3D Madness! Companion CD/3DMADNESS.iso/vistapro/vp1/manual/appb.txt

Text File | 1993-08-03 | 8KB | 180 lines

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Appendix B
Vistapro User Manual
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THE LANDSCAPES


Most of the landscape DEM files were obtained from the USGS and
are accurate to within 7 meters. Some of the files were
assembled to fit into Vistapro and therefore may not be perfect
where they are joined.

ELCAP.DEM
---------
ElCap is a section of Yosemite Valley in California out of
which rises El Capitan, a very large (about 1000 meters)
granite cliff formation at coordinate 2520,5760 (X, Y) in the
DEM data. This landscape was created by joining together two
USGS DEM files and then clipping out the section of interest. A
small "scar" that runs North/South where the USGS data did not
quite line up can be seen. The joining scar is most apparent in
the Valley with the sun shining from the east or west at
approximately 3400,4980. This DEM file is as accurate as the
original USGS data.

HALFDOME.DEM
------------
The Half Dome section of Yosemite Valley contains the famous
granite formation know as Half Dome at location 5100,7260. The
method used by the USGS to digitize the terrain led to some
distortion at the top and edges of Half Dome. The jaggy bump at
the top of Half Dome is a USGS artifact. This DEM file is as
accurate as the original USGS data since it was simply clipped
out of one DEM file.

CRATERL.DEM
------------
Crater Lake is the caldera of an ancient volcano in Oregon. The
walls of the caldera rise approximately 1250 meters from the
bottom of the lake to the top of the caldera. The DEM data
includes the underwater elevations. The lake fills the caldera
to a level about half way up the walls. The mound near the west
edge of the caldera is Wizard Island. It is separated from the
edge by the lake. The circular mound near the top of the
caldera is completely submerged. The lake can be filled with
water using the Lake function of Vistapro. Clicking the mouse
button about halfway from Wizard Island to the edge of the
caldera gives approximately the right water level. In order to
include the entire lake in the file, everything was adjusted
down by a factor of 0.6. Therefore, to convert elevations or
distances into actual meters, take the values given by Vistapro
and divide them by 0.6.

MSHB.DEM and MSHA.DEM
---------------------
Mt. St. Helens is the volcano in Washington that blew its top
on May 18, 1980. The explosive eruption was preceded by amounts
of intense earthquake activity. A 150 meter bulge started to
grow in April at a rate of 5 meters per day. A magnitude 5.1
earthquake set into motion the collapse of the bulge and the
following explosion. Winds from the blast were calculated at
670 miles per hour. Almost everything within 8 miles of the
blast was obliterated. Virtually all trees were flattened at
distances up to 19 miles from the volcano. Significant amounts
of volcanic ash fell as far as one thousand miles away. The new
crater is about 3 kilometers wide and 700 meters deep. The
"before" data was generated from stereo photographs taken in
1979. The "after" data comes from photographs taken late in
1980.

MONS.DEM
--------
Olympus Mons is a huge volcano on the surface of Mars that is
roughly twice as tall as Mt. Everest on earth! It is about 500
kilometers in diameter and rises approximately 18 kilometers
above the surrounding landscape. The original DEM file which
contains the entire volcano is over 4 megabytes! The DEM file
included here contains only the interesting caldera portion of
the volcano. The technique used by the USGS to generate this
kind of extra-terrestrial data creates extensive artifacting
resulting in raked lines in the landscape. One or two smoothing
passes will remove these artifacts. The data on the vertical
axis is exaggerated by 4 fold to make the landscape more
dramatic. Elevations are measured from an arbitrary reference,
because there is no sea level on Mars.

JULIA.DEM and MANDELBR.DEM
--------------------------
Julia and Mandelbrot landscapes are artificially generated by a
mathematical algorithm. The user may have seen Julia sets and
Mandelbrot sets displayed as colors on a 2-D screen. If the
user has a Mandelbrot generating program that will handle Julia
sets, or a Julia generating program, the locations are as
follows: The Mandelbrot is 1.255525 real -0.381060 imaginary,
with a diameter of approximately 0.007; the location of the
Julia set is 0.75 real -0.11 imaginary, relative to the
Mandelbrot set.

ARROWHD.DEM
-----------
This is the Lake Arrowhead region of the San Bernardino
Mountains in Southern California. The low-lying region forms a
lake that is in the shape of an arrowhead, hence the name. The
lake was formed by the addition of a man-made dam, which is not
part of the DEM data, so it is impossible to fill the lake
without flooding the landscape below. This is clipped from a
larger data set that is also available from VRLI, called "Lake
Arrowhead and Environs".

VANTAGE.DEM
-----------
This is a portion of the Columbia River in the state of
Washington that forms the north portion of Wanapum Lake. It is
located in Ginkgo State Park near Vantage, Washington.

SANLUISO.DEM
------------
This is the area that we see when we look out our windows. VRLI
is located toward the southeast portion of the topographic map.
The mountains are not of spectacular height, but it forms quite
a pleasing landscape.

SANGORGO.DEM
------------
This is south of the Big Bear Lake region of the San Bernardino
Mountains in Southern California. It contains Mt. San Gorgonio,
a 3500 meter peak in an area known as the San Gabriel
wilderness. This is clipped from a larger data set that is
available from VRLI, called the "San Gorgonio Mountain and
Environs".

BIGSUR.DEM
----------
This is the Big Sur area along the coast of north central
California, just south of the Monterey Peninsula. It contains
the Pfeiffer Big Sur National Park. It is one of the more
beautiful camping areas in California, and contains one of the
southernmost groves of redwoods. It is clipped from a larger
data set that is available from VRLI, called "Big Sur and
Environs".

MORROBAY.DEM
------------
This is the data set for Morro Bay, one of our local tourist
attractions on the central coast of California. There is a
large rock that juts up into the fog called Morro Rock. This is
visible as a mound in the northwest corner of the topographic
map.

MTBALDY.DEM
-----------
Contrary to popular belief there is no such mountain as Mt.
Baldy in southern California. That is the name of the village
on the slopes of Mt. San Antonio. This is located in the San
Gabriel mountains south of Wrightwood. This has been clipped
from a larger data set that is available from VRLI, called "Mt.
Baldy and Environs".

MTADAMS.DEM
-----------
This contains Mt. Adams, in the southern portion of Washington
State. It is part of the Mt. Adams Wilderness, and is a good
example of a volcano, reaching from a height of over 3700
meters at its peak. It was clipped from a larger data set that
is available from VRLI, called "Mt. Adams and Environs".

WOODSH.DEM
----------
This is the first of our undersea data, a volcanic region
located at 21 degrees 13 minutes north and 166 degrees 24
minutes east, 500 miles north of Wake Island. This is actually
several thousand meters below sea level, but has been scaled to
appear above sea level for rendering purposes.


*** End of Appendix B ***