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Showing posts from October 25, 2009

### Mathematical Models of 3D Inputs Control

Perm url with updates: http://xahlee.org/3d/3D_inputs.htmlReview of SpaceNavigator ＆ Mathematical Models of 3D Inputs ControlXah Lee, 2009-10-27, 2010-08-06, 2011-04-04Discovered today about a 3D navigation input device, called SpaceNavigator. It is used for working with 3D applications.The SpaceNavigator. amazon SpaceNavigator controls. In working with many 3D applications in the past years, i've become interested in how all the different needs for 3D viewing or nagivation can be based on a simple mathematical model.Example of Different 3D ControlsHere are examples of different needs for 3D control.In flight simulation, you need to control the yaw, pitch, roll.In 3D Modeling Software, you want to focus on your object and be able to rotate it, zoom in/out. e.g. viewing molecules models, viewing commercial product online before buy.In Panorama applications, you want to rotate yourself, and also be able to zoom in out.In many First-person shooter games, you walk a character. So, you h…

### gattling gun

2009-10-28 While playing in Second Life, people have made guns that are multiple barrels that rotates. I've been curious about what's the name of such gun, its general history, technical reasons for their existence, and if such desigen is still relevant today.Such type of gun is called Gattling gun. Today, we have single barrel guns that fires continuously and rapidly. (e.g. big ones with bullet belts are known as Machine guns and we have what's called automatic pistols, rifles, shotguns. Technically, all these are called Fully automatic.) The technology of guns with multiple barrels that rotates, is still used today. The main advantage is that, single barrel guns that fire too rapidly would get too hot, by the mere fact of too many bullets going thru it too fast. So, there's the rotation of barrel, which solves the overheating problem, but also provide simultaneous ejection and installation bullets that are needed.2009-10-26 Found interesting articles today.Nicole B Ell…

### insect fight, videos, communication tech and the progress of human animals

2009-10-23 Some amazing videos.Video of insect fights. You have Mantis, spiders, centepeds, wasps, scorporions, Atlas beetle, Hercules beetle, and even shrimp!. Look at the following 2, wasp vs scorpion. In one of them, wasp won, but the other, the wasp got stung dead by the scorp. http://www.japanesebugfights.com/2.htmhttp://www.japanesebugfights.com/15.htm. In this one, http://www.japanesebugfights.com/4.htm wasp vs centepede, the wasp is aggressive, but loses.This one, atlas beetle vs hercules beetle. http://www.japanesebugfights.com/5.htm.This one, wasp vs centipede: http://www.japanesebugfights.com/12.htm. The wasp got killed by the venom.Youtube video search: mongoose. Mongoose fighting snake. Also, lots of other animal fights, e.g. cat vs snake, etc.A guy cutting off his penis and balls. http://www.muchosucko.com/show/bme_pain_olympics_finalists-26629/searchAmazing. With the rapid advance of communication techonolgy, in particular the internet, we can watch all sort of things r…