Using a single square sprite to create tetris-like objects

Question

I'm currently working on a project in XNA, Visual Studio, where it is crucial I can create the classic tetris figures solely based on one square sprite (So I can return to each individual square at a later point, as I need individual squares highlighted at another point in the game).

I tried loading my square into my code, then use a matrix(Texture2D 2d-array) to draw one of my pieces:

centerPiece = new Texture2D[,] { { null, Content.Load<Texture2D>("square"), null }, { Content.Load<Texture2D>("square"), Content.Load<Texture2D>("square"), Content.Load<Texture2D>("square") }, { null, Content.Load<Texture2D>("square"), null } };

At first glance it seemed fine, but when I try to actually draw it using this method:

spriteBatch.Draw(centerPiece[,], screenView(), null, Color.White, 0f, IMGCenter(), 1f, SpriteEffects.None, 0f);

It can't draw it as an 2D array, or normal array for that matter. Neither is it able to draw the "nulls" I use in my first method, which also denies me of drawing it by the use of a nested for loop.

Am I completely on the wrong track, or am I just missing a slight detail?

Answer 1

Couple of things.

First and foremost you should only load your texture once like this:

Texture2D squareTex = Content.Load<Texture2D>("square");

And then you pass it into your array. There is no reason for the texture to occupy any more memory than that.

Secondly, no spritebatch does not take an array of textures - it takes a single one. So in your case you would loop over centerPiece like so:

foreach(Texture2D t in centerPiece) { 
    spriteBatch.draw(t, ...);
 }

Now, if you want to improve on this and save some memory you wouldn't store a bunch of textures but maybe an array of booleans instead and on every loop where the boolean is true you draw a texture. This would change the code to something like:

bool[,] shape = new boolean[,] {false, true, false, .....}
Texture2D tex = Content.Load<Texture2D>("square");

...

foreach(bool b in shape) {
    if(b) {
      spriteBatch.draw(tex, ...);
    }
}