Web Mapping Illustrated


Tyler Mitchell's Web Mapping Illustrated, published by O'Reilly, could have spared me about a week of hair-pulling back in 2000 when I was just beginning to discover open source GIS software. Our projects are reasonably well documented, and there is an enormous amount of knowledge within the community, but there has never before been a broad and coherent synthesis of that information. Finally, new users can see the entire domain of open source mapping from data creation, to data processing, to digital map. We've needed this book for a long time.

We expect O'Reilly books to be excellent productions, and indeed it is. In appearance, style, and scale, it is like the Web Services Essentials and SVG Essentials -- also edited by Simon St. Laurent -- but has a larger format, better paper, heavier binding, and copious color illustrations. The book takes on a big workflow and diverse tools, but Tyler manages to keep it together with a consistent mapping narrative, clear writing style, and concrete, replicable examples.

Highlights of Web Mapping include:

  • 17 pages on installation of MapServer from binary or source distributions.

  • Thorough overview of inspecting vector and raster data with ogrinfo and gdalinfo. I was reminded that OGR is geared towards working with directories of shapefiles, something I hadn't fully appreciated.

  • Two chapters on MapServer configuration and templating. I'm a stickler for mapfile style, and Tyler's is worth emulating.

  • Excellent chapter on configuring MapServer to provide and consume OGC web map and feature services.

  • The best existing overview of PostGIS, at least until somebody writes PostGIS in a Nutshell.

  • Nice introduction to programming with MapScript. Tyler even chose the right language for all his primary examples :)

I would have liked to have seen Tyler take on some of MapServer's anti-patterns, or help users avoid these 300 layer map config files we keep hearing about on the mapserver-users list. I also disagreed with his use of PostGIS geometries as unique keys for spatial sub-selects in Chapter 13. Spatial tables should always be provided with a lightweight unique identifier for this purpose. The book also suffers a bit from too many color screenshots of OpenEV. Powerful as it may be, OpenEV's primitive interface isn't going to sell any copies of this book.

I also wonder whether or not Google, which launched their web map just as this book was going into print, hasn't permanently altered the meaning of "web mapping" and thus moved the book's target. Now, to most of the IT world, Google's map is web mapping; there is one web map, and it's all a matter of annotating it with your own points. A distinction between Tyler's workflow and tools, and what the masses call "web mapping" is important.

In my estimation, users of ArcIMS/ArcSDE who are looking to broaden their horizons will find Web Mapping slightly too introductory, but a still valuable aid in getting over the first humps. Definitely worth buying. IT and Web professionals looking to break into geospatial and mapping work will find this book to be the ideal starting point, as will those who are graduating from Google map hacks to more unique and data-dependent applications.