XNA Game-Themed
Programming Assignments
Kelvin Sung
Computing and Software Systems
University of Washington, Bothell
Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010
Idea

Given a “Starter Project” with
All Graphics and User support
Does not work!




Students complete the system by implementing
the “missing piece”
Support Professors who does not know any graphics or
games programming!
Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010
Our Approach: Game-Themed Assignment

A set of Programming Assignment Modules …
Designed to be adopted selectively in existing classes
No requirements on knowledge of graphics or gaming



7 assignment modules on well defined CS1/2 topics:
For example: 2D Array / BST / Lists etc.


Each module includes 2 versions:
Game-themed and “traditional” console version
Console version is a good reference
Based on the same topics, the two versions may be
different: e.g.:




2D Array / BST / Lists
Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010
Assignment Module: Contents

For Faculty:
Summary page: prerequisite + learning outcomes
Sample pre and post-tests
Sample solution: console / XNA
Sample Grading rubric (console / XNA)
FAQs
XNA Implementation Guide: on Graphics + UI







For Students:
Description of the assignment (console / XNA)
Skeleton starter project (console / XNA)


Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010
All The Assignments

XGA ReleaseNote

Operator:
Console, XNA Starter, XNA Solution
Random Numbers & Arrays:
Console, XNA Starter, XNA Solution
Array of Object References:
Console, XNA Starter, XNA Solution
2D Array:
Console, XNA Starter, XNA Solution
Class Hierarchy:
Console, XNA Starter, XNA Solution
Linked Lists:
Console, XNA Starter, XNA Solution
Binary Search Tree:
Console, XNA Starter, XNA Solution













Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010
Starter Project


Our experience:
Students must modify same source code
E.g., Operator:



Console, XNA Starter, XNA Solution
Students are given a well defined API
E.g., BST:


Console, XNA Starter, XNA Solution
Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010
Example XGAs:
Switch, Modulus, Integer Division

What Worked Well:



Graphical, interactive
Forced students to think about things like mod operator, in
an open-ended / real-world-ish sort of way
What Didn’t Work So Well:

Students can do this without integer division


(Do real division, then cast to int, then do mod)
One can’t really solve this without some understanding of
the video game structure – Color.Red, or a clear view of
the coordinate system.
Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010
Example XGAs:
Binary Search Trees

Students implement a BST of chars






Add( char c )
Find( char c )
int FindTreeDepth()
Clone() -> new, deep copy of the tree
void Balance() // balances existing nodes in-place
Students do NOT implement:

BST also has an in-order traverse method, privately
implemented in the base class, so that the video game
works, but doesn’t give away answers
Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010
Example XGAs:
Binary Search Trees

What Worked Well:




Graphical, interactive
Nicely isolated BST – students really did not have to know
about the gaming aspects
Could potentially re-use Console based stuff, including
unit tests, etc
What Didn’t Work So Well:

Example being too “academic”?
Serious Game Winter School, Puerto Vallarta, Mexico, Feb 2010