Destructible Properties Matrix

Descriptions of all the properties on Destructible Actors in the DestructibleMesh Editor.


Destructible Mesh Category

Default Destructible Parameters Sub Category



Damage Parameters

Damage Threshold

The Damage amount which will cause a chunk to fracture (break free).

Damage Spread

Controls the distance into the destructible Actor to propagate the damage. The damage applied to the chunk is multiplied by Damage Spread to get the propagation distance.

Enable Impact Damage

Whether to apply damage to a destructible when colliding with an object.

Impact Damage

If a chunk is at a depth which has impact damage set, it will take damage equal to Impact Damage times the impact force when it collides with another object (assuming Report Rigid Collisions are enabled on both objects).

Custom Impact Resistance

By default objects that collide with destructibles will bounce back. Custom resistance allows for finer control of how much a destructible "pushes back" against a colliding object.

Impact Resistance

When a chunk takes impact damage due to physical contact, this parameter is the maximum impulse the contact can generate. Weak materials will have this set low, so heavier objects can pass through them during fracture. 0.0 is interpreted at infinite.

Default Impact Damage

Impact damage will be taken to this depth. If negative, impact damage is disabled.

Debris Parameters

Debris Lifetime Min

"Debris chunks" (see debris Depth, below) will be destroyed after a time (in seconds) separated from non-debris chunks. The actual lifetime is interpolated between these two bDebrisTimeout, based upon the module's LOD setting. To disable lifetime, clear the bDebrisTimeout flag in the flags field. If debrisLifetimeMax < debrisLifetimeMin, the mean of the two is used for both.

Debris Lifetime Max

Debris Max Separation Min

"Debris chunks" (see debris Depth, below) will be destroyed if they are separated from their origin by a distance greater than maxSeparation. The actual maxSeparation is interpolated between these two values, based upon the module's LOD setting. To disable maxSeparation, clear the bDebrisMaxSeparation flag in the flags field. If debrisMaxSeparationMax < debrisMaxSeparationMin, the mean of the two is used for both.

Debris Max Separation Max

Valid Bounds

"Debris chunks" (see debris Depth, below) will be destroyed if they leave this box. The box translates with the destructible Actor's initial position, but does not rotate or scale.

Advanced Parameters

Damage Cap

Limits the amount of damage applied to a chunk. This is useful for preventing the entire destructible from getting pulverized by a very large application of damage. This can easily happen when impact damage is used, and the damage amount is proportional to the impact force (see forceToDamage).

Impact Velocity Threshold

Large impact force may be reported if rigid bodies are spawned inside one another. In this case, the relative velocity of the two objects will be low. This variable allows the user to set a minimum velocity threshold for impacts to ensure that the objects are moving at a min velocity in order for the impact force to be considered.

Max Chunk Speed

If greater than 0, the chunks' speeds will not be allowed to exceed this value. Use 0 to disable this feature (this is the default).

Fracture Impulse Scale

Scale factor used to apply an impulse force along the normal of chunk when fractured. This is used in order to "push" the pieces out as they fracture.

Special Hierarchy Depths

Support Depth

The chunk hierarchy depth at which to create a support graph. Higher depth levels give more detailed support, but will give a higher computational load. Chunks below the support depth will never be supported.

Minimum Fracture Depth

The chunks will not be broken free below this depth.

Debris Depth

The chunk hierarchy depth at which chunks are considered to be "debris." Chunks at this depth or below will be considered for various debris settings, such as debrisLifetime. Negative values indicate that no chunk depth is considered debris.

Essential LOD Depth

The chunk hierarchy depth up to which chunks will always be processed. These chunks are considered to be essential either for gameplay or visually. The minimum value is 0, meaning the level 0 chunk is always considered essential.

Depth Parameters - Per Depth Level

Impact Damage Override

Chunks up to the depth set in Default Impact Damage Depth will take impact damage unless one of the override options is chosen.


Accumulate Damage

If set, chunks will "remember" damage applied to them, so that many applications of a damage amount below damageThreshold will eventually fracture the chunk. If not set, a single application of damage must exceed damageThreshold in order to fracture the chunk.

Asset Defined Support

If set, then chunks which are tagged as "support" chunks will have environmental support in static destructibles. Note: if both bAssetDefinedSupport and bWorldSupport are set, then chunks must be tagged as "support" chunks AND overlap the NxScene's static geometry in order to be environmentally supported.

World Support

If set, then chunks which overlap the NxScene's static geometry will have environmental support in static destructibles. Note: if both bAssetDefinedSupport and bWorldSupport are set, then chunks must be tagged as "support" chunks AND overlap the NxScene's static geometry in order to be environmentally supported.

Debris Timeout

Whether or not chunks at or deeper than the "debris" depth will time out.

Debris Max Separation

Whether or not chunks at or deeper than the "debris" depth will be removed if they separate too far from their origins.

Crumble Smallest Chunks

If set, the smallest chunks may be further broken down, either by fluid crumbles (if a crumble particle system is specified in the NxDestructibleActorDesc), or by simply removing the chunk if no crumble particle system is specified.

Accurate Raycasts

If set, the Raycast function will search within the nearest visible chunk hit for collisions with child chunks. This is used to get a better raycast position and normal, in case the parent collision volume does not tightly fit the graphics mesh. The returned chunk index will always be that of the visible parent that is intersected, however.

Use Valid Bounds

If set, the validBounds field of NxDestructibleParameters will be used. These bounds are translated (but not scaled or rotated) to the origin of the destructible Actor. If a chunk or chunk island moves outside of those bounds, it is destroyed.

Form Extended Structures

If this is set and the destructible is initially static, it will become part of an extended support structure if it is in contact with another static destructible that also has this flag set.

Fracture Effects - Per Depth Level

Particle System

The particle system to spawn when a chunk breaks.


The sound or sound cue to play when a chunk breaks.

For the Physics and Collision section of properties, see the Collision documentation.

Skeletal Mesh Sub Category



Materials - Per Element

Material Interface

The material to use for this element.

Enable Shadow Casting

Enables this material to cast shadows. Since this is on a per element level, and each fracture level can have a different material, you can turn off shadows at the smaller levels of a fractured object.

Force CPUSkinning

All skinning defaults to GPU skinning, this will force this destructible Actor to use CPU skinning.

Use Full Precision UVs

If true, this object will use 32bit UV's. If false, it will save memory by using 16bit UV's.

Texture Streaming Sub Category



Streaming Distance Multiplier

Allows artists to adjust the distance where textures using UV 0 are streamed in/out. 1.0 is the default, whereas a higher value increases the streamed in resolution.

Chunk Parameters Category

Chunks Sub Category



Is Support Chunk

Defines the chunk to be environmentally supported, if the appropriate NxDestructibleParametersFlag flags are set in NxDestructibleParameters.

Do Not Fracture

Defines the chunk to be unfracturable. If this is true, none of its children will be fracturable.

Do Not Damage

Defines the chunk to be undamagable. This means this chunk will not fracture, but its children might

Do not Crumble

Defines the chunk to be uncrumbleable. This means this chunk will not be broken down into fluid mesh particles no matter how much damage it takes. Note: this only applies to chunks with no children. For a chunk with children then: 1) The chunk may be broken down into its children, and then its children may be crumbled, if the doNotCrumble Flag is not set on them, 2) If the destructible module's chunk depth offset LOD may be set such that this chunk effectively has no children. In this case, the doNotCrumble flag will apply to it.

Fracture Settings Category

Voronoi Sub Category



Cell Site Count

The number of chunks that will be generated during the fracture process.

General Sub Category



Fracture Material Desc


The UV scale used by the internal material.


The UV origin offset for the internal material.


Object-space vector specifying surface tangent direction. If this vector is (0.0. 0.0, 0.0), then an arbitrary direction will be chosen.


Angle from tangent direction for the u coordinate axis.

Interior Element Index

The element index to use for the newly created triangles.

Random Seed

The seed that will be used by the random number generator to fracture the mesh.

Select Skin
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