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Holoscenes - Textures of the Earth

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What are these Images?

Well, they aren't satellite images, as some people assume.

Sometime around 1996 I began to dabble in mapping software, after having been intrigued and then frustrated with the quality of inexpensive road map products. As a programmer, I was fascinated as much by the process as by the product. At the same time, the internet was making access to government datasets easy and inexpensive.

It was easy to obtain algorithms for map projections, and I combined these into my first Windows cartographic tool written in C++. The first challenge was to read and interpret the SDTS file format that was used to deliver the USGS DLG datasets. Upon completion of version 0.1, I had an ability to import the datasets and display bitmaps containing road and stream networks in a flat but color-coded format.

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As I discovered additional datasets, I added routines to import and reconcile their separate coordinate systems and render their features. I encountered the Census Bureau's TIGER/Line® files while searching for political boundary files at the Ciesin site. Although the Ciesin site did not contain the raw Tiger/Line® data, they had distilled that dataset into easy-to-use FIPS, county, and state boundary files. Although the maps on this site no longer use the Ciesin datasets, their simple format survives to define some custom features such as the map outlines that are superimposed over the state insets on the gallery pages.

The next step was to add place and feature names using the GNIS dataset. At first I selected names externally with text manipulation tools, but the mapping program was acquiring an increasing number of interactive features, and soon its labeling feature was capable of selecting and placing names falling within a designated rectangle on the map. The first labels were quite simple and spare.

Although line maps were interesting and the process of making them was instructive, it was clear that physical features controlled the location and routes of most of the man-made structures the maps depicted. Motivated by a form of armchair adventure, I continued to search and discovered the LULC datasets that contained area features such as forests, rangelands, and urban areas. The new maps were vastly improved compared to the bare lines that preceeded them.

In 1997, I took my first trip to the American Southwest into the manifestly three-dimensional landscape of the Grand Canyon, Zion, and Bryce Canyon National Parks. Upon returning, I endeavored to enhance my maps with physical relief of some form. After acquiring several DEM datasets of the region, I produced the first shaded-relief map. When combined with land cover coloring, the effect was quite striking and beautiful.

Since then my efforts have been directed toward making the process easier and quicker, and adding the ability to produce maps at printer resolution. Although several (expensive) commercial GIS products are capable of producing similar maps, seeing these creations come to life through my own software is quite satisfying. I hope you enjoy them.

If you have suggestions or requests, I would like to hear from you. Please feel free to write to me at webmaster@holoscenes.com.


All maps and content Copyright (c) 1999-2001 James R. Irwin.