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Source: Roblox Creator Hub · CC BY 4.0 · View source · Code samples: MIT Imported 2026-10-03. Formatting adapted for this site.

ValueCurve

Inherits from: Instance → Object

An instance representing a 1D value curve encoded via a sorted list of ValueCurveKeys. The shape of the interpolation curve between two keys is determined by the ValueCurveKey.Interpolation type.

Not all value types (for example, strings and other non-numerical types) may perform Linear or Cubic interpolation. These types will revert to Constant interpolation if necessary.

Inherits from: Instance

Memory category: Instances

Properties

NameType / ReturnsDescription
ValueCurve.LengthintNumber of keys in the value curve.
ValueCurve.ValueTypestringRead-only value indicating the type held in this curve.

Inherited from Instance

NameType / ReturnsDescription
Instance.ArchivablebooleanDetermines if an Instance and its descendants can be cloned using Instance:Clone(), and can be saved/published.
Instance.archivableboolean
Instance.CapabilitiesSecurityCapabilitiesThe set of capabilities allowed to be used for scripts inside this container.
Instance.IsInSandboxbooleanIndicates whether the instance is inside a sandboxed container.
Instance.NamestringA non-unique identifier of the Instance.
Instance.ParentInstanceDetermines the hierarchical parent of the Instance.
Instance.PredictionModePredictionModeReflects the client-side prediction mode applied to the instance under server-authoritative physics.
Instance.RobloxLockedbooleanA deprecated property that used to protect CoreGui objects.
Instance.SandboxedbooleanWhen enabled, the instance can only access abilities in its Capabilities list.
Instance.UniqueIdUniqueIdA unique identifier for the instance.

Inherited from Object

NameType / ReturnsDescription
Object.ClassNamestringA read-only string representing the class this Object belongs to.
Object.classNamestring

ValueCurve.Length

Number of keys in the value curve.

FieldValue
typeint
tags["ReadOnly","NotReplicated"]
security{"read":"None","write":"None"}
thread safetyReadSafe
categoryData
serialization{"can_load":false,"can_save":true}
capabilities["Basic"]

ValueCurve.ValueType

Read-only value indicating the type held in this curve, or the string "Nil" if there are no keys.

FieldValue
typestring
tags["ReadOnly","NotReplicated"]
security{"read":"None","write":"None"}
thread safetyReadSafe
categoryData
serialization{"can_load":false,"can_save":true}
capabilities["Basic"]

Methods

NameType / ReturnsDescription
ValueCurve:GetKeyAtIndexValueCurveKeyReturns a copy of a key at a given index.
ValueCurve:GetKeyIndicesAtTimeArrayReturns the index of the last and first key of a period of time.
ValueCurve:GetKeysArrayReturns a copy of all the keys in the ValueCurve as a Luau array of ValueCurveKeys.
ValueCurve:GetValueAtTimeVariant?Samples the value curve at a given time passed as argument.
ValueCurve:InsertKeyArrayAdds the key passed as an argument to this curve. If a key at the same time is found, it will be replaced.
ValueCurve:InsertKeyValueArrayCreates a key for the given value and inserts it at the given time. If a key at the same time is found, it will be replaced.
ValueCurve:RemoveKeyAtIndexintRemoves a given number of keys starting from a given index.
ValueCurve:SetKeysintResets this curve's keys using the ValueCurveKey array passed as an argument.

Inherited from Instance

NameType / ReturnsDescription
Instance:AddTag()Applies a tag to the instance.
Instance:childrenInstancesReturns an array of the object's children.
Instance:ClearAllChildren()This method destroys all of an instance's children.
Instance:CloneInstanceCreate a copy of an instance and all its descendants, ignoring instances that are not Archivable.
Instance:cloneInstance
Instance:Destroy()Sets the Instance.Parent property to nil, locks the Instance.Parent property, disconnects all connections, and calls Destroy() on all children.
Instance:destroy()
Instance:FindFirstAncestorInstance?Returns the first ancestor of the Instance whose Instance.Name is equal to the given name.
Instance:FindFirstAncestorOfClassInstance?Returns the first ancestor of the Instance whose Object.ClassName is equal to the given className.
Instance:FindFirstAncestorWhichIsAInstance?Returns the first ancestor of the Instance for whom Object:IsA() returns true for the given className.
Instance:FindFirstChildInstance?Returns the first child of the Instance found with the given name.
Instance:findFirstChildInstance
Instance:FindFirstChildOfClassInstance?Returns the first child of the Instance whose ClassName is equal to the given class name.
Instance:FindFirstChildWhichIsAInstance?Returns the first child of the Instance for whom Object:IsA() returns true for the given className.
Instance:FindFirstDescendantInstance?Returns the first descendant found with the given Instance.Name.
Instance:GetActorActor?Returns the Actor associated with the Instance, if any.
Instance:GetAttributeVariantReturns the value which has been assigned to the given attribute name.
Instance:GetAttributeChangedSignalRBXScriptSignalReturns an event that fires when the given attribute changes.
Instance:GetAttributesDictionaryReturns a dictionary of the instance's attributes.
Instance:GetChildrenInstancesReturns an array containing all of the instance's children.
Instance:getChildrenInstances
Instance:GetDebugIdstringReturns a coded string of the debug ID used internally by Roblox.
Instance:GetDescendantsInstancesReturns an array containing all of the descendants of the instance.
Instance:GetFullNamestringReturns a string describing the instance's ancestry.
Instance:GetStyledVariantReturns the styled or explicitly modified value of the specified property, or else the default property value if it hasn't been styled/modified.
Instance:GetStyledPropertyChangedSignalRBXScriptSignalReturns an event that fires when the given style property changes on the instance.
Instance:GetTagsArrayGets an array of all tags applied to the instance.
Instance:HasTagbooleanCheck whether the instance has a given tag.
Instance:IsAncestorOfbooleanReturns true if an Instance is an ancestor of the given descendant.
Instance:IsDescendantOfbooleanReturns true if an Instance is a descendant of the given ancestor.
Instance:isDescendantOfboolean
Instance:IsPropertyModifiedbooleanReturns true if the value stored in the specified property is not equal to the code-instantiated default.
Instance:QueryDescendantsInstancesReturns an array containing all descendants of the instance that match the selector string.
Instance:Remove()Sets the object's Parent to nil, and does the same for all its descendants.
Instance:remove()
Instance:RemoveTag()Removes a tag from the instance.
Instance:ResetPropertyToDefault()Resets a property to its default value.
Instance:SetAttribute()Sets the attribute with the given name to the given value.
Instance:WaitForChildInstanceReturns the child of the Instance with the given name. If the child does not exist, it will yield the current thread until it does.

Inherited from Object

NameType / ReturnsDescription
Object:GetPropertyChangedSignalRBXScriptSignalGet an event that fires when a given property of the object changes.
Object:IsAbooleanReturns true if an object's class matches or inherits from a given class.
Object:isAboolean

ValueCurve:GetKeyAtIndex

Returns a copy of a key at a given index.

Parameters

NameTypeDefaultDescription
indexintThe index in the existing set of keys held by this ValueCurve.

Returns

TypeDescription
ValueCurveKeyA copy of the ValueCurveKey stored at the given index.
FieldValue
securityNone
thread safetyUnsafe
capabilities["Basic"]

ValueCurve:GetKeyIndicesAtTime

The first item in the returned array is the index of the last key with time less than or equal to time (or the lesser of either 1 or the curve length if no key was found). The second item in the returned array is the index of the first key with time greater than or equal to time (or the curve length if no key was found satisfying the inequality).

Parameters

NameTypeDefaultDescription
timefloatA time during the animation. Inputs will be clamped between 0 and the time of the last key held by this ValueCurve.

Returns

TypeDescription
ArrayAn array of two indices bracketing time: the index of the last key at or before time, and the index of the first key at or after time.
FieldValue
securityNone
thread safetyUnsafe
capabilities["Basic"]

ValueCurve:GetKeys

Returns a copy of all the keys in the ValueCurve as a Luau array of ValueCurveKeys.

Returns

TypeDescription
ArrayArray of ValueCurveKeys.
FieldValue
securityNone
thread safetyUnsafe
capabilities["Basic"]

ValueCurve:GetValueAtTime

Samples the value curve at a given time passed as argument.

Parameters

NameTypeDefaultDescription
timefloatTime at which to sample the curve.

Returns

TypeDescription
Variant?Value of the curve at the requested time.
FieldValue
securityNone
thread safetyUnsafe
capabilities["Basic"]

ValueCurve:InsertKey

Adds the key passed as an argument to this curve. If a key at the same time is found, it will be replaced. In the returned array, the first value is true if a key was added or false if a previous key was replaced; the second value is the index at which the marker was added.

If there are not yet any keys, then the key may be added. If keys exist, the type of the value must match those of existing keys; otherwise a message is printed and {false, -1} is returned.

Parameters

NameTypeDefaultDescription
keyValueCurveKeyValueCurveKey to insert.

Returns

TypeDescription
Array(see description)
FieldValue
securityNone
thread safetyUnsafe
capabilities["Basic"]

ValueCurve:InsertKeyValue

Creates a ValueCurveKey from the given arguments and inserts it in this curve. If a key at the same time is found, it will be replaced. In the returned array, the first value is true if a key was added or false if a previous key was replaced; the second value is the index at which the marker was added.

If there are not yet any keys, then the key may be added. If keys exist, the type of the value must match those of existing keys; otherwise a message is printed and {false, -1} is returned.

Parameters

NameTypeDefaultDescription
timefloatTime at which to insert the new ValueCurveKey. - type: number
valueVariantValue of the inserted ValueCurveKey. - type: any
InterpolationKeyInterpolationModeInterpolation mode of the inserted ValueCurveKey. - type: KeyInterpolationMode

Returns

TypeDescription
Array(see description)
FieldValue
securityNone
thread safetyUnsafe
capabilities["Basic"]

ValueCurve:RemoveKeyAtIndex

Removes a given number (count) of keys starting from the startingIndex index and returns the number of keys that were removed.

Parameters

NameTypeDefaultDescription
startingIndexintStarting index from which to remove keys.
countint1Number of keys to remove.

Returns

TypeDescription
intNumber of keys removed.
FieldValue
securityNone
thread safetyUnsafe
capabilities["Basic"]

ValueCurve:SetKeys

Resets this curve's keys using the ValueCurveKey array passed as an argument. Keys in the keys array are sorted in ascending time order before insertion, and keys at duplicated times are removed in a stable manner.

Returns the number of keys actually inserted. Keys previously stored in this curve are removed before the keys passed as arguments are added.

The keys must all contain values of the same type. And that type must match any existing keys. Otherwise a message is printed, the keys are not added, and 0 is returned.

Parameters

NameTypeDefaultDescription
keysArrayArray of ValueCurveKeys.

Returns

TypeDescription
intNumber of keys inserted.
FieldValue
securityNone
thread safetyUnsafe
capabilities["Basic"]

Events

Inherited from Instance

NameType / ReturnsDescription
Instance.AncestryChangedFires when the Instance.Parent property of this object or one of its ancestors is changed.
Instance.AttributeChangedFires whenever an attribute is changed on the Instance.
Instance.ChildAddedFires after an object is parented to this Instance.
Instance.childAdded
Instance.ChildRemovedFires after a child is removed from this Instance.
Instance.DescendantAddedFires after a descendant is added to the Instance.
Instance.DescendantRemovingFires immediately before a descendant of the Instance is removed.
Instance.DestroyingFires immediately before (or is deferred until after) the instance is destroyed via Instance:Destroy().
Instance.StyledPropertiesChangedFires whenever any style property is changed on the instance, including when a property is set to nil.

Inherited from Object

NameType / ReturnsDescription
Object.ChangedFires immediately after a property of the object changes, with some limitations.