10 February 2005

GoogleMaps : http://maps.google.com/ the map itself, is broken up into a grid of 128x128 images (basically like an old tile-based scrolling console game). The dragging code (JavaScript) is nothing new, but the cool trick here is that each of these images is absolutely positioned -- and the 'infinite' scrolling effect is achieved by picking up tiles that are off-screen on one end and placing them down on the other end. The effect is kind of like laying track for a train by picking up track from behind it likely that they've pre-rendered the entire map beforehand; the map tiles are entirely static and prebuilt for the various zoom levels. Brilliant approach to an otherwise painful load problem (smallest tiles are about 1/10 of a mile on the side, and if the covered area is about 2000 x 3000 miles, that's 6 x 10^6 square miles or 6 x 10^8 tiles. An empty tile is about 150 bytes, complicated ones are around 3kb, but if we guess the average one is around 1kb, we're talking 6x10^11 bytes, or 600 GB; you could store it all on < $500 of hard drives). .. build a system that can keep it all in RAM, can serve 19 million maps per second. .... push-pins and info-popups are a different matter. Simply placing them is no big trick; an absolutely-positioned transparent GIF does the trick nicely. The shadows PNGs with 8-bit alpha channels .... JavaScript actually uses the XSLTProcessor component to apply an XSLT to the result XML. This generates HTML which is then shown in the right panel .... giant transparent PNG for rendering routes ... from http://jgwebber.blogspot.com/2005/02/mapping-google.html Slashdot discussion : http://slashdot.org/article.pl?sid=05/02/08/0926214&tid=217&tid=1

(United States Patent 6,724,382 Kenyon, et al. April 20, 2004) Method and apparatus for distributing and displaying maps electronically :

Cross-Browser Variable Opacity with PNG: http://www.alistapart.com/articles/pngopacity/

One Land Two Systems : http://www.onelandtwosystems.com/article-201.3624-en.html

The Stereos tropic landscape: The Stereos tropic Spectator, that the historian Jonathan Crary writes, as a radical repositioning of the observer's relation to visual representation…The stereoscope signals an eradication of "the point of view" around which, for several centuries, meanings had been assigned reciprocally to an observer and the object of his/her vision. There is no longer the possibility of such a technique of beholding. The relation of observer to an image ( territory) is no longer to an object quantified to a position in space, but rather to two dissimilar images whose position simulates the anatomical structure of the observer's body." : http://www.onelandtwosystems.com/person-201.3354-en.html?note_form=1

Florence Nightingale's rose diagram ; she invented them and used three rose diagrams in succession in a deliberately calculated rhetorical message to military and government leaders. Her three rose diagrams are considered to be a visual and rhetorical tour de force. http://www.agnesscott.edu/lriddle/women/nightpiechart.htm

"Why aren't there really good answers to Frequently Asked Questions ?" - Ron Wild
"You can change how you feel in the twinkling of an eye, if you just change what you view as important." - The Universe

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