NAME

live − Mathematica animation tool

SYNOPSIS

live [−f] [−c config_file] [−title titlestring] [−sizex,y | −pos l,r,b,t] [file]

DESCRIPTION

Live lets you preview a 3Script file (standard input by default) while changing the viewpoint and other parameters in real time using the Silicon Graphics hardware.  The −title option lets you use an alternative title name over the default “Mathematica Live” title for the window.  The −size x,y option changes the default window size, and the −pos l,r,b,t option opens the window in the specified rectangle on the screen without asking the user for a rectangle. 

Live is usually invoked from inside Mathematica, using the Live function, as follows:

In[1]:= Plot3D[ Sin[x y], {x, 0, 3}, {y, 0, 3}, Lighting -> True]
Out[1]= -SurfaceGraphics-
In[2]:= Live[%]

You have a choice of either moving the graphics object, or moving yourself. 

Moving the Object

When moving the object, you can change its orientation or its distance.  Holding the middle mouse button down and dragging the mouse changes the orientation of the object.  Holding the left mouse button down and dragging the mouse up moves closer to the object.  Holding the left mouse button down and dragging the mouse down moves the object further away.  By default, live runs in this way.  Note that your live of sight stays focused on the center of the object, even when you reorient the object. 

Make sure you click the mouse button inside the live window.  Once the button is down, you can drag the mouse out of the window.  When you reach the edge of the Workstation screen, let go of the mouse button, go back to the window and click again. 

Moving Yourself

Sometimes it is important to be able to look in directions other than towards the center of the object.  In order to achieve this, you can run live with the -f option.  Now, the middle mouse button controls your heading, and the left mouse button lets you move forward or backwards.  This mode takes some getting used to, and it helps to remember that when you turn your head one way, the world goes the other way. 

MENUS

The right mouse button is the menu button.  Several menu selections are available, and they all have keyboard equivalents that appear in parentheses.  Not all the menu selection may be available for a given graphics object or workstation. 

twist clockwise(right arrow) / counterclockwise(left arrow). 
This options lets you change the orientation around the line of sight. Since the change is small, it is more convenient to use the right arrow key instead of this menu selection.

zoom in(x) / out(z). 
Changes the perspective by which you view the object.  As in the previous case, it is much more useful to use the keyboard equivalent.

materials.  A walking menu with alternative materials for the object’s surfaces. 

lights.  A walking menu with alternative lighting configurations. 

spin mode on/off (c). 
Changes the orientation of the object continuously, following the mouse position.

bounding box on/off (b). 
Toggles the display of the bounding box.

outlining on/off (o). 
Controls whether or not the outlining of the polygons should be displayed.

translucent/opaque surfaces (t). 
Toggles the translucency of the displayed polygons (GT only).

flat/smooth shading of surfaces (s). 
Enables you to interpolate the colors of the surface polygons.b

save configuration (w). 
See below.

reset (home key)
Returns to the initial position and flags.

exit (escape key)
Quits live. 

Configurations

You can customize live by building your own configuration file, that tells live the default values for all its flags, as well as alternative lighting configurations and the ALPHA (opacity) value for translucent surfaces.  The default configuration file is “.liverc” in the current directory, but thsi can be changed with the −c command-line option.  The file may contain empty and comment lines anywhere.  A comment line has a ‘#’ in its first column.  Each attribute has a separate line in the file, and the line starts with a keyword representing the attribute, and then its value.  Here is an example that illustrates the configuration file:

#configuration file for live

material 2
lightsources "Plain" 0 1 1 0.9 0.9 0.9
lightsources 1 0 1  1 0 0   1 1 1  0 1 0
lights 1
translucent 1
alpha 0.3
bb 0
outline 0
spin 0
smooth 1
bb_color 255 255 0
bg_color 5 5 255
outline_color 0 0 0

This example sets the default material to material number 2 instead of 0;  it sets two alternative lighting configurations: one named “Plain”, with a white light in position (0, 1, 1), and the other unnamed, with two lights: a red light in (1, 0, 1) and a green light in (1, 1, 1); the default lighting configuration is set to number 1 (the white light); by default, polygons are translucent with an opacity of 0.3 (the opacity is between 0 and 1, where 0 is transparent and 1 is opaque); the bounding box and the outlines are not displayed; surfaces are smooth by default; the bounding box color (if the user chooses to display it) is yellow; the background for the window is blue, and the polygon outline color (if the user chooses to display it) is black. 

When you select the reset menu option, live re-reads the configuration file if it exists.  This lets you fine-tune the opacity and colors semi-interactively by editing the configuration file as live is running. 

FILES

.SH DIAGNOSTICS .B "ERROR -- line # " .I nnn .B ", unknown token = " .I word: an error was encountered while reading the 3Script file.  .SH HARDWARE REQUIREMENTS 8 bits of z-buffer, and at least 12 bitplanes.  .SH "SEE ALSO" movie(1) .SH AUTHOR Yossi Friedman .SH ORIGIN Wolfram Research, Inc. 

Version   —  September 12, 1990