Need advice on instantiating a percentage of gameobjects

Scripting
1

Hi,

This is doing my head in but I’d like to know if there’s a better way of doing this. I have 4 types of gameobjects[ ] in an array. I have ‘n’ total numbers of that gameobjects. I’d like to instantiate a “percentage” of those game objects e.g. 25% of n gameobjects. If n objects is 100, then 25 gameobjects should be instantiated. The position and rotation are Random.Range. Here’s my idea.

If using fixed method.

function Start() {
for(var n : int = 0; n<=25, i++) {
//Instantiate GameObject[0];
//Instantiate GameObject[1];
…etc
}
}

If using a percentage method
for(var n : int = 0; n<=(0.25 * numObjects ), i++) {
//Instantiate GameObject[0];
//Instantiate GameObject[1];
…etc
}

The methods works but it feels like it’s badly written. I’d like to know if there’s a better method of using percentages when instantiating objects. Also, in the case scenario if i’d like to give priority to instantiate an object, e.g. 50%, 20%, 20%, 10% or gameobjects, how should i set the range?

Hope that makes sense.

Appreciate the help.

2

Why not find the percentage before your for statement? Also, can you have an ‘n’ and an ‘I’ in the same line of a for()?

Anyhow, I would do this.

n = someValue/lenghtOfArray;

for(var t : int; t < n; t++)
{}

This way you set the value of the percentage first. Just base it off of the length of the array, under some value.

3

Thanks Renman3000. If getting a percentage for one value, i think it’s fine. But here’s a scenario I’m having: If i want to have 100 units of gameobjects[ ], let’s say they’re enemies. I have 4 types of enemies which i put them in an array enemies[0], enemies[1] and so on. If i want 50% of the total to be enemies[0], 20% to be enemies[1], 20% to be enemies[2], and 10% to be enemies[3]. How do set the conditions for the range? or should i just make 4 different for loops for each percentage?

4

A little something I cooked up that might help you.
It creates a mob based on a percentage composition of an Inspector set available enemy type prefabs array.

To use, drop it on a GameObject that you want to represent a group of enemies. Configure the enemyTypes array to point to your source gameobject and / or prefabs. For testing I just linked to some locally created scene objects: cube,sphere,cylinder,capsule but you would use your own models and prefabs of course.

The mob is created by filling two small arrays one of desired enemy types and the other a corresponding amount of percentages. This script doesn’t do anything to enforce or test to see if you specify percentages that are greater than 100%, or that the index of arrays that are being passed in actually are within the bounds of the enemyTypes source array. I leave that up to you.

The initial conditions are in the Start function comments.
Good luck.

#pragma strict
public var enemyTypes : GameObject[];	//Inspector filled array of enemy prefabs.

public var enemyTeam : GameObject[]; 	//Storage for the newly created enemy group

function Start () 
{
//This is the manual configuration of a mob of 100 whose composition is 
//30% cubes, 25% speres, 45% capsules
//assuming enemyTypes[0] = cube_prefab object linked in inspector
//assuming enemyTypes[1] = sphere_prefab object linked in inspector
//assuming enemyTypes[2] = cylinder_prefab object linked in inspector
//assuming enemyTypes[3] = capsule_prefab object linked in inspector


var types : int[]=new int[3];
types[0]=0;//map array percentage 0 to prefab in enemyTypes element 0
types[1]=1;//map array percentage 1 to prefab in enemyTypes element 1
types[2]=3;//map array percentage 3 to prefab in enemyTypes element 3

var spread : float[]=new float[3];
spread[0]=30.0f;//30 percent of type 0 units... 
spread[1]=25.0f;//25 percent of type 1 units... 
spread[2]=45.00;//45 percent of type 2 units...

CreateEnemyMob(100, types, spread);
ShowMobCompostionToDebug();
}

function CreateEnemyMob(mobsize : int, unitTypes : int[], unitSpread:float[])
{
//need to add some checks here.. we're passing in two raw arrays that have to match in size
//and be valid references into the enemyTypes array 

var totalSpreads : int = unitSpread.Length;
var totalTypes : int = unitTypes.Length;

if(totalSpreads != totalTypes)
	{
	//The number of passed in percentages doesn't equal the number of different unitTypes provided
	//can't assign a fixed percentage to the unitstypes provided.
	
	//this would represent bad input and should be dealt with.
	Debug.Log("The number of passed in percentages does not match the number of unit types passed");
	return;
	
	}
	
//reinitialize the enemyTeam to mach the new mob size
enemyTeam = new GameObject[mobsize];
	
var currentSpread : int = 0;
var percentCutoff : float = unitSpread[currentSpread];


var currentUnit : int = 0;
var percentStep : float = 100.0f / mobsize; //each step will be 100% / mobsize 
for(var currentPercent : float = 0.0f; currentPercent < 100.0f; currentPercent += percentStep)
	{
	if(currentPercent>=percentCutoff)
		{
		currentSpread++;
		
		percentCutoff += unitSpread[currentSpread];		
		}
	enemyTeam[currentUnit]=enemyTypes[currentSpread];	
	currentUnit++;	
	}
}

function ShowMobCompostionToDebug()
{
var mobSize : int = enemyTeam.Length;
for (var mobUnitCounter = 0; mobUnitCounter < mobSize; mobUnitCounter++)
	{
	Debug.Log("Unit #"+mobUnitCounter+" is a:"+enemyTeam[mobUnitCounter].name);	
	}
}