Resize Texture2D comes out grey

Questions & Answers
1

I’m trying to resize a downloaded image but all resized images come out solid grey. Can someone please explain why?

	public void AddPhotosToList(WWW www)
       {		
        Texture2D uploadedPhoto = www.texture;
        uploadedPhoto.Resize(256,256);
        uploadedPhoto.Apply();
        memberPhotos.Add(uploadedPhoto);
        SavePhotosToCache(uploadedPhoto);	
       }

Also, I’d rather crop the texture within the boundary of 256,256. But I cant find any functions in the documentation. If anyone has any insights on that as well.

2

As the docs say about Resize: “After resizing, texture pixels will be undefined.” It just resizes the texture, it does not scale the contents. You can use this instead.

3

Regarding Eric5h5’s famous and awesome TextureScale, here’s some example code that shows a use of it, and indeed how to crop.

For google: in Unity3D take a photo from your iPhone or Android webcam device camera, take a photo on to a WebCamTexture and then scale and crop the image and save to disk.

It’s all a piece of cake with TextureScale !!

public WebCamTexture wct;

public void UserClickedTakePhoto()
	{
	// take the photo. scale down to 256
	// and crop to a central-square
	
	// !!NOTE!! for simplicity this demo code
	// assumes the tetxture is wider than high!
	
	//consider... yield return new WaitForEndOfFrame(); 
	Debug.Log("is " +wct.width +" h" +wct.height );
	
	int oldW = wct.width;	// assume it's wider than high
	int oldH = wct.height;
	
	Texture2D photo = new Texture2D(oldW, oldH,
	      TextureFormat.ARGB32, false);
	
	photo.SetPixels( 0,0,oldW,oldH, wct.GetPixels() );
	photo.Apply();
	
	Debug.Log("took photo !");
	Debug.Log("is " +photo.width +" h" +photo.height );
	
	int newH = 256;
	int newW = Mathf.FloorToInt(
	       ((float)newH/(float)oldH) * oldW );
	TextureScale.Bilinear(photo, newW,newH);
	
	Debug.Log("scaled !");
	Debug.Log("is " +photo.width +" h" +photo.height );
	
	// finally crop to central square 256.256
	int startAcross = (newW - 256)/2;
	Debug.Log("starting across at: " +startAcross);
	
	Color[] pix = photo.GetPixels(startAcross,0, 256,256);
	photo = new Texture2D(256,256, TextureFormat.ARGB32, false);
	photo.SetPixels(pix);
	photo.Apply();
	
	Debug.Log("'SetPixels' cropped !");
	Debug.Log("is " +photo.width +" h" +photo.height );
	demoImage.texture = photo;
	
	// consider
	// System.IO.File.WriteAllBytes(
	//   Application.persistentDataPath+"p.png",
	//   photo.EncodeToPNG());
	// or
	// byte[] bytes = photo.EncodeToPNG();
	// File.WriteAllBytes(
	//   Application.persistentDataPath+"p.png", bytes);
	}

Year in and year out, TextureScale is still the best and only way to scale your PNG and Texture2D in Unity3D! Hope it saves someone some typing.