.TH LIGHTSPEED 1 "April 2000" .SH NAME lightspeed \- Shows how objects moving at speeds near the speed of light look like. .SH SYNOPSIS .BI lightspeed " [" \-hsa "] [" object ] .SH DESCRIPTION Light Speed! is a simulator which can illustrate the effects of special relativity on the appearance of objects travelling at ultra-high speeds. Depending on the particular speed, and one's point of view, relativistic effects can cause the object to appear shorter, longer, brighter, darker, deformed and/or off-color. .SH CONTROLS To adjust the velocity, use the slider along the right edge of the main window. You can also type in a value, using the entry at the top right (press once it is in). To change the units shown, press the button to the right of the entry, and it will cycle through a small list. .PP The object travels in the positive-x direction, which can be visually checked by activating Objects -> Coordinate axes. .PP Most interactive control is performed with the mouse. By holding down a particular button, and dragging the pointer around, various camera motions can be obtained: .PP .nf Left button: Revolve camera around view target Left button + Shift key: Revolve view target around camera Middle button: Translate camera left, right, up or down Right button: Dolly in or out .fi .PP The first and last motions are generally the most useful. Should the camera become difficult to control at any point, it may be re-initialized by selecting Camera -> Reset View. .SH OPTIONS .TP .BR -h ", " --help Print this help screen .TP .BR -s ", " --simple Use simplified interface .TP .BR -a ", " --advanced Use advanced interface (default) .TP .I object 3D file to load on startup (.3DS or .LWO)