将图像加载为Texture2D

Question

In my program, I want to save some screenshots and load them later on to compute somethings. I created a methode to compute the image names:

static public string generatePhotoName (string cameraName, float time)
{
    return "G:/Data/unity/cameraDemo/" + 
        DataController.measurmentPath + 
        "/photos" + "/" + 
        cameraName + "/" + 
        time.ToString () + "_" + cameraName + ".png";
}

This worked fine for saving, but when I try to load an image, File.Exists (filePath) returns false .

But when I hardcoded the filepath, loading works fine too:

static public string generatePhotoName (string cameraName, float time)
{
    return "G:/Data/unity/cameraDemo/demo/photos/Camera/test.png";
}

It even works with "real" image names(ie 3.827817_Camera.png).

Using Path.Combine(...) and changing "/" to "\\" did not change anything...

// edit: this is my load methode

static public Texture2D loadPhotoToTexture (string filePath)
{

    Texture2D tex = null;
    byte[] fileData;

    if (File.Exists (filePath)) {
        fileData = File.ReadAllBytes (filePath);
        tex = new Texture2D (2, 2);
        tex.LoadImage (fileData); //..this will auto-resize the texture dimensions.
    } else {
        Debug.Log (filePath + " does not exist");
    }
    return tex;
}`

// edit2: some more code

This is how I call the methode Texture2D photo = DataController.loadPhotoToTexture(photoData.getFileName ());

And this is my class PhotoData

public class PhotoData : BaseData
{
    private string _cameraName;

    public string cameraName {
    get { return _cameraName; }
    set { _cameraName = value; }
    }

    private float _time;

    public float time {
        get { return _time; }
        set { _time = value; }
    }

    public PhotoData ()
    {
    }

    public PhotoData (string cameraName, float time)
    {
        _cameraName = cameraName;
        _time = time;
    }

    public string getFileName ()
    {
        return PlayerController.generatePhotoName (_cameraName, _time);
    }
}

Answer 1

The problem was, that I tried to save and load the screenshots in one Update() -call.

I fixed it by changing it to right-click to take and save a screenshot and left-click to load the screenshot.

Answer 2

If you want to store images to a certain file on disk, not inside your game folder structure, do this: create a folder, and store its location (filepath). For example:

string screenshotFileName = time.ToString () + "_" + cameraName + ".png"
string screenshotDirectory;
screenshotDirectory = @"C:\someFolder\anotherFolder\";
try { Directory.CreateDirectory(directory); }
catch (Exception e)
{ //you should catch each exception separately
   if (e is DirectoryNotFoundException || e is UnauthorizedAccessException)
       Debug.LogError("OMG PANIC");
}
FileInfo filepath = new FileInfo(screenshotDirectory+screenshotFileName);
if(filepath.Exists)
{
    //load the file
}

You could also simply create a folder, with a relative path, which will be in the same folder as your executable, by changing the screenshotDirectory to screenshotDirectory = @"screenshots\\"+cameraName+@"\\";

Edit: You seem to load the texture correctly. Are you assigning it to the material's main texture? Where is your code encountering the problem? For example if you're running this script on the same object that you want the texture to be applied:

this.GetComponent<Renderer>().material.mainTexture = loadedTexture;

Also, when you want to load images, it's best that you use the Resources folder, which uses forwards slashes, not . Store everything that you might want to load on runtime there, and use Resources.Load().