graduate level courses taught in the Department of Agri-
cultural Engineering at Purdue University. These
courses are GIS and Watershed Systems Design (AGEN
526) and GIS Applications (AGEN 591s). The NCGIA
materials incorporated into Hyper-GIS were from the
first two volumes.
4.2 System Design
We used HyperNeWS to design the Hyper-GIS system.
HyperNeWS is a hybrid object-oriented tool in the sense
that the basic object types are created with a classing
mechanism similar to that of the Smalltalk software and
the C++ language, but user-defined types are created
from object templates or prototypes. We designed
Hyper-GIS as a stack, consisting of a groups of cards.
A HyperNeWS stack consists of one or more cards, con-
ceptually stacked on top of one another so that only one
card is visible at a time. Behind a card resided the back-
ground, which belonged to one card or was shared
among a number of cards in the stack. If a group of
cards shared a graphic or a button, we only created it
once and made it a shared background. Each card con-
sisted of a number of objects. Currently, HyperNeWS
supports six types of objects which can reside on a card,
including buttons, menus, and textfields. According to
the needs, objects were assigned to either a card, a back-
ground, or the system stack itself. By attaching an object
to the stack, we always saw the object no matter which
card or background was currently being displayed.
In order to make the feature of sound supportable in
HyperNeWS, we programmed routines and interfaced
them to HyperNeWS. Therefore, the enhanced Hyper-
NeWS provided a variety of media, including text,
graphics, images, sound (voice), and animation (motion
pictures). A sound button was designed to control the
volume of sound or turn off sound. Like other types of
buttons, this button can be attached to stacks and cards.
For example, the sound button is used to play the
recorded water flowing through a gage while viewing
the gage station.
We designed key terms or topics of GIS materials in red
color fonts, which referred to a hyper-link behind each
red textfield. It was also called a hot key. This ability
allows students to click on a red textfield and reach the
definition or the details about the text.
4.3 Hyper-GIS
Main Menu and Global Buttons: The Hyper-GIS system
is menu-driven (Figure 1). The textfields of Section 1,
Section 2, Section 3, and Section 4 contain hot keys so
that students are guided to each section of Hyper-GIS by
clicking on these hot keys. For example, students are
guided to Section 1, Introduction to GIS, by clicking on
the hot key Section 1 (Figure 2). At the bottom of the
menu, seven types of buttons were designed and
attached to every text template. Button Done exits
Hyper-GIS. Button top sends the current display to the
main menu, as shown in Figure 1, no matter where the
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previous display was located. Button previous sends the
current display to a logically-previous object. Button
next sends the current display to a logically-next object.
Button up sends the current display to its parent-level
menu. Button recent sends the current display to the
object which happened most recently. Button index
sends the current display to the index card. With the
index button, students can search any term, section, or
topic of interest and discover the corresponding details.
Graphics, Images and Intuitive Display: Graphics and
images played an important role in Hyper-GIS. Graphics
usually consisted of images. Hyper-GIS provides an
intuitive illustration to the GIS component (Figure 3).
Images were incorporated to make this figure intuitive.
From this figure, students can learn how a GIS layer was
stored in a spatial database, what types of data a DBMS
deals with, what kinds of output we can get, etc. In
teaching GIS, concepts of Raster and Vector (Figure 4)
are not easy to be explained, especially for those stu-
dents with little background with computer graphics.
Figure 4 including two images, intuitively shows Raster
and Vector side by side, and the difference of Raster and
Vector can be easily visualized by students. Students
can also learn what spatial data look like through a spa-
tial image shown in Figure 5.
Hot Keys about Details: Hot keys take students to the
details of the highlighted keys. For example, by clicking
on the first hot key in Figure 6, students can get details
about the maintenance and analysis of the spatial data
(Figure 7). The hot keys can be added to or removed
from Hyper-GIS based on requirements.
Indices and Random Access: Whenever students want to
learn and review terms and topics, they can click on the
index button anywhere in Hyper-GIS and then be taken
to the index section. Form the index, they can choose a
pre-designed item of interest. Index searching was
implemented with hot keys in the index section (Figure
8). After the searching, students were sent back to the
index card when clicking the GoGIS button. This sec-
tion can also be updated based on requirements.
Animation and Sound: With animation, natural scenes
can be created on a computer. Sound can be used as an
auxiliary feature to enhance the animation. In Hyper-
GIS, we used animation and sound to create a scene of
the flowing water through a gage (Figure 9). Pre-
recorded sound of the flowing was simultaneously
played.
GIS Applications: As previously mentioned, three GIS
applications describing watershed management models
were incorporated to teach students each model and
implementation of a GIS project. For example, Figure
10 shows how Hyper-GIS demonstrates that a runoff
spatial map can be obtained with the addition of a
curve-number map and a rainfall map.