Array Functions

The UUDCoreArrayFunctionLibrary provides utilities for array navigation and manipulation, with support for looping behavior.

Array_NextIndex

Returns the next index in an array, with optional looping.

When the current index is the last element:

If bLoop is true, returns 0 (wraps to beginning)
If bLoop is false, returns the last valid index

Array_NextIndex

TArray<int32> MyArray = { 0, 1, 2, 3 };
int32 CurrentIndex = 2;
bool bLoop = true;

int32 NextIndex = UUDCoreArrayFunctionLibrary::Array_NextIndex(MyArray, CurrentIndex, bLoop);
// Result: 3

// At the last element with looping:
CurrentIndex = 3;
NextIndex = UUDCoreArrayFunctionLibrary::Array_NextIndex(MyArray, CurrentIndex, bLoop);
// Result: 0 (loops back)

Parameters

Name	Type	Description
`TargetArray`	`TArray<T>`	The array to navigate
`Index`	`int32`	The current index
`bLoop`	`bool`	If `true`, wrap to beginning when at end

Returns

Name	Type	Description
`ReturnValue`	`int32`	The next index

Array_PreviousIndex

Returns the previous index in an array, with optional looping.

When the current index is 0:

If bLoop is true, returns the last valid index (wraps to end)
If bLoop is false, returns 0

Array_PreviousIndex

TArray<int32> MyArray = { 0, 1, 2, 3 };
int32 CurrentIndex = 1;
bool bLoop = true;

int32 PrevIndex = UUDCoreArrayFunctionLibrary::Array_PreviousIndex(MyArray, CurrentIndex, bLoop);
// Result: 0

// At the first element with looping:
CurrentIndex = 0;
PrevIndex = UUDCoreArrayFunctionLibrary::Array_PreviousIndex(MyArray, CurrentIndex, bLoop);
// Result: 3 (loops to end)

Parameters

Name	Type	Description
`TargetArray`	`TArray<T>`	The array to navigate
`Index`	`int32`	The current index
`bLoop`	`bool`	If `true`, wrap to end when at beginning

Returns

Name	Type	Description
`ReturnValue`	`int32`	The previous index

Use Cases

// Player presses "Next"
CurrentSelection = UUDCoreArrayFunctionLibrary::Array_NextIndex(MenuOptions, CurrentSelection, true);

// Player presses "Previous"
CurrentSelection = UUDCoreArrayFunctionLibrary::Array_PreviousIndex(MenuOptions, CurrentSelection, true);

// Next track (loop when at end)
CurrentTrack = UUDCoreArrayFunctionLibrary::Array_NextIndex(Playlist, CurrentTrack, true);

// Previous track (loop when at beginning)
CurrentTrack = UUDCoreArrayFunctionLibrary::Array_PreviousIndex(Playlist, CurrentTrack, true);

Non-Looping Selection

// Navigate without looping (useful for lists with a clear beginning/end)
CurrentIndex = UUDCoreArrayFunctionLibrary::Array_NextIndex(Items, CurrentIndex, false);
// At the last element, this returns the last index instead of looping

These functions work with any array type in Blueprints and are templated in C++ for type safety.

Summary

Function	Description
`Array_NextIndex`	Get the next index with optional looping
`Array_PreviousIndex`	Get the previous index with optional looping

Array Functions

Index Navigation

Array_NextIndex

Array_PreviousIndex

Use Cases

Cycling Through Menu Options

Playlist Navigation

Non-Looping Selection

Summary

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