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Question Cannot load Image Texture from StreamingAssets folder

Discussion in 'Scripting' started by farazk86, May 22, 2023.

  1. farazk86

    farazk86

    Joined:
    May 31, 2017
    Posts:
    184
    Hi,

    I want to be able to change textures of a gameObject after build. I understand that I will have to do this by keeping my textures in StreamingAssets folder and change the image asset there after game has built.

    But I am not able to load the texture. After reading the documentation I am using the following code to read in the file from StreamingAssets and then convert to texture.

    Code (CSharp):
    1.  
    2.  
    3.         string basePath = Path.Combine(Application.streamingAssetsPath, "Textures");  // The images are within the Textire folder
    4.         string[] textureFiles = Directory.GetFiles(basePath).Where(file => file.ToLower().EndsWith("png") || file.ToLower().EndsWith("jpg")).ToArray();
    5.  
    6.         //Converts desired path into byte array
    7.         byte[] pngBytes = File.ReadAllBytes(textureFiles[0]);
    8.         Debug.Log(textureFiles[0]);
    9.         //Creates texture and loads byte array data to create image
    10.         Texture2D accidentDensity = new Texture2D(2, 2);
    11.         ImageConversion.LoadImage(accidentDensity, pngBytes, false);
    12.  
    Debug.Log(textureFiles[0]) gives me the full path of the image I want to use, so the file is being read.

    But when I apply the above texture using (this is in URP):

    Code (CSharp):
    1. model.GetComponent<Renderer>().material.SetTexture("_BaseMap", accidentDensity);
    It doesnt work and I get a blank material, no texture applied.

    But when I copy the image to Resources Folder and load the image using
    Code (CSharp):
    1. accidentDensity = Resources.Load<Texture2D>("Accident_denisty");
    And then apply the material using above line of code, the texture applies to the model.

    What am I doing wrong?

    Thanks
     
  2. All_American

    All_American

    Joined:
    Oct 14, 2011
    Posts:
    1,528
    Why not just have the materials already premade and just switch materials?

    Or are you importing the textures at runtime?
     
  3. farazk86

    farazk86

    Joined:
    May 31, 2017
    Posts:
    184
    I want to import textures at runtime
     
  4. All_American

    All_American

    Joined:
    Oct 14, 2011
    Posts:
    1,528
    Is there code you’re not including here? Getting files from the StreamingAssets folder isn’t importing at runtime…..they’re already there.
     
  5. Kurt-Dekker

    Kurt-Dekker

    Joined:
    Mar 16, 2013
    Posts:
    36,563
    Waaaaay way too many dots man, figure out which step is failing.

    For one, .material may give you a new Material copy back (see docs).

    For two, is _BaseMap even correct?

    If you have more than one or two dots (.) in a single statement, you're just being mean to yourself.

    How to break down hairy lines of code:

    http://plbm.com/?p=248

    Break it up, practice social distancing in your code, one thing per line please.

    "Programming is hard enough without making it harder for ourselves." - angrypenguin on Unity3D forums

    "Combining a bunch of stuff into one line always feels satisfying, but it's always a PITA to debug." - StarManta on the Unity3D forums


    Time to start debugging! Here is how you can begin your exciting new debugging adventures:

    You must find a way to get the information you need in order to reason about what the problem is.

    Once you understand what the problem is, you may begin to reason about a solution to the problem.

    What is often happening in these cases is one of the following:

    - the code you think is executing is not actually executing at all
    - the code is executing far EARLIER or LATER than you think
    - the code is executing far LESS OFTEN than you think
    - the code is executing far MORE OFTEN than you think
    - the code is executing on another GameObject than you think it is
    - you're getting an error or warning and you haven't noticed it in the console window

    To help gain more insight into your problem, I recommend liberally sprinkling
    Debug.Log()
    statements through your code to display information in realtime.

    Doing this should help you answer these types of questions:

    - is this code even running? which parts are running? how often does it run? what order does it run in?
    - what are the names of the GameObjects or Components involved?
    - what are the values of the variables involved? Are they initialized? Are the values reasonable?
    - are you meeting ALL the requirements to receive callbacks such as triggers / colliders (review the documentation)

    Knowing this information will help you reason about the behavior you are seeing.

    You can also supply a second argument to Debug.Log() and when you click the message, it will highlight the object in scene, such as
    Debug.Log("Problem!",this);


    If your problem would benefit from in-scene or in-game visualization, Debug.DrawRay() or Debug.DrawLine() can help you visualize things like rays (used in raycasting) or distances.

    You can also call Debug.Break() to pause the Editor when certain interesting pieces of code run, and then study the scene manually, looking for all the parts, where they are, what scripts are on them, etc.

    You can also call GameObject.CreatePrimitive() to emplace debug-marker-ish objects in the scene at runtime.

    You could also just display various important quantities in UI Text elements to watch them change as you play the game.

    Visit Google for how to see console output from builds. If you are running a mobile device you can also view the console output. Google for how on your particular mobile target, such as this answer or iOS: https://forum.unity.com/threads/how-to-capturing-device-logs-on-ios.529920/ or this answer for Android: https://forum.unity.com/threads/how-to-capturing-device-logs-on-android.528680/

    If you are working in VR, it might be useful to make your on onscreen log output, or integrate one from the asset store, so you can see what is happening as you operate your software.

    Another useful approach is to temporarily strip out everything besides what is necessary to prove your issue. This can simplify and isolate compounding effects of other items in your scene or prefab.

    Here's an example of putting in a laser-focused Debug.Log() and how that can save you a TON of time wallowing around speculating what might be going wrong:

    https://forum.unity.com/threads/coroutine-missing-hint-and-error.1103197/#post-7100494

    "When in doubt, print it out!(tm)" - Kurt Dekker (and many others)

    Note: the
    print()
    function is an alias for Debug.Log() provided by the MonoBehaviour class.
     
  6. farazk86

    farazk86

    Joined:
    May 31, 2017
    Posts:
    184
    Yes, that is what I am trying to do, the code I am using is to load the images from the streaming assets folder.

    @Kurt-Dekker

    Thank you for the helpful reply regarding breaking down my statement to identify the culprit and I usually take that route to identify the problem, but in this case the problem is not in the line you quoted. As when the image is loaded from the Resources folder the texture is applied correctly.

    The problem is the image is not loading from the streaming assets folder.
     
  7. farazk86

    farazk86

    Joined:
    May 31, 2017
    Posts:
    184
    So I found an answer to this here: https://stackoverflow.com/questions...mage-of-streamingassets-a-texture-of-material

    Apparently, ``DownloadHandlerTexture`` is the preferred method of loading textures from the Streaming Assets folder.

    I tried it with my code and the textures are being correctly loaded and applied.

    Posting my code and solution to this to help people coming across this in future.

    Code (CSharp):
    1.  
    2. Texture2D accidentDensity;
    3.  
    4. IEnumerator LoadTexture()
    5.     {
    6.         string basePath = Path.Combine(Application.streamingAssetsPath, "Textures");
    7.         string[] textureFiles = Directory.GetFiles(basePath).Where(file => file.ToLower().EndsWith("png") || file.ToLower().EndsWith("jpg")).ToArray();
    8.  
    9.         string url = textureFiles[2];
    10.         print(url);
    11.  
    12.         using (var uwr = UnityWebRequestTexture.GetTexture(url))
    13.         {
    14.             yield return uwr.SendWebRequest();
    15.  
    16.             if (uwr.isNetworkError || uwr.isHttpError)
    17.             {
    18.                 Debug.Log(uwr.error);
    19.             }
    20.             else
    21.             {
    22.                 // Get downloaded texture
    23.                 accidentDensity = DownloadHandlerTexture.GetContent(uwr);
    24.                 //_Material.SetTexture("_MainTex", texture);
    25.             }
    26.         }
    27.     }
     
    Last edited: May 23, 2023