Replacing Textures in Scene with Textures from a Server (C#)

Unity Engine
1

Hi all,

I’m working on this capstone project for my master’s degree. It’s a virtual reality browser. I am new to programming and need your help.

I set up an array of 44 mesh blocks with textures applied to them with a c# script. The array appears to be working properly when I start the game. I see the array in my Inspector and I can see the generated messages in the console.

using UnityEngine;
using System.Collections;

[System.Serializable]
public class Arrays : MonoBehaviour
{
    public GameObject[] meshes;
    // Use this for initialization
    void Start ()
    {
        meshes = GameObject.FindGameObjectsWithTag("quilt_block");

        for(int i = 0; i < meshes.Length; i++)
        {
            Debug.Log("quilt_block Number "+i+" is named "+meshes[i].name);}

    }
}

Everything is not ordered correctly, though. When I try editing the array, nothing happens, but that’s a separate secondary issue.

What I’ve been trying to figure out is how to replace all of the textures already in the scene with textures from a server whenever a trigger is set off. The trigger will essentially be a trip-line that the player walks through. I got the WWWclass code from the Unity doc working for one of the blocks (this was before I set up the array).

using UnityEngine;
using System.Collections;

public class GetURL : MonoBehaviour {
    public string url = "http://images.earthcam.com/ec_metros/ourcams/fridays.jpg";
    IEnumerator Start() {
        WWW www = new WWW(url);
        yield return www;
        Renderer renderer = GetComponent<Renderer>();
        renderer.material.mainTexture = www.texture;
    }
}

It pulls a new texture from the server at Start. I could apply the code to all 44 blocks manually, but I was looking for a more automatic method, since there’s a total of 5000+ images/textures that need to be loaded into the scene.

My instructor told me to use this code above. Then he said:

Ok, but what I’m confused about is the filenames for the images on the server already have padded 0s. So wouldn’t I need to do the reverse and convert a 0-padded string to an int?

And how would I add that to the GetURL script? And then apply everything to my array so that all the textures are in an ordered sequence for the player to look at?

I would appreciate any help because I’m completely lost right now. Can anyone point me in the right direction?

2

I suspect your instructor was thinking about the problem in reverse of how you seem to be. If you can refer to a mesh by index number then you just need to convert that index number to a zero padded string to get the correct image from the web server.

I think you should set up the array in unity so that an indexer can be used to iterate over the meshes in order. Perhaps try starting with a script which will cause each mesh to change colors in order, one per frame. You can worry about the zero-padding and downloading of images once you’ve got your array set up in the correct order and know how to iterate over them.

3

Thanks! I’ll try that and come back with an update.

4

Ok, I got the array set up in order. I used the “lock the Inspector and drag over” method to drag my meshes over to the array. For awhile, I couldn’t figure out why my array in the Inspector was being replaced by another array.

It turns out, all I had to do was delete the “FindGameObjectwithTag” line. Also, I removed the references to ‘meshes’ in my code. Here was it looks like now:

using System;
using System.Linq;
using UnityEngine;
using System.Collections.Generic;

[System.Serializable]
public class Arrays : MonoBehaviour
{
    public GameObject[] Quilt_Blocks;
    // Use this for initialization
    void Start ()
    {
        for(int i = 0; i < Quilt_Blocks.Length; i++)
        {
            Debug.Log ("quilt_block Number "+i+" is named "+ Quilt_Blocks.name);
        }
    }
}

Now, I just need to figure how to iterate over it. But I’m not even sure if my array can be managed. I have the script attached to a “Game Manager” object that I created. When I reassign the elements in the array at runtime, no changes take affect. Any ideas?

5

You’re basically already doing that, just not touching the individual items in the array.

for(int i = 0; i < Quilt_Blocks.Length; i++)
{
  Debug.Log ("quilt_block Number "+i+" is named "+ Quilt_Blocks.name);
}

Instead of getting Quilt_Blocks.name (not even sure what that is – most likely a compile error) you should get the name of the item in Quilt_Blocks at position i; like this:

for(int i = 0; i < Quilt_Blocks.Length; i++)
{
  Debug.Log ("quilt_block Number "+i+" is named "+ Quilt_Blocks[i].name);
}

I’m not sure what that means. You are reassigning elements at runtime? How? What “effects” are you expecting?

6

Thanks for your reply. I just checked my script in Unity and I do have the item Quilt_Blocks at position i. Not sure what happened when I posted the code here.

I tried changing my elements in the Inspector at runtime by loading a new prefab as a test to see if anything would happen. I guess I was wrong in expecting changes to take affect. What I really need is a script that that tells Unity what changes to make before I hit play. I realize now that I was only changing the assignments in the index.

So I guess what I need now is to tell Unity to change each item a different color as a test like you initially suggested. I couldn’t find a tutorial or anything in the forums that would help me do that.

Each item in my array is arranged like this: block_00, block_01, block_02, etc., and it ends with the 44th item, which is block_43.

7

Textures and rederers are a bit out of my league but I think you’ve got the iterating code down. Just look at some tutorials for changing the color of a GameObject. I think it might be as simple as:

for(int i = 0; i < Quilt_Blocks.Length; i++)
{
  var renderer = Quilt_Blocks[i].GetComponent<Renderer>();
  renderer.material.color = Color.red;
}

To get a more interesting visual effect, you could change just one block each frame.

int i = 0;
void update()
{
  var renderer = Quilt_Blocks[i%44].GetComponent<Renderer>();
  renderer.material.color = i / 44 % 2 == 0?Color.red:Color.green;
  i ++;
}