XNA new Texture2D retains old data

Question

I have an odd problem that I believe my relative lack of knowledge of the XNA framework prohibits me from fixing.

Basically I have a Texture2D reference that is set to a new instance of Texture2D. During runtime some of its pixels are set and this all works nicely as its drawn in the gameloop.

The odd thing is, if I set the reference to null, (it will only draw if not null) it as expected does not draw.

Later on, I set the reference to a new Texture2D and it starts drawing it to screen. The issue is it holds all the data of the original Texture2D object.

EDIT

Sorry I wasnt clear before.

What I have is something like this...

private Texture2D WorkingTexture {get; set; }

private void Update()
{
 if(some input)
 {
  this.WorkingTexture = null;
 }

 if(some other input)
 {
  this.WorkingTexture = new Texture2D(this.GraphicsDevice, 500, 500, true, SurfaceFormat.Color);

  this.WorkingTexture.SetData<Color>(0, new Rectangle((int)vector2.X, (int)vector2.Y, 4, 4), colors, 0, 16);

  }
}

private void Draw()
{
 if (this.WorkingTexture != null)
 {
    spritebatch.draw(this.WorkingTexture,.....);
 } 
}

SECOND EDIT

I have also set a for loop and manually set every pixel of the texture to a color after it is created. this works yet it still shows pixels as the colors i set them previously. This is very odd.

Please disregard this thread. The issue was very embarrassingly my own doing. I had some code that buffered up pixels to be changed and yes... you guessed it I wasn't clearing it and it was doing the work all over again on the new texture instance.

very embarrassed....

score 1 · Answer 1 · answered Jul 27 '11 at 15:14

Without having much detail to go on, it sounds like you are trying to load the Texture2D with the changes that you made earlier. Since you set it to null, when you reload the Texture2D, it will be back to the original. You'll need to save the changes you make to the pixels for later use if you want to use it again. Hope this helps!

score 1 · Answer 2 · answered Jul 27 '11 at 15:25

So you've set up a texture like this

Texture2D texture = Content.Load<Texture2D>("texture_name");

and then you apply a new reference it like so

texture = Content.Load<Texture2D>("other_texture_name");

right?

Thats not how it's supposed to be. You have to set up your GraphicsDevice to use a specific Texture. With the BasicEffect class, this would be something like this:

BasicEffect effect = new BasicEffect(GraphicsDevice);
effect.Texture = texture;
effect.CurrentTechnique.Passes[0].Apply();

hi sorry for the mixup, Ive updated the question with sample code. — Nick, Jul 27 '11 at 19:44

score 1 · Answer 3 · answered Jul 27 '11 at 16:10

How do you create the textures? If you load them from a resource (texture = Content.Load("texture_name")) the problem you describe sounds like a bug in your logic: your program is not doing what you think it's doing. Trace, debug...

If you're creating brand new textures (texture = new Texture2D(...)) it's possible (not verified) that the new texture is not initialized and its memory space is being retrieved from some kind of memory pool, so retrieving the recently marked to dispose texture data. Try to initialize your texture data as soon as you create it setting it to all-black, for example.

thanks, yes I tried filling the texture with a colour but it makes no difference, its like once you have a texture in there, it will always draw whenever I draw that reference, regardless of what instance of Texture2D is hooked up to it. — Nick, Jul 27 '11 at 20:10

XNA new Texture2D retains old data

3 Answers3