I used to post frequently on several computer graphics, animation, and video oriented mailing lists. A contractor working on research for the Defense Intelligence Agency saw my posts and asked me questions about how to render terrain and atmospheric phenomenon. During the conversations he convinced me to join the effort.

Officially this work was described as "in support of American troops in the Middle East" due to the politically sensitive nature of the geography involved. For all practical purposes this was really to assist in the national defense of Israel.

This is all considered unfinished/prototype work. A few images were produced that were displayed to people as examples of the product this effort could create. The goal was to be able to produce realistic animations of views of "atmospheric phenomenon" over the "area of interest". This required effort to model the ground of the area of interest and then add an accurate rendering to represent the atmospheric phenomenon.

Some working proofs of early animation concepts were produced in Lightwave using lower resolution, faux-terrain data. The real animations of terrain were expected to be done in World Construction Set using satellite-collected, DTED data sets for the surface topography. The atmospheric phenomenon data was to be generated by another group of people on a supercomputer. I was to write software to translate the supercomputer-produced data sets into 3D graphic objects representing the shape and density (read: toxicity) of the atmospheric phenomenon and Lightwave would render the atmospheric objects over the terrain images rendered by WCS.

The contract was cancelled for basically unimportant reasons unrelated to the actual work. All the work that was completed was done on the Amiga. Our bid for the contract price was only about 20% (if I recall correctly) of the next lowest contract bidder.

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 First Color Map Rendered Terrain Image

This is the first presentable rendering of terrain in the area of interest done using Lightwave. The data used for the ground is VERY inaccurrate. What you see is simply a satellite photo taken of the area of interest laid down on a flat plane. The color picture was converted to a black and white photo (Art Department Professional) which I then touched up by hand (Deluxe Paint IV) to simulate the land topography with high points as white and low points as black and intermediate levels as shades of grey. This image was then laid down on the plane to describe the altitude of the ground. It it very inaccurate, but it looks convincing.

 First Animation Frame of Color Map Rendered Terrain

This is the first frame of an animation (150 frames, I think) done entirely in Lightwave to demonstrate the concept of doing flybys over terrain. The camera view moves closer to the terrain and flies a couple circles around the land. Halfway through the animation the camera spins around to look behind itself, so that the viewer is traveling backward. One very clever feature of the animation is that the words labelling points of interest in the view continually turn to face the camera, so that they are always readable.

 Latitude and Longitude lines Overlaid on Terrain

This is a test frame of my experiments to use features of Lightwave to draw graphics lines on terrain. The purpose was to be able to draw illustrations and map points of interest on the land. The ground is grey, because the color image used is actually the greyscale picture used for the altitude mapping.

One ugly problem is caused by the map supplying the green lines being too low-res. So, Lightwave "smooothed" the lines by blurring them which makes the lines look fuzzy. I suppose this could be useful in the right circumstances, but not here.

 Last Animation Frame of Atmospheric Rendering Test

This is the last frame of an animation done in Lightwave to demonstrate how atmospheric phenomenon might be rendered. In the animation a small cloud expands and drifts with the wind. The various colors represent density of the atmospheric phenomenon.

The purpose is just to simulate the visual representation, not show real data. The ground is the same ground used for the inital flyby animation, used here only to show some kind of terrain in the view. Accuracy was not important. For instance, if this view occurred in the actual area of interest, the cloud expansion from east to west would instead progress from west to east.

One ugly problem with the rendering is that the scale for the altitude mapping was increased dramatically. This is what gives the land the horribly jagged and vertical appearance. I don't know why I wasn't paying more attention and fixed it before rendering. Probably, because I was busy making the clouds look convincing.

 Early Test of Rendering DTED Terrain Data

This is a rendering done in World Construction Set of a large set of the satellite-collected digital terrain data (DTED) of the area of interest.

Note that the DTED data only describes altitude. Ordinarily without any other kind of information the program will render this generic altitude data in grey. Great for doing lunar simulations. Bad for earth terrain.

A very simple option supported by the World Construction Set program is to assign types of terrain (called ecosystems) to varying altitutes. In this picture the bulk of the land is assigned a "grassy" ecosystem, while the highest elevations are assigned "snow". The program is also smart enough to transition the green grass to bare rock before rendering snow caps on hills and it knows that snow collects in gullies at slightly lower altitudes than the actual snow line.

This generic ecosystem simulation makes the rendering look much better, but it still is very unrealistic. In the distance is a large flat area that should be rendered as a large lake. The problem with this area of terrain is that the lake is at a higher altitude than much of the land in the foreground. In fact, some of the foreground land is even below sea level. So, if the altitude method was used to choose to render water at sea level or at the lake level, then water would cover the land in the foreground.

The solution to the problem of rendering ecosystems on terrain is to have data that describes the ecosystems on the land in addition to the simple altitude data. While World Construction Set supports some official formats for ecosystem data it turned out to be next to impossible to aquire the appropriate Ecosystem data for the area of interest. A manual solution was devised for the following rendering.

 Rendering DTED Terrain Data with Ecosystem Color Maps

This is a rendering done in World Construction Set of a the satellite-collected digital terrain data (DTED) of the area of interest.

This view is close to the lake that was rendered in the previous picture as a flat, grassy plain. This improved rendering was achieved by exploiting World Construction Set alternate method for specifying Ecosystem information.

I used World Construction Set to save the DTED data in sections as graphics pictures. I loaded the pictures into a paint program and every place I could identify as the lake I painted the same color (blue, in this case, for easy reference) and black for everything that is not part of the lake. Then I instructed World Construction Set to use the blue color in the pictures as a water ecosystem. Finally I directed World Construction Set to load the modified graphics pictures and use them as ecosystem information for the corresponding terrain. The end result is the lake renders where it is supposed to be.

To produce a truly convincing rendering using real ecosystems (in lieu of having real ecosystem data) a lot of time would have to be spent analyzing satellite photos and hand tuning pictures used as ecosystem information.

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