Book Image

XNA 4.0 Game Development by Example: Beginner's Guide - Visual Basic Edition

By : Kurt Jaegers
Book Image

XNA 4.0 Game Development by Example: Beginner's Guide - Visual Basic Edition

By: Kurt Jaegers

Overview of this book

XNA Game Studio enables hobbyists and independent game developers to easily create video games, and now gives that power to Visual Basic developers. XNA lets you bring your creations to life on Windows, the Xbox 360 and the Windows Phone platforms. The latest release of XNA has added support to Visual Basic and therefore, Visual Basic developers now have the power to give life to their creativity with XNA.This book covers both the concepts and the implementations necessary to get you started on bringing your own creations to life with XNA. It presents four different games, including a puzzler, space shooter, multi-axis shoot 'em up, and a jump-and-run platformer. Each game introduces new concepts and techniques to build a solid foundation for your own ideas and creativity.This book details the creation of four games, all in different styles, from start to finish using Visual Basic and the Microsoft XNA framework. Beginning with the basics of drawing images to the screen, the book then incrementally introduces sprite animation, particles, sound effects, tile-based maps, and path finding. It then explores combining XNA with Windows Forms to build an interactive map editor, and builds a platform-style game using the editor-generated maps. Finally, the book covers the considerations necessary for deploying your games to the Xbox 360 platform.By the end of the book, you will have a solid foundation of game development concepts and techniques as well as working sample games to extend and innovate upon. You will have the knowledge necessary to create games that you can complete without an army of fellow game developers at your back.
Table of Contents (16 chapters)
XNA 4.0 Game Development by Example – Visual Basic Edition Beginner's Guide
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
4
Asteroid Belt Assault – Lost in Space
Index

Time for action – filling in the gaps


  1. Add the FillFromAbove() method to the GameBoard class.

    Public Sub FillFromAbove(x As Integer, y As Integer)
      Dim rowLookup As Integer = y - 1
    
      Do While (rowLookup >= 0)
        If GetSquare(x, rowLookup) <> "Empty" Then
          SetSquare(x, y, GetSquare(x, rowLookup))
          SetSquare(x, rowLookup, "Empty")
          rowLookup = -1
        End If
        rowLookup -= 1
      Loop
    End Sub

What just happened?

Given a square to fill, FillFromAbove() looks at the piece directly above to see if it is marked as Empty. If it is, the method will subtract one from rowLookup and start over until it reaches the top of the board. If no non-empty pieces are found when the top of the board is reached, the method does nothing and exits.

When a non-empty piece is found, it is copied to the destination square, and the copied piece is changed to an empty piece. The rowLookup variable is set to -1 to ensure that the loop does not continue to run.

Generating new pieces

We can create a single...