Information Technology Reference
In-Depth Information
serve all three of our case studies, does not include a procedural level generation sys-
tem or an integrated level editor. We have replaced this component with a designer's
notebook style feature for storing and tagging ideas, design patterns and work-in-
process levels, which can then be filtered according to data created in the progression
plan component. We have also extended the constraints and progression plan compo-
nents, adding additional calculations and visualization features, including a graph
traversal algorithm to the progression plan component in order to apply constraints to
non-linear level progressions.
4.1
Progression Constraints Component
As in
Refraction
's tool, our progression constraints component allows the game de-
signer to create game elements and constraints by defining some elements as explicit
prerequisites and co-requisites of other elements. An element can be as concrete and
quantifiable as an ammo pickup, for example; or a quality the level might contain like
“intense combat”. As well as providing a matrix-style editor, the tool automatically
infers transitive prerequisites (as does
Refraction
's tool). This is a non-trivial calcula-
tion for a designer to perform manually.
Graph and Matrix Interfaces
To this component we have added an editable graph-based view as an alternative to
the matrix view. We chose to include a graph-based view upon discovering that the
progression plan for our adventure game could be in fact better described and sup-
ported by taking the form of progression constraints, leaving the progression structure
itself for managing the higher level episodic narrative. As in matrix view, graph edges
are automatically added when constraints are transitively inferred by the tool. This
kind of computational support is useful for managing the binary but complex progres-
sion logic of an adventure game.
4.2
Progression Plan Component
Graph Interface
The most signification modification we have made to
Refraction
's approach is ex-
panding the progression plan out from their linear table form into a graph-based editor
and analyzer. A graph allows for games that have a non-linear progression structures
to be modeled. The designer uses the graph interface to create levels or mission stages
as nodes and define connections between them as edges. He or she can select a node
in the graph to edit the properties of the associated level.
Game Elements List
Alongside the graph interface we display a list of all game elements. Any element in
the list may be selected and added to the level's game elements list. The elements in
the list are displayed differently, according to their eligibility for use in the currently
selected level: eligible, ineligible and potentially eligible. Eligibility is based on the
