Texas Blind Catfish |
Two Texas blind catfish specimens were used for a 3D animation in World of
Water exhibit at Witte Museum. In order to capture 3D information, Dr. Susan Hovorka
and Dr. Dean Hendrickson arranged two specimens to be X-ray scanned using
Computed Axial Tomography at the High Resolution X-ray CT facility at the
University of Texas. The two specimens that were scanned were Trogloglanis
pattersoni and Satan eurystomus; both species are found naturally in the
Edwards Aquifer in the San Antonio area. The specimens are part of the
Texas Memorial Museum collections at the University of Texas. Both specimens
were mounted on a wet sponge and X-ray CAT scanned simultaneously by
Dr. Julian Humphries. Two scans were done,
a low resolution scan and a high resolution scan. For the World of Water,
exhibit only the low resolution scan was used. The X-ray scanner generated
a stack of parallel 2D images that formed a 3D block volume. The 2D images
were processed by Reuben Reyes to create 3D models. Using 3D software, the
two specimens were digitally separated. Each specimen was digitally retouched
due to data loss in the thinner areas of the fins and whiskers. The sponge that
the specimens laid on was also digitally removed. The specimens were laid out
very well for the X-ray scan but the orientation of both were curled so that
both would fit in the circular X-ray scanning window. The goal for the World of
Water exhibit was to make the two 3D models digitally swim and move realistically
for an animation, in order to do this both 3D models were digitally straightened
out so that the spine was straight and not curved. Once the specimens were
straight, a tail movement and fish swim movement
were added digitally. This movement can be seen in the VRML models and were
also used to make the animations for the World of Water exhibit using
3D Studio Max. Color was added to the skin surface from photographs of both
species to give a more realistic rendering. In the final render of the
animation, the skin color was made to look bluer to match the water color
in the animation. The VRML models on this page were reduced in size using
a facet reduction called decimation. This was done so the 3D models would
be easer to download and view but beware that the models are still
large. You will need a high speed connection, a fast graphics card and VRML
plug-in to view. Below are static and swimming 3D models of both
Trogloglanis pattersoni and Satan eurystomus in VRML format. Click
on images to view VRML models.
Blindcats
| Trogloglanis pattersoni
| Satan eurystomus
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Static Models
| Size 2301 Kb
122485 facets
| Size 2435 Kb
102834 facets
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Swimming Models
| 5965 Kb
122485 facets
| 8231 Kb
102834 facets
|
Common Name
| Toothless blindcat
| Widemouth blindcat
|
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Earth and Sun |
The final product of the World of Water project was an animation; it starts and ends with a view from space of the Earth and Sun.
The Earth was created with digital elevation maps from USGS and the color or texture was from NASA satellite images.
The Earth VRML model on this page is a simple version of Earth the actual version used was very large and complex. The complex version of Earth contained 4 levels of detail
for a zoom into central Texas. The Sun was made with perlin noise to simulate the surface texture of the Sun. To simulate the Sun
surface three spheres were used, each with a different perlin noise pattern. Each sphere was of a different size and was texture
mapped as semi-transparent. The spheres each with perlin noise and semi-transparency were then set in motion. This was to give the illusion
of a volatile moving surface. The outer most sphere was set to rotate via the x axis, the middle sphere was set to rotate via the y axis,
and the inner sphere was set to rotate via the z axis. A program was written to create the spheres of the Earth model with elevation
and of the Sun model. The program also had an option to include the texture maps. Programming and VRML models of the Earth
and Sun were produced by Reuben Reyes. Other VRML models of the Solar System made with the same program can be found at
VRML Models of the Solar System . Click on images below to view VRML models.
The Earth.
129,600 facets : File 1,999 KB.
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The Sun.
24,300 facets : File 314 KB.
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