Depth buffers for different screens in XNA

Question

I don't quite understand how to handle ZBuffering for different screens in my program. I have a screenControllers class that calls a Draw method for each of my active Screen classes. The spriteBatch.Begin and spriteBatch.End calls are made in the screenController's Draw. The Screen's Draw just has a spriteBatch.Draw statement for each of the textures being drawn. I understand that I can specify depth when calling the

public void Draw (
     Texture2D texture,
     Rectangle destinationRectangle,
     Nullable<Rectangle> sourceRectangle,
     Color color,
     float rotation,
     Vector2 origin,
     SpriteEffects effects,
     float layerDepth
) 

method for spriteBatch.

But say I open one screen with textures at some given depth. Then, the second screen I open should have other textures at the same depth values as the previous but drawn in order on TOP of the previous screen. I doubt I will need this functionality because the second screen I open will probably be an options screen on top of my scene window with everything in front or it may be a portion of an interface that is not on top of the scene window but to the side. I am just wondering if this layered functionality for multiple screens can be implemented in XNA?

Answer 1

If you use different SpriteBatch to manage them I don't think you will have this kind of problem.

If you use the same SpriteBatch you could use a scaleFactor and an offsetValue to manage the layerDepth value of your Draws, in order to create different invervals for every sceen's screenDepth parameter.

I mean that if you have 2 screen the first's textures are drawn in the [0, 0.5) interval, the second one in [0.5, 1). If you have 3 of them the interval will be every 0.33 and so on...

The scaleFactor will be 1 / numberOfScreens of course.