AM_UPC_Stun raises UPC.State.Staggered this way.

Debug it

LogUPCTelegraph warns once per cause, and Troubleshooting lists each with its fix.

AlternativeDraw the warning in the HUD instead

The viewer fires On Telegraph Shown (the Subject, the attack's Tags, the Presenter) and On Telegraph Hidden (Subject and Presenter), also for a row with no Presenter Class, so a HUD can draw its own marker. One attacker can raise several warnings at once, one per weapon, so count per Subject and remove the element at zero. Set Style Set swaps the set at runtime and takes down the old set's markers, none turning warnings off; Get Style Set reads it. Is Viewing answers whether a player on this machine controls the pawn, the only case drawn.

The demo

TelegraphStyle_UPC_Default adds a counter marker for counterable attacks.

Marker	Draws
`BP_UPC_TelegraphPresenter_BlueLine`	The soft yellow flare, `NS_UPC_AttackNotifier_Soft`.
`BP_UPC_TelegraphPresenter_RedCross`	The unblockable cross, `NS_UPC_AttackNotifier_Unblockable`.
`BP_UPC_TelegraphPresenter_Counter`	The counter marker, the flare in blue, `NS_UPC_AttackNotifier_Counter`.
`BP_UPC_TelegraphPresenter_Executable`	Rings over a character open to an execution, `NS_UPC_ExecutionPrompt_Rings`.

MultiplayerWhat runs where

Nothing replicates: each machine draws warnings for its own players from the montages it plays. A dedicated server draws none and loads no presenter.
Show Marker raises a marker on the calling machine only; for every player, call it from something each machine receives, such as a replicated tag or a gameplay cue.
Each player's machine runs the team test, so put the attacker's UPC Team on the pawn, not its AI controller. Exclusions changed at runtime on the server do not reach clients.

C++C++

Announcements go out through UPCTelegraph::OnBegin() with an FUPCTelegraph, and UPCTelegraph::OnEnd() follows when a window or a Show Marker ends; a one-frame notify sends no end. Both are process-wide, so check the Subject's world: two Play In Editor sessions share them. UUPCTelegraphSubsystem listens for the viewer.
FUPCTelegraph carries Subject, Mesh, OriginSocket, Type, Tags, TimeToImpact, bAwaitsExplicitEnd, DurationSeconds, OriginComponent, Origin, Direction, Magnitude, Broadcast and Payload.
A view rule overrides UUPCTelegraphViewRule::ShouldShow_Implementation(const FUPCTelegraph&, APawn* Viewer) const; a presenter overrides BeginTelegraph_Implementation, UpdateTelegraph_Implementation and EndTelegraph_Implementation.
IUPCTelegraphOriginProvider::GetTelegraphOriginActor is a Blueprint native event. UUPCEquipmentManagerComponent answers by GetInstanceByTag or GetCombatDriverInstance; the window asks the pawn, then its first component implementing it.

AdvancedTroubleshooting

Warning says	Fix
asked for a marker with no length	Set the one-frame notify's Duration Seconds or the row's Duration.
was still loading when a warning went up	Assign the style set before combat; the viewer loads its markers on assignment.
found no skeletal mesh to hang a marker on	Give the actor with UPC Telegraph Subject a skeletal mesh.
which the attack it describes does not carry	The window's Tags promise what the attack lacks; put the tag on the trace window or the damage config. For a feint, untick Find The Attack Automatically and clear Attack.
found no melee trace window after it	Add a trace window after it in its section, or tick Override Time To Impact.

No marker showed up

In order:

No viewer, or no Style Set. An AI pawn is never a viewer, so a map with no player shows nothing.
The player made the attack.
Out of reach, or a teammate under Enemies Only, judged as the window opens.
No row matches the attack's tags. With Find The Attack Automatically off and no Attack, the window carries only its own Tags.
A view rule refused: a player behind the attacker, or beyond Max Distance.
The row has no Presenter Class.
The montage plays in an editor preview, which runs no game world.