Provided by: xscreensaver-gl-extra_5.08-0ubuntu3_i386 bug
 

NAME

        crackberg  -  Lose  your  way  wandering  some height fields, and enjoy
        candy.
 

SYNOPSIS

        crackberg [-root] [-window] [-install]  [-display  host:display.screen]
        [-visual  visual] [-window-id id] [-delay usecs] [-fps] [-crack] [-lit]
        [-boring] [-letterbox] [-flat] [-wire] [-nowater]  [-visibility  float]
        [-color string] [-nsubdivs integer]
 

DESCRIPTION

        Flies  through  height maps, optionally animating the instantiation and
        destruction of generated tiles; by default,  tiles  'grow'  into  place
        (height gradually increased up to correct value).  In windowed mode the
        following key controls are available:
 
        left, right
                Turn left and right.
 
        a,w,s,d Move left, forwards, backwards, and to the right, respectively.
 
        1,2     Decrease and increase manual speed, respectively.
 
        Spacebar
                Return to automatic control.
 

OPTIONS

        crackberg accepts the following options:
 
        -root   Draw on the root window.
 
        -window Draw on a newly-created window.  This is the default.
 
        -install
                Install a private colormap for the window.
 
        -visual visual
                Specify  which  visual  to use.  Legal values are the name of a
                visual class, or the id number (decimal or hex) of  a  specific
                visual.
 
        -delay microseconds
                Delay between frames; default 20000 (1/50th of a second).
 
        -fps    Display the current frame rate, CPU load, and polygon count.
 
        -crack  Use all possible methods to animate tile instantiation.
 
        -boring Do  not  animate  instatiation at all; use this to get standard
                landscape generator behavior.
 
        -letterbox
                Drawable window region has a 16:9 aspect ratio,  regardless  of
                actual window size.
 
        -lit    Enable lighting.
 
        -flat   Flat  shading  (OpenGL will use one color per primitive, rather
                than interpolating betwixt vertices).
 
        -wire   Wireframe.
 
        -nowater
                Do not display 'water' (forces negative  values  to  zero,  and
                selects a different coloring method).
 
        -visibility float
                Value in range [0.2,1.0] (default 0.6) specifying proportion of
                viewable XY plane which is to be drawn upon.
 
        -color string
                Selects color scheme.  Use with no or bogus argument  for  cur-
                rent list.
 
        -nsubdivs integer
                Number  of times to recursively subdivide each triangular tile.
                Each increment increases total triangles by a factor of 4;  for
                instance  the  default  setting  4 results in 256 triangles per
                tile.
 

ENVIRONMENT

        DISPLAY to get the default host and display number.
 
        XENVIRONMENT
                to get the name of a resource file that  overrides  the  global
                resources stored in the RESOURCE_MANAGER property.
        X(1), xscreensaver(1)
 

COPYRIGHT

        Copyright  (C)  2005 by Matus Telgarsky.  Permission to use, copy, mod-
        ify, distribute, and sell this software and its documentation  for  any
        purpose  is  hereby  granted without fee, provided that the above copy-
        right notice appear in all copies and that both that  copyright  notice
        and this permission notice appear in supporting documentation.  No rep-
        resentations are made about the suitability of this  software  for  any
        purpose.  It is provided "as is" without express or implied warranty.
 

AUTHOR

        Matus Telgarsky <catachresis@cmu.edu>, 2005.