Help me understanding Basic Game Design Please?

Archived Forums Questions & Answers
1

Hello. i've done ton's of posts, and my First Little space invaders like game, was built 90% of the code given here. i just find things hard to grasp at the moment, and need somethings explained out for me.

How would i go about making a conveyor belt, which is Interactive with EVERY object in my scene. i have made a conveyor belt before, but all it was, was that the actual object moving along the belt, moved in a animation, which was set to Play when instantiated. this can't be the way of Doing thing, surely? do i have to create an animation, for EVERY object? can't i just use physic's? (i tried before, but all the objects i tried just slide over the belt's surface )

Any answers are EXTREMELY appreciated (No seriously, they are)

3

A conveyor belt can be done in a number of ways, but the general approach is:

  1. Decide if something is on the conveyor.
  2. Move everything on the conveyor.

A simple way to do this would be something assuming collisions are setup attached to your conveyor like:

KinematicConveyor.js (attached to every conveyor)

var speed : float = 5.0; //conveyor speed

function OnCollisionStay(collisionInfo : Collision) { //On the conveyor
    collisionInfo.transform.position += transform.forward * speed; //move stuff
}

or

PhysicsConveyor.js (attached to every conveyor)

var speed : float = 500; //conveyor force

function OnCollisionStay(collisionInfo : Collision) { //On the conveyor
    collisionInfo.rigidbody.AddForce(transform.forward * speed); //move stuff
}

If you don't have or want collisions set up, then you will have to somehow determine if you are on a conveyor and apply changes via the kinematic method. The implementation is dependent on how you choose to decide what is on a conveyor.

Conveyor.js (attached to every conveyor)

var speed : float 5.0; //conveyor speed
var objects : Array = new Array(); //everything on the conveyor

function LateUpdate() {
    for(var object : Transform in objects) {
        object.position += transform.forward * speed; //move stuff
    }
}

Conveyable.js (attached to every conveyable object)

static var conveyors : GameObject; //all the conveyors
var currentConveyor : Transform; //the current conveyor

function Start() { //Get all the conveyors once
    if(!conveyors) conveyors = GameObject.FindGameObjectsWithTag("Conveyor");
}

function Update() {
    if(currentConveyor && !CheckConveyor(currentConveyor)) { left conveyor
        var script : Conveyor = conveyor.GetComponent(Conveyor);
        for(var i : int = 0; i < script.objects.length; i++) {
            if(script.objects *== transform){*
 *script.objects.RemoveAt(i);*
 *break;*
 *}*
 *}*
 *}*
 *if(!currentConveyor) {*
 *for(var conveyor : GameObject in conveyors) {*
 *if(CheckConveyor(conveyor.transform)) { //on conveyor*
 *currentConveyor = conveyor.transform;*
 *var script : Conveyor = conveyor.GetComponent(Conveyor);*
 *script.objects.Push(transform);*
 *break;*
 *}*
 *}*
 *}*
*}*
*//Checks if on a conveyor*
*function CheckConveyor(conveyor : Transform) : boolean {*
 *return transform.position.y - conveyor.position.y + conveyor.scale.y / 2.0*
 *< 0.01 &&* 
 *transform.position.x*
 *> conveyor.position.x - conveyor.localScale.x/2.0 &&*
 *transform.position.x*
 *< conveyor.position.x + conveyor.localScale.x / 2.0 &&* 
 *transform.position.z*
 *> conveyor.position.z - conveyor.localScale.z / 2.0 &&* 
 *transform.position.z*
 *< conveyor.position.z +  conveyor.localScale.z / 2.0;*
*}*
*```*
2

Hey Nathaniel,

I would love to help you... I'm not an expert in Unity, but I have been using it for a while, and I might be able to help... I know generally how to script, make 2d models/UI's, Storyboard, and Level Design... I'll, basically, help you get your "foot in Unity's door"... Per say... Anyway, if you want you can contact me from my website (Under the Contact page: Either E-Mail, Twitter, Shout Box, Skype... Whatever you prefer...) and I'll try to answer some/all of your question...

-Hope I can help

-Gibson