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Lighting Arc

Lighting Arc

This feature is in preview release and is subject to change.

You can use the Lightning Arc component to create short arcs (also called sparks) between an emitter and a series of target entities. When an arc is emitted, the arc jumps between the center of the entity to which the Lightning Arc component is attached and the center of the target entity.

To enable the Lightning Arc component, you must enable the Lightning Arc gem. For more information, see Lightning Arc Gem.

Example
The Lightning Arc component is attached to the entity in the center, and the arc randomly jumps between three targets. This example uses the default lightning material in the Lightning Arc gem and the Tesla_core arc preset. For more information, see Customizing a Lightning Arc Preset.

[Add the Lightning Arc component to your entity to create lightning arcs that jump between entities.]

Topics

Lightning Arc Component Properties

The Lightning Arc component has the following properties:

Enabled
Specifies whether the Lightning Arc component emits arcs.

Targets
The collection of targets to which the Lightning Arc component emits arcs.

Material
The lightning arc material. This parameter does not require a specific type of material, but it’s recommended that you use the Illum shader and a texture with opacity.
You can find the default files in the following directory: Gems\LightningArc\Assets\materials\effects
Default value: None

Arc Preset Name
The name of the arc preset in use; the arc preset is specified in the lightningarceffects.xml file. If you change any of the arc parameters in this file, this field changes to <Custom>.
You can find the available arc preset names in the following directory: Gems\LightningArc\Assets\libs\lightningarc\lightningarceffects.xml

Refresh Presets
If you make changes to the lightningarceffects.xml file, click Refresh Presets to get the most recent arc preset names.

Arc Parameters

The Lightning Arc component has the following lightning options:

Contents

Lightning

Deviation
Amount of deviation applied to the arcs. Specify lower values to make the arc appear more smooth.

Fuzziness
Amount of noise applied to the arcs.

Velocity
Specify how fast an arc drifts upward after it is emitted.

Branch

The Lightning Arc component has following branch options:

Max Level
Maximum number of branches that can spawn from an arc. For more information, see SetBranchMaxLevel.

Probability
Specifies how likely that a child branch spawns from an arc. For more information, see SetBranchProbability.

Strike

The Lightning Arc component has following strike options:

Time Min
Minimum amount of time that an arc is kept alive.

Time Max
Maximum amount of time that an arc is kept alive.

Fade Out
Specifies how long it takes for an arc to fade out.

Segment Count
Number of segments in an arc. Specify more segments to make the arcs appear more winding.

Point Count
Number of points for each segment. Specify more points to increase the noise effect that is defined by the Fuzziness parameter.

Max Strike Count
Specify how many arcs can be alive at one time from this Lightning Arc component.

Beam

The Lightning Arc component has following beam options:

Size
The width of the arcs that the Lightning Arc component creates. The branches that spawn off the arc beam will have half this size.

Tex Tiling
Texture tiling based on the world size of the arc beam. For more information, see SetBeamTexTiling.

Tex Shift
Specify how fast to move through textures in the arc’s animation. For more information, see SetBeamTexShift.

Tex Frames
Specify how many frames are in the arc’s animation.

Tex FPS
Specify how many frames per second are in the arc’s animation.

Timing

The Lightning Arc component has following timing options:

Delay
Time between emitted arcs, in seconds.

Delay Variation
Variation in time between emitted arcs. For more information, see SetDelayVariation.

EBus Request Bus Interface

Use the following request functions with the EBus interface to communicate with other components of your game. You can use this EBus to communicate to an entity with a Lightning Arc component attached. The EBus is available at game run time and editing and can be accessed from C++, Lua, and the Script Canvas editor.

For more information about using the event bus (EBus) interface, see Working with the Event Bus (EBus) system.

Contents

Enable

Enables the component to emit lightning arcs.

Parameters
None

Return
None

Scriptable
Yes

Disable

Disables lightning arc emission.

Parameters
None

Return
None

Scriptable
Yes

Toggle

Toggles lightning arc emission.

Parameters
None

Return
None

Scriptable
Yes

IsEnabled

Returns whether the Lightning Arc component emits lightning arcs.

Parameters
None

Return
Type: Boolean

Scriptable
Yes

SetTargets

Sets the target entities to which the Lightning Arc component emits arcs.

Parameters
AZStd::vector<AZ::EntityId>
Type: Vector of entity IDs.

Return
None

Scriptable
Yes

GetTargets

Returns the target entities to which the Lightning Arc component emits arcs.

Parameters
None

Return
AZStd::vector<AZ::EntityId>
Type: Vector of entity IDs.

Scriptable
Yes

SetDelay

Sets the time between emitted arcs, in seconds.

Parameters
Type: Double

Return
None

Scriptable
Yes

GetDelay

Returns the time between emitted arcs, in seconds.

Parameters
None

Return
Type: Double

Scriptable
Yes

SetDelayVariation

Sets the variation in time between emitted arcs.

Delay variation is a random range applied to the Delay parameter to calculate the time that the next arc emits.

The random variation is in the following range: [delay variation * 0.5, delay variation].

For example, if the delay is 2.0 and the delay variation is 1.0, the range of time between arc emissions is [2.5 and 3.0].

Parameters
Type: Double

Return
None

Scriptable
Yes

GetDelayVariation

Returns the variation in time between emitted arcs.

Parameters
None

Return
Type: Double

Scriptable
Yes

SetStrikeTimeMin

Sets the minimum amount of time that an arc is kept alive.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetStrikeTimeMin

Returns the minimum amount of time that an arc is kept alive.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetStrikeTimeMax

Sets the maximum amount of time that an arc is kept alive.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetStrikeTimeMax

Returns the maximum amount of time that an arc is kept alive.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetStrikeFadeOut

Sets how long it takes for an arc to fade out.

Note
Lumberyard completes this fade out internally by scaling the size to 0 rather than adjusting the transparency.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetStrikeFadeOut

Returns how long it takes for an arc to fade out.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetStrikeSegmentCount

Sets the number of segments in an arc.

Specify more segments to make the arcs appear more winding. A Lightning arc component must have a minimum of 1 segment. If you specify 0, a warning appears and 1 is used instead.

Parameters
Type: AZ::u32

Return
None

Scriptable
Yes

GetStrikeSegmentCount

Returns the number of segments in an arc.

Parameters
None

Return
Type: AZ::u32

Scriptable
Yes

SetStrikePointCount

Sets the number of points for each segment.

Note
Specify more points to increase the noise effect that is defined by the Fuzziness parameter. A Lightning arc component must have a minimum of 1 point. If you specify 0, a warning appears and 1 is used instead.

Parameters
Type: AZ::u32

Return
None

Scriptable
Yes

GetStrikePointCount

Returns the number of points for each segment in an arc.

Parameters
None

Return
Type: AZ::u32

Scriptable
Yes

SetLightningDeviation

Sets the amount of deviation applied to the arcs.

Note
Specify lower values to make the arc appear more smooth.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetLightningDeviation

Returns the amount of deviation applied to the arcs.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetLightningFuzziness

Sets the amount of noise applied to the arcs.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetLightningFuzziness

Returns the amount of noise applied to the arcs.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetLightningVelocity

Sets how fast an arc drifts upwards after it emits.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetLightningVelocity

Returns how fast an arc drifts upwards after it emits.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetBranchProbability

Sets how likely a branch spawns off of an arc.

A branch (or child arc) is an arc that is half the size and intensity of the parent arc. A branch has the same emission point and target as its parent.

  • A value of 0 means that branches do not spawn.
  • A value of 0.5 means there is a 50% chance of spawning a branch.
  • A value of 2.0 means there is a 100% chance of spawning two branches.

For more information about setting the maximum number of branches, see SetBranchMaxLevel.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetBranchProbablity

Returns how likely a branch spawns off the parent arc.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetBranchMaxLevel

Sets the maximum number of branches that can spawn off the parent arc.

  • A value of 0 means branches do not spawn, regardless of branch probability.
  • A value of 3 means that between 0 and 3 branches can spawn, depending on the branch probability.

Parameters
Type: AZ::u32

Return
None

Scriptable
Yes

GetBranchMaxLevel

Returns the maximum number of branches allowed to spawn off the parent arc.

Parameters
None

Return
Type: AZ::u32

Scriptable
Yes

SetMaxStrikeCount

Sets how many arcs can be alive at one time from this Lightning Arc component; this includes parent and branch arcs.

Parameters
Type: AZ::u32

Return
None

Scriptable
Yes

GetMaxStrikeCount

Returns the maximum number of arcs that can be alive at one time from this Lightning Arc component.

Parameters
None

Return
Type: AZ::u32

Scriptable
Yes

SetBeamSize

Sets the width of the generated arcs. Branch arcs be half this size.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetBeamSize

Returns the width of the generated arcs.

Parameters
None

Return
Float

Scriptable
Yes

SetBeamTexTiling

Sets the texture tiling based on the world size of the arc beam.

  • A value of 2.0 means that the texture wraps around twice for each meter.
  • A value of 0.25 means that the texture wraps around four times for each meter.

Note
Only the U coordinate of the texture map is affected by this parameter.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetBeamTexTiling

Returns the texture tiling parameter for the arc beam.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetBeamTexShift

Sets how fast to move through textures in the arc’s animation.

Note
The U value of the texture coordinate moves at this specified rate. The V value is automatically calculated to select the correct frame.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetBeamTexShift

Returns how fast to move through textures in the arc’s animation.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetBeamTexFrames

Sets how many frames are in an arc’s animation.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetBeamTexFrames

Returns the number of frames in an arc’s animation.

Parameters
None

Return
Type: Float

Scriptable
Yes

SetBeamTexFPS

Sets how many frames per second are in an arc’s animation.

Parameters
Type: Float

Return
None

Scriptable
Yes

GetBeamTexFPS

Returns how many frames per second are in an arc’s animation.

Parameters
None

Return
Type: Float

Scriptable
Yes

Request Bus Example Script 

function example:OnActivate()
    -- Send some events to a LightningArcComponent attached to the same entity as this script
    LightningArcComponentRequestBus.Event.Toggle(self.entityId)
    LightningArcComponentRequestBus.Event.SetDelayVariation(self.entityId, 0.4)
end

EBus Notification Bus Interface

Use the following notification functions with the Lightning Arc component notification EBus interface to communicate with other components of your game.

For more information about using the Event Bus (EBus) interface, see Working with the Event Bus (EBus) system.

OnSpark

Notifies an event that triggers when the specified component fires a spark.

Parameters
None

Return
None

Scriptable
Yes

Notification Bus Example Script 

function example:OnActivate()
    -- Listen for lightning arc notifications on the same entity to which this script is attached
    self.lightningArcHandler = LightningArcComponentNotificationBus.Connect(self, self.entityId)
end
 
function example:OnSpark()
    Debug.Log("On Spark Triggered")
end
 
function example:OnDeactivate()
    self.lightningArcHandler:Disconnect()
end