So I am following this tutorial on how to draw a cube in XNA and I ran into a problem. Ok so my shader can only have texture right? I need to have a texture on the front and back of my cube. So I thought I could just have both textures stored in one texture. Problem is I do not know how to map out my UV coords to do so. (I tried dividing by 2 and such with no luck...). I am really new to this (not programming, just game development and some concepts), but how could I get UV coordinates for both halfs of the texture.

  private void ConstructCube(Vector3 Position,Vector3 Size)
    {
         _vertices = new VertexPositionNormalTexture[50];

        // Calculate the position of the vertices on the top face.
        Vector3 topLeftFront = Position + new Vector3(-1.0f, 1.0f, -1.0f) * Size;
        Vector3 topLeftBack = Position + new Vector3(-1.0f, 1.0f, 1.0f) * Size;
        Vector3 topRightFront = Position + new Vector3(1.0f, 1.0f, -1.0f) * Size;
        Vector3 topRightBack = Position + new Vector3(1.0f, 1.0f, 1.0f) * Size;

        // Calculate the position of the vertices on the bottom face.
        Vector3 btmLeftFront = Position + new Vector3(-1.0f, -1.0f, -1.0f) * Size;
        Vector3 btmLeftBack = Position + new Vector3(-1.0f, -1.0f, 1.0f) * Size;
        Vector3 btmRightFront = Position + new Vector3(1.0f, -1.0f, -1.0f) * Size;
        Vector3 btmRightBack = Position + new Vector3(1.0f, -1.0f, 1.0f) * Size;

        // Normal vectors for each face (needed for lighting / display)
        Vector3 normalFront = new Vector3(0.0f, 0.0f, 1.0f) * Size;
        Vector3 normalBack = new Vector3(0.0f, 0.0f, -1.0f) * Size;
        Vector3 normalTop = new Vector3(0.0f, 1.0f, 0.0f) * Size;
        Vector3 normalBottom = new Vector3(0.0f, -1.0f, 0.0f) * Size;
        Vector3 normalLeft = new Vector3(-1.0f, 0.0f, 0.0f) * Size;
        Vector3 normalRight = new Vector3(1.0f, 0.0f, 0.0f) * Size;

        // UV texture coordinates
        Vector2 textureTopLeft = new Vector2(1.0f * Size.X, 0.0f * Size.Y);
        Vector2 textureTopRight = new Vector2(0.0f * Size.X, 0.0f * Size.Y);
        Vector2 textureBottomLeft = new Vector2(1.0f * Size.X, 1.0f * Size.Y);
        Vector2 textureBottomRight = new Vector2(0.0f * Size.X, 1.0f * Size.Y);

        // Add the vertices for the FRONT face.
        _vertices[0] = new VertexPositionNormalTexture(topLeftFront, normalFront, textureTopLeft);
        _vertices[1] = new VertexPositionNormalTexture(btmLeftFront, normalFront, textureBottomLeft);
        _vertices[2] = new VertexPositionNormalTexture(topRightFront, normalFront, textureTopRight);
        _vertices[3] = new VertexPositionNormalTexture(btmLeftFront, normalFront, textureBottomLeft);
        _vertices[4] = new VertexPositionNormalTexture(btmRightFront, normalFront, textureBottomRight);
        _vertices[5] = new VertexPositionNormalTexture(topRightFront, normalFront, textureTopRight);

        // Add the vertices for the BACK face.
        _vertices[6] = new VertexPositionNormalTexture(topLeftBack, normalBack, textureTopRight);
        _vertices[7] = new VertexPositionNormalTexture(topRightBack, normalBack, textureTopLeft);
        _vertices[8] = new VertexPositionNormalTexture(btmLeftBack, normalBack, textureBottomRight);
        _vertices[9] = new VertexPositionNormalTexture(btmLeftBack, normalBack, textureBottomRight);
        _vertices[10] = new VertexPositionNormalTexture(topRightBack, normalBack, textureTopLeft);
        _vertices[11] = new VertexPositionNormalTexture(btmRightBack, normalBack, textureBottomLeft);

        // Add the vertices for the TOP face.
        _vertices[12] = new VertexPositionNormalTexture(topLeftFront, normalTop, textureBottomLeft);
        _vertices[13] = new VertexPositionNormalTexture(topRightBack, normalTop, textureTopRight);
        _vertices[14] = new VertexPositionNormalTexture(topLeftBack, normalTop, textureTopLeft);
        _vertices[15] = new VertexPositionNormalTexture(topLeftFront, normalTop, textureBottomLeft);
        _vertices[16] = new VertexPositionNormalTexture(topRightFront, normalTop, textureBottomRight);
        _vertices[17] = new VertexPositionNormalTexture(topRightBack, normalTop, textureTopRight);

        // Add the vertices for the BOTTOM face. 
        _vertices[18] = new VertexPositionNormalTexture(btmLeftFront, normalBottom, textureTopLeft);
        _vertices[19] = new VertexPositionNormalTexture(btmLeftBack, normalBottom, textureBottomLeft);
        _vertices[20] = new VertexPositionNormalTexture(btmRightBack, normalBottom, textureBottomRight);
        _vertices[21] = new VertexPositionNormalTexture(btmLeftFront, normalBottom, textureTopLeft);
        _vertices[22] = new VertexPositionNormalTexture(btmRightBack, normalBottom, textureBottomRight);
        _vertices[23] = new VertexPositionNormalTexture(btmRightFront, normalBottom, textureTopRight);

        // Add the vertices for the LEFT face.
        _vertices[24] = new VertexPositionNormalTexture(topLeftFront, normalLeft, textureTopRight);
        _vertices[25] = new VertexPositionNormalTexture(btmLeftBack, normalLeft, textureBottomLeft );
        _vertices[26] = new VertexPositionNormalTexture(btmLeftFront, normalLeft, textureBottomRight );
        _vertices[27] = new VertexPositionNormalTexture(topLeftBack, normalLeft, textureTopLeft);
        _vertices[28] = new VertexPositionNormalTexture(btmLeftBack, normalLeft, textureBottomLeft );
        _vertices[29] = new VertexPositionNormalTexture(topLeftFront, normalLeft, textureTopRight );

        // Add the vertices for the RIGHT face. 
        _vertices[30] = new VertexPositionNormalTexture(topRightFront, normalRight, textureTopLeft);
        _vertices[31] = new VertexPositionNormalTexture(btmRightFront, normalRight, textureBottomLeft);
        _vertices[32] = new VertexPositionNormalTexture(btmRightBack, normalRight, textureBottomRight);
        _vertices[33] = new VertexPositionNormalTexture(topRightBack, normalRight, textureTopRight);
        _vertices[34] = new VertexPositionNormalTexture(topRightFront, normalRight, textureTopLeft);
        _vertices[35] = new VertexPositionNormalTexture(btmRightBack, normalRight, textureBottomRight);
        done = true;

    }