HPL2/HPL2 Helper Scripts/Lists

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This page documents "HelperScripts_Lists.hps" - part of HPL2/HPL2 Helper Scripts, a modder-made package of .hps files by Aetheric Games, containing script classes and functions that may be useful to HPL2 modders and custom story creators. See the main page for more information, including set-up instructions.


Summary

The script file "HelperScripts_Lists.hps" adds support for linked list classes. For beginners or other people not familiar with classes, these are best thought of as new variable types. A linked list, or just "list", is a type of collection that works similarly to an array. Both lists and arrays are ways of grouping multiple variables together under one name.

There are three main advantages to using lists over arrays. The first is that it is more efficient (and more performant) to insert, remove or re-order items in the list than it would be with an array. The second is that lists can also take up less memory than arrays. The memory requirement of an array is defined by its maximum capacity, whereas the memory requirement of a list is only as much as its current content. And therefore the third advantage is that it is not necessary to know in advance how big a list needs to be - it expands automatically as items are added. (And of course, advanced users may note that there are exceptions when an array would be more efficient, but most users won't need to worry about this.)


The basics

Declare a list like any other variable, then use the methods below to work with it. For example: 

cListInt myList;		// Declares a new cListInt, called myList, ready to collect integers.
myList.Add(68);			// Appends the first integer (68) to the list at index 0.
myList.Add(419);		// Appends the second integer (419) to the list at index 1.
myList.Get(0);			// Retrieves the integer at index 0.
myList.Set(1, 99);		// Overwrites the integer at index 1.


Indices

Like arrays, you can get the items in the list using an index operator, e.g. myList[0], myList[22], myList[LastIndex]. And like arrays, the index number is zero based. In a list or array of ten items, the first index is 0 and the last index is 9.

Getting an item from a list by its index is equivalent to using the Get() method. However, unlike arrays, this is read-only. For example: 

cListString myToDoList;
myToDoList.Add("Paint the lines.");
myToDoList.Add("Cut the man.");

string myStringZero = myToDoList.Get(0);		// OK
string myStringOne = myToDoList[1];				// OK

myToDoList.Set(0, "Paint over the lines.");		// OK
myToDoList[1] = "Cut the cheese.";				// Not OK

(This seems to be because the version of AngelScript used in HPL2 seems to only allow the index operator to get and not set. If I'm wrong and you can make this work, let me know!)


Advanced info

"HelperScripts_Lists.hps" also defines cListNodeBase and several derived node classes for each type of list. The list classes all inherit from the base class cListBase, which defines some shared functionality and handles anything that doesn't depend on the type of the stored data.

Additionally, cListGeneric is an extra list class intended for advanced users. It extends the cListBase class without defining an inner data type, to help with making custom node classes derived from cListNodeBase. Advanced users attempting this may find it helpful to take a look at the cListBase and cListGeneric definition, and to read up on how AngelScript uses object handles. Examples can be found in most of the features scripts, e.g. "HelperScripts_Slimer.hps", which implements multiple custom node classes and nested lists.


List classes

Available list classes: cListInt, cListFloat, cListDouble, cListBool, cListString, cListVector, cListPoint, cListRotator

The "List classes" section refers to all the list types unless otherwise stated.


Behaviours

Lists can be declared in the same way as other variables: 

cListFloat listOfFloats;					// Declares a list of floats.
cListString listOfStrings;					// Declares a list of strings.

myListOfFloats.Add(0.001f);					// Calling a method of the referred list.
int numStrings = myListOfStrings.Count;		// Accessing a property of the referred list.


Constructor with capacity

cListBase(uint aulMaxSize)

If the list is initialised with a constructor, then a maximum capacity can be specified for the list.
If the list is declared without a specific capacity, then the default maximum capacity is assigned, which is 65535 (or 2^16 - 1). 

// Example:
cListFloat listOfFloatsDefault;
cListVector listOfVectorsDefault;

cListFloat listOfUpToFiveFloats = cListFloat(5);
cListVector listOfUpTo1000Vectors = cListVector(1000);

The default 65535 (2^16-1) is the maximum capacity that can be indexed. Using this a or smaller arbitrary limit can help to catch runaway bugs. Advanced users may try changing the value of mulCountMax to use a smaller default maximum. Using a larger maximum will likely cause problems.
Note that arrays require as much memory as their full capacity even when empty, but lists are only ever as big as their content, so lowering the maximum size of the list does not help performance. But it might be useful in certain situations where a limit is required by design.


Constructor with data

cListBase(float[] afArray)
cListBase(cListBase aList)

Lists can be initialised with data by passing an array of values of the relevant type, or an existing list. The default capacity is used for the new list.
If the source is an array, the new list will contain copies of the array's contents. If the source is an existing list, then the new list will copy the link to the original items. Both the old and new lists will point to the same data, and changing one will change the other. To avoid this, see the Copy() method. 

// Example:
float[] myArray = { 4, 8, 15, 16, 23, 42 };
cListFloat myFirstList = cListFloat(myArray);			// Makes a new float list by copying items from the float array.
cListFloat mySecondList = myFirstList;					// Makes a new float list containing the same items as the other list.



cListFloat(float afSingleFloat)

All the derived list classes (except for cListGeneric and cListInt) can be initialised with data by passing a single value of the relevant type, to become the first item in the list. 

// Example:
cListFloat myList = cListFloat(1.2f);				// Makes a new float list with a single value.
myList.Add(2.3f);									// myList now contains: 1.2f, 2.3f


Properties

All list classes provide the following properties:


Count

uint Count

The read-only integer property Count returns the current number of items in the list. (The property Length and the method length() are provided for consistency with arrays, and are both equivalent to Count.) 

// Example 1:
cListFloat myList;
uint ulCountA = myList.Count;
myList.Add(99.99f);
uint ulCountB = myList.Count;
// ulCountA is 0. ulCountB is 1.

// Example 2:
if (listNumbers.Count < 6) listNumber.Add(42);
// The condition succeeds if the count is less than 6, and another number is added.


LastIndex

uint LastIndex

The read-only integer property LastIndex returns the last valid index, or -1 if the list is empty. 

// Example 1:
uint ulA = myListOfStrings.LastIndex;
uint ulB = myListOfStrings.Count - 1;
// ulA and ulB are equal

// Example 2:
string sLatest = myListOfStrings[myListOfStrings.LastIndex];
// sLatest becomes whatever string was added to the list most recently.


IsEmpty

bool IsEmpty

The read-only boolean property IsEmpty returns true if the list is empty, or false if not. 

// Example:
if (myList.IsEmpty) myList.Add(1);
// The condition succeeds if the list contains no items.


IsFull

bool IsFull

The read-only boolean property IsFull returns true if the list is full to its maximum capacity, or false if not. 

// Example:
if (!myList.IsFull) myList.Add(1);
// The condition succeeds if the list has space for another item.


Operators

Assignment

cListBase = cListBase

The assignment operator (equals sign "=") assigns a new set of data to the list, copied from another list. Note: the list contains handles to the data, not the data itself. So when a list is copied, both lists now refer to the same data, and any changes made to either will affect both.
If the intent is to make a duplicate of the data rather than the list handles, then the Copy() method is recommended. 

// Example:
cListString listA;
listA.Add("one");
listA.Add("two");
listA.Add("three");

cListString listB = listA;

cListString listC;
listC = listA.Copy();

listA.Set(2, "banana");

// listA and listB both lists refer to the same 3 strings, and the final content of both listA and listB is: "one", "two", "banana".
// listC was made as a copy, so it was not affected when listA[2] was changed. listC still has: "one", "two", "three".


Methods

Setting list items

cListBase and its derived classes provide the following methods for assigning items to the list:


Add()

bool Add(int alItem)
bool Add(float afItem)
bool Add(double adItem)
bool Add(bool abItem)
bool Add(string asItem)
bool Add(cVector avItem)
bool Add(cPoint avItem)
bool Add(cRotator avItem)

Creates a new item appended to the list. If the list is full or the item cannot be added, it returns false. If it was successfull appended, it returns true.

  1. int alItem, float afItem, double adItem, bool abItem, string asItem, cVector avItem, cPoint avItem, or cRotator avItem - The item, of the appropriate type, to be added.
// Example 1:
myListOfFloats.Add(1.0f);
myListOfPoints.Add(cPoint(10, 15, 20));
// The new values are appended to the list.

// Example 2:
if (!listNumbers.Add(-1.0f)) Debug.Message(1, "Error - could not add to list!");
// The condition succeeds if Add failed.


Set()

bool Set(uint aulIndex, int alItem)
bool Set(uint aulIndex, float afItem)
bool Set(uint aulIndex, double adItem)
bool Set(uint aulIndex, bool abItem)
bool Set(uint aulIndex, string asItem)
bool Set(uint aulIndex, cVector avItem)
bool Set(uint aulIndex, cPoint avItem)
bool Set(uint aulIndex, cRotator avItem)

Assigns a new value to an indexed item in the list, if it exists. If the list is shorter than the index or the item cannot be added, this returns false. If it was successfull set, it returns true.

  1. uint aulIndex - The index of the item to be changed.
  2. int alItem, float afItem, double adItem, bool abItem, string asItem, cVector avItem, cPoint avItem, or cRotator avItem - The item, of the appropriate type, to be assigned.
// Example:
myListOfBools.Set(7, false);
// The bool at index 7 in the list becomes false, replacing the previous one.


Insert()

bool Insert(uint aulIndex, int alItem)
bool Insert(uint aulIndex, float afItem)
bool Insert(uint aulIndex, double adItem)
bool Insert(uint aulIndex, bool abItem)
bool Insert(uint aulIndex, string asItem)
bool Insert(uint aulIndex, cVector avItem)
bool Insert(uint aulIndex, cPoint avItem)
bool Insert(uint aulIndex, cRotator avItem)

Inserts a new item into the list at the given index. (The item previous at that index becomes the next one.) If the given index is not a valid place to insert an item, then then return value will be false. Otherwise the item is inserted and it returns true.

  1. uint aulIndex - The index where the new item will be inserted.
  2. int alItem, float afItem, double adItem, bool abItem, string asItem, cVector avItem, cPoint avItem, or cRotator avItem - The item, of the appropriate type, to be inserted.
// Example 1:
myListOfBools.Insert(7, false);
// The bool at index 7 in the list becomes false, displacing the previous one to index 8.

// Example 2:
if (!myList.Insert(10, "hello") myList.Add("hello");
// Attempts to insert the string at index 10, and if that fails the string is appended instead.


Concatenate()

bool Concatenate(cListBase aList)
bool Concatenate(int[] alArray)
bool Concatenate(float[] afArray)
bool Concatenate(double[] adArray)
bool Concatenate(bool[] abArray)
bool Concatenate(string[] asArray)
bool Concatenate(cVector[] avArray)
bool Concatenate(cPoint[] avArray)
bool Concatenate(cRotator[] avArray)

Takes either a second list or array of the same type and appends it to this one. It first checks to make sure there is enough capacity. Returns true if items were successfully added, or false if not.
If an array is supplied, new list items are created to match them. If a list is suplied the items are not duplicated - both lists refer to the same items in memory, and changing them will change both lists.

  1. cListBase aList (or any list type), or an array of int[], float[], double[], bool[], string[], cVector[], cPoint[] or cRotator[] - The items to be added.
// Example 1:
cListFloat listOfFloatsA;
listOfFloatsA.Add(1.0f);
listOfFloatsA.Add(2.0f);

float[] arrayOfFloatsB = { 3.0f, 4.0f };
listOfFloatsA.Concatenate(arrayOfFloatsB);
// listOfFloatsA now contains 1.0f, 2.0f, 3.0f, 4.0f.

// Example 2:
cListFloat listOfFloatsA;
listOfFloatsA.Add(1.0f);
listOfFloatsA.Add(2.0f);

cListFloat listOfFloatsB;
listOfFloatsB.Add(3.0f);
listOfFloatsB.Add(4.0f);

listOfFloatsA.Concatenate(listOfFloatsB);
listOfFloatsA.Set(3, 99.9f);
// listOfFloatsA now contains 1.0f, 2.0f, 3.0f, 99.9f.
// listOfFloatsB now contains 3.0f, 99.9f.


Getting list items

cListBase and its derived classes provide the following methods for retrieving items from the list:


Get()

int Get(uint aulIndex)
float Get(uint aulIndex)
double Get(uint aulIndex)
bool Get(uint aulIndex)
string Get(uint aulIndex)
cVector Get(uint aulIndex)
cPoint Get(uint aulIndex)
cRotator Get(uint aulIndex)

Traverses the list and retrieves an item from the given index, if it exists. If the item does not exist in the list, a default value will be returned instead, e.g. -1 or an empty string.
See GetIfValid() if you want to be sure the item exists. You can also use an index operator (e.g. myList[i]) to get list items.

  1. uint aulIndex - The index of the item to be retrieved.
// Example:
cListString myToDoList;
myToDoList.Add("Paint the lines.");
myToDoList.Add("Cut the man.");

string myStringZero = myToDoList.Get(0);
string myStringLast = myToDoList.Get(myToDoList.LastIndex);
// myStringZero becomes the value from the start of the list.
// myStringLast becomes the value that happens to be at the end of the list.


GetIfValid()

bool GetIfValid(uint aulIndex, int &out alTarget)
bool GetIfValid(uint aulIndex, float &out afTarget)
bool GetIfValid(uint aulIndex, double &out adTarget)
bool GetIfValid(uint aulIndex, bool &out abTarget)
bool GetIfValid(uint aulIndex, string &out asTarget)
bool GetIfValid(uint aulIndex, cVector &out avTarget)
bool GetIfValid(uint aulIndex, cPoint &out avTarget)
bool GetIfValid(uint aulIndex, cRotator &out avTarget)

Traverses the list and retrieves an item from the given index, as long as it is valid.
The second parameter is an ouput parameter. If the item at the given index exists then the item is assigned to the Target &out parameter, and the function returns true. If the item doesn't exist in the list, the function returns false.
See Get() if you don't care about validation and just want to return the item.

  1. uint aulIndex - The index of the item to be retrieved.
  2. int alTarget, float afTarget, double adTarget, bool abTarget, string asTarget, cVector avTarget, cPoint avTarget, or cRotator avTarget - The variable, of the appropriate type, where the retrieved item will be stored.
// Example:
int retrievedInteger;
if(!myListOfInts.GetIfValid(3, retrievedInteger)) retrievedInteger = -1;
// retrievedInteger will be assigned the value retrieved from index 3 in the list, if it exists.
// If it doesn't exist, the condition will succeed and retrievedInteger with be assigned -1 instead.


GetRandom()

int GetRandom()
float GetRandom()
double GetRandom()
bool GetRandom()
string GetRandom()
cVector GetRandom()
cPoint GetRandom()
cRotator GetRandom()

Randomly selects an item from the list and returns it. If the list is empty, a default value will be returned instead, e.g. -1 or an empty string. 

// Example:
string sRandomColor = listOfColors.GetRandom();
// The string sRandomColor is assigned a random value from listOfColors.


Pop()

int Pop()
float Pop()
double Pop()
bool Pop()
string Pop()
cVector Pop()
cPoint Pop()
cRotator Pop()

Returns the last item in the list, and removes that item. If the list is empty, a default value will be returned instead, e.g. -1 or an empty string. 

// Example:
int[] myArray = { 4, 8, 15, 16, 23 };
cListInt listNumbers = cListInt(myArray);
int lA = listNumbers.Pop();
int lB = listNumbers.Pop();
int lC = listNumbers.Pop();
// lA, lB, and lC have become 23, 16, and 15. myArray now contains only 4 and 8.


PopRandom()

int PopRandom()
float PopRandom()
double PopRandom()
bool PopRandom()
string PopRandom()
cVector PopRandom()
cPoint PopRandom()
cRotator PopRandom()

Randomly selects an item from the list, returns it and them removes it. If the list is empty, a default value will be returned instead, e.g. -1 or an empty string. 

// Example:
string sRandomColor = listOfColors.GetRandom();
// The string sRandomColor is assigned a random value from listOfColors, and that value is no longer available in the list.


Copy()

cListInt Copy(cListInt aList)
cListFloat Copy(cListFloat aList)
cListDouble Copy(cListDouble aList)
cListBool Copy(cListBool aList)
cListVector Copy(cListVector aList)
cListPoint Copy(cListPoint aList)
cListRotator Copy(cListRotator aList)

Returns a new list that is a duplicate of this list. The items in the new list are new items. Changing either list will not affect the other.

  1. cListBase aList (or any list type) - The items to be added.
// Example:
cListString listA;
listA.Add("one");
listA.Add("two");
listA.Add("three");

cListString listB = listA;

cListString listC;
listC = listA.Copy();

listA.Set(2, "banana");

// listA and listB both lists refer to the same 3 strings, and the final content of both listA and listB is: "one", "two", "banana".
// listC was made as a copy, so it was not affected when listA[2] was changed. listC still has: "one", "two", "three".


Removing list items

cListBase and its derived classes provide the following methods for removing items from the list: (See also: Pop() and PopRandom())


RemoveAt()

bool RemoveAt(uint aulIndex)

Traverses the list and removes the given index. Returns true if the index was valid and was removed, or false if not.

  1. uint aulIndex - The index of the item to be removed.
// Example 1:
myList.RemoveAt(7);

// Example 2:
if (myList.RemoveAt(7)) myList.Append("something new");
// If the removal was successful, then a new value is appended.


RemoveItem()

bool RemoveItem(int alItem)
bool RemoveItem(float afItem)
bool RemoveItem(double adItem)
bool RemoveItem(bool abItem)
bool RemoveItem(string asItem)
bool RemoveItem(cVector avItem)
bool RemoveItem(cPoint avItem)
bool RemoveItem(cRotator avItem)

Searches the list for a matching item and removes the first matching item it finds. Returns true if the item was found and removed, or false if not.

  1. int alItem, float afItem, double adItem, bool abItem, string asItem, cVector avItem, cPoint avItem, or cRotator avItem - The item, of the appropriate type, to be searched for and removed.
Example 1:
myListOfBools.RemoveItem(false);
// The first instance of false in the list will be removed.

// Example 2:
int  lRemoved = 0;
int[] myArray = { 4, 8, 0, 15, 16, 0, 23, 0 };
cListInt listNumbers = cListInt(myArray);
while (listNumbers.Remove(0))
{
    lRemoved++;
	DoStuff();
}
// The Remove() call will repeat until it returns false, at which point the value of lRemoved will be 3.


RemoveAll()

bool RemoveAll(int alItem)
bool RemoveAll(float aItem)
bool RemoveAll(double aItem)
bool RemoveAll(bool aItem)
bool RemoveAll(string aItem)
bool RemoveAll(cVector aItem)
bool RemoveAll(cPoint aItem)
bool RemoveAll(cRotator aItem)

Searches the list for matching items and removes the all matching items. Returns true if any items were found and removed, or false if not.

  1. int alItem, float afItem, double adItem, bool abItem, string asItem, cVector avItem, cPoint avItem, or cRotator avItem - The item, of the appropriate type, to be searched for and removed.
// Example:
myListOfFloats.RemoveAll(0.0f);
// All the zeros will be removed from the list


Searching lists

cListBase and its derived classes provide the following methods for searching for items in the list:


Find()

int Find(int alItem)
int Find(float afItem)
int Find(double adItem)
int Find(bool abItem)
int Find(string asItem)
int Find(cVector avItem)
int Find(cPoint avItem)
int Find(cRotator avItem)

Searches the list for a matching item and returns the index of the first match. If the item is not found, -1 is returned instead.

  1. int alItem, float afItem, double adItem, bool abItem, string asItem, cVector avItem, cPoint avItem, or cRotator avItem - The item, of the appropriate type, to be searched for.
// Example:
cListInt myListOfInts;
myListOfInts.Add(11);
myListOfInts.Add(22);
myListOfInts.Add(33);

uint lIndexTwentyTwo = myListOfInts.Find(22);
uint lIndexFortyFour = myListOfInts.Find(44);
// lIndexTwentyTwo becomes 1. lIndexFortyFour becomes -1.


Contains()

bool Contains(int alItem)
bool Contains(float afItem)
bool Contains(double adItem)
bool Contains(bool abItem)
bool Contains(string asItem)
bool Contains(cVector avItem)
bool Contains(cPoint avItem)
bool Contains(cRotator avItem)

Searches the list for a matching item and returns true if found, or false if not.

  1. int alItem, float afItem, double adItem, bool abItem, string asItem, cVector avItem, cPoint avItem, or cRotator avItem - The item, of the appropriate type, to be searched for.
// Example:
cListInt myListOfInts;
myListOfInts.Add(11);
myListOfInts.Add(22);
myListOfInts.Add(33);

bool bHasTwentyTwo = myListOfInts.Find(22);
bool bHasFortyFour = myListOfInts.Find(44);
// bHasTwentyTwo becomes true. bHasFortyFour becomes false.


CountItem()

uint CountItem(int alItem)
uint CountItem(float afItem)
uint CountItem(double adItem)
uint CountItem(bool abItem)
uint CountItem(string asItem)
uint CountItem(cVector avItem)
uint CountItem(cPoint avItem)
uint CountItem(cRotator avItem)

Searches the list for matching items and returns the number of matches found.

  1. int alItem, float afItem, double adItem, bool abItem, string asItem, cVector avItem, cPoint avItem, or cRotator avItem - The item, of the appropriate type, to be searched for.
// Example:
cListString myListOfStrings;
myListOfStrings.Add("up");
myListOfStrings.Add("down");
myListOfStrings.Add("sideways");
myListOfStrings.Add("down");

int lNumDown = myListOfStrings.CountItem("down");
int lNumForward = myListOfStrings.CountItem("forward");
// lNumDown becomes 2. lNumForward becomes 0.


Numeric lists

Some of the derived list classes dealing with numeric values provide the methods for arithmetic operations across the list:


Min()

int Min()
float Min()
double Min()
bool Min()
cVector Min()
cPoint Min()

Returns the lowest value in the list. cListInt, cListFloat, cListDouble, cListBool, cListVector, and cListPoint only.
For bools, this is returns false if there is a false - like logical AND over the list. For vectors and points, this evaluates and compares each square length. 

// Example:
cListFloat fRandomList;
for (uint i = 0; i < 10; i++) fRandomList.Add(Math.RandomFloat());
float fSmallest = fRandomList.Min();
// fRandomList is assigned ten random floats, and whichever is the smallest is assigned to fSmallest.


Max()

int Max()
float Max()
double Max()
bool Max()
cVector Min()
cPoint Min()

Returns the highest value in the list. cListInt, cListFloat, cListDouble, cListBool, cListVector, and cListPoint only.
For bools, this is returns true if there is a true - like logical OR over the list. For vectors and points, this evaluates and compares each square length. 

// Example:
cListFloat fRandomList;
for (uint i = 0; i < 10; i++) fRandomList.Add(Math.RandomFloat());
float fLargest = fRandomList.Max();
// fRandomList is assigned ten random floats, and whichever is the largest is assigned to fLargest.


FindMin()

uint FindMin()

Returns the first index of the item with the lowest value in the list. cListInt, cListFloat, cListDouble, cListBool, cListVector, and cListPoint only. 

// Example:
cListFloat fRandomList;
for (uint i = 0; i < 10; i++) fRandomList.Add(Math.RandomFloat());
int lSmallest = fRandomList.FindMin();
// fRandomList is assigned ten random floats, and the index of the smallest is assigned to lSmallest.


FindMax()

uint FindMax()

Returns the first index of the item with the highest value in the list. cListInt, cListFloat, cListDouble, cListBool, cListVector, and cListPoint only. 

// Example:
cListFloat fRandomList;
for (uint i = 0; i < 10; i++) fRandomList.Add(Math.RandomFloat());
int lLargest = fRandomList.FindMax();
// fRandomList is assigned ten random floats, and the index of the largest is assigned to lLargest.


Sum()

int Sum()
float Sum()
double Sum()
bool Sum()
cVector Sum()
cPoint Sum()

Returns the total of all the items in the list, added together. cListInt, cListFloat, cListDouble, cListBool, cListVector, and cListPoint only.
For bools, this is returns true if there is a true - the same as logical OR. For vectors, this is equivalent to the combined path of each vector. 

Example 1:
int[] myArray = { 4, 8, 15, 16, 23, 42 };
cListInt listNumbers = cListInt(myArray);
int lTot = listNumbers.Sum();
// lTot becomes 108.

// Example 2:
cListPoint listGridSteps;
listGridSteps.Add(cPoint(1, 0));
listGridSteps.Add(cPoint(0, 1));
listGridSteps.Add(cPoint(0, 1));
listGridSteps.Add(cPoint(-1, 0));

cPoint vFinalPos = listGridSteps.Sum()
// This example imagines a puzzle involving steps on a grid. Each step is stored in a list of points and the final position is the sum of the list. (0,2 in this case.)


Average()

int Average()
float Average()
double Average()
bool Average()
cVector Average()
cPoint Average()

Returns the mean average of all the items in the list. cListInt, cListFloat, cListDouble, cListBool, cListVector, cListPoint only.
Note that for ints, the answer will be truncated. For bools, this basically returns true if there are more true items than false. For vectors this is like finding the "centre of balance" of some points. 

//Example 1:
int[] myArray = { 4, 8, 15, 16, 23, 42 };
cListInt listNumbers = cListInt(myArray);
int lAvg = listNumbers.Average();
// lAvg becomes 18.

// Example 2:
cListVector listGruntPos;
listGruntPos.Add(GetEntityPosVec("grunt1"));
listGruntPos.Add(GetEntityPosVec("grunt2"));
listGruntPos.Add(GetEntityPosVec("grunt3"));

SetEntityPosVec("orb", listGruntPos.Average());
// This example imagines an effect where an entity is positioned at the mid-point between 3 enemies.


Ordering lists

cListBase and its derived classes provide the following methods for ordering items in the list:


Swap()

bool Swap(uint aulA, uint aulB)

Swaps the places of two items in the array. Returns false if either of the indeces are invalid, or true if the swap went ahead.

  1. uint aulA - The index of the first item to be swapped.
  2. uint aulB - The index of the second item to be swapped.
// Example:
cListInt myListOfInts;
myListOfInts.Add(33);
myListOfInts.Add(11);
myListOfInts.Add(22);
myListOfInts.Add(44);
myListOfInts.Swap(0, 1);
myListOfInts.Swap(1, 2);
// After the two swaps, the list is in numerical order.


Sort()

void Sort(abDescending = false)

Re-orders a list of numbers, to put them in numerical order, using bubble sort. Bubble sort is simple but inefficient, so sorting large lists very frequently will have a performance impact. cListInt, cListFloat, cListDouble, cListVector, cListPoint only.
For vectors, the list will be sorted by square length.

  1. bool abDescending (optional, default = false) - If true, the items will be ordered highest-to-lowest, otherwise lowest-to-highest.
// Example:
cListInt myListOfInts;
myListOfInts.Add(33);
myListOfInts.Add(11);
myListOfInts.Add(22);
myListOfInts.Add(44);
myListOfInts.Sort();
// The list is now sorted into ascending numerical order.
myListOfInts.Sort(true);
// The list is now sorted into descending numerical order.


Shuffle()

void Shuffle()

Changes the order of the list to a new, random order. 

// Example:
cListInt myListOfInts;
for (int i = 1; i <= 10; i++) myListOfInts.Add(i);
myListOfInts.Shuffle();
// The list now contains the numbers 1 to 10, in a random order with no repetition or missing numbers.


Arrays from lists

cListBase and its derived classes provide the following methods for transforming lists into arrays:


ToArray()

int[] ToArray()
float[] ToArray()
double[] ToArray()
string[] ToArray()
cVector[] ToArray()
cPoint[] ToArray()
cRotator[] ToArray()

Makes an new array, where each element in the array is a copy of an item from the list, and returns the array.


ToStringArray()

string[] ToArray()

Makes an new array, where each element in the array is a string version of each item in the list, and returns the array. (Uses the ToString() method of each node class.)


Node classes

The node classes contain the actual items in the lists and provide ways to access the data or links between nodes. Generally, it is not recommended to work with these directly, but use the functions of the list classes instead. More advanced users can extend the cListNodeBase class, or any class, and use it with cListGeneric.

Available node classes: cListNodeInt, cListNodeFloat, cListNodeDouble, cListNodeBool, cListNodeString, cListNodeVector, cListNodePoint, cListRotator


Behaviours

In the derived node classes, the default constructor creates a node with a default item, or an argument can be provided to set the initial value. For example, in the cListNodeInt class: 

cListNodeInt() 					// Creates an int node with value 0.
cListNodeInt(int alItem)		// Creates an int node with value alItem.


Properties

All dervied node classes have one public property, named Item:


Item

int Item
float Item
double Item
bool Item
string Item
cVector Item
cPoint Item
cRotator Item

The property Item can get or set the data item in the node, using the appropriate type.


Methods

SetNext()

void SetNext(cListNodeBase@ ahNext)

Assigns a handle to the next node. To break the link, assign null or use ClearNext().

  1. cListNodeBase@ ahNext - A handle to an instance of cListNodeBase.


GetNext()

cListNodeBase@ GetNext()

Returns the handle to the next node. If there isn't one, it will return null.


ClearNext()

void ClearNext()

Returns the handle to the next node. If there isn't one, it will return null.


ToString()

string ToString()

Resets the handle to the next node to null


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