| Server IP : 127.0.0.2 / Your IP : 18.191.142.102 Web Server : Apache/2.4.18 (Ubuntu) System : User : www-data ( ) PHP Version : 7.0.33-0ubuntu0.16.04.16 Disable Function : disk_free_space,disk_total_space,diskfreespace,dl,exec,fpaththru,getmyuid,getmypid,highlight_file,ignore_user_abord,leak,listen,link,opcache_get_configuration,opcache_get_status,passthru,pcntl_alarm,pcntl_fork,pcntl_waitpid,pcntl_wait,pcntl_wifexited,pcntl_wifstopped,pcntl_wifsignaled,pcntl_wexitstatus,pcntl_wtermsig,pcntl_wstopsig,pcntl_signal,pcntl_signal_dispatch,pcntl_get_last_error,pcntl_strerror,pcntl_sigprocmask,pcntl_sigwaitinfo,pcntl_sigtimedwait,pcntl_exec,pcntl_getpriority,pcntl_setpriority,php_uname,phpinfo,posix_ctermid,posix_getcwd,posix_getegid,posix_geteuid,posix_getgid,posix_getgrgid,posix_getgrnam,posix_getgroups,posix_getlogin,posix_getpgid,posix_getpgrp,posix_getpid,posix,_getppid,posix_getpwnam,posix_getpwuid,posix_getrlimit,posix_getsid,posix_getuid,posix_isatty,posix_kill,posix_mkfifo,posix_setegid,posix_seteuid,posix_setgid,posix_setpgid,posix_setsid,posix_setuid,posix_times,posix_ttyname,posix_uname,pclose,popen,proc_open,proc_close,proc_get_status,proc_nice,proc_terminate,shell_exec,source,show_source,system,virtual MySQL : OFF | cURL : ON | WGET : ON | Perl : ON | Python : ON | Sudo : ON | Pkexec : ON Directory : /usr/share/graphviz/lefty/ |
Upload File : |
load ('def.lefty');
definit ();
#
# initialize window data
#
canvas = defcanvas;
wrect = [0 = ['x' = 0; 'y' = 0;]; 1 = ['x' = 400; 'y' = 500;];];
setwidgetattr (canvas, ['window' = wrect;]);
sq = function (x) {
return x * x;
};
# data structures
#
length = 300;
center = ['x' = 200; 'y' = 250;];
radius = 2 * length / sqrt (12);
fractalangle = 0;
maxlevel = 2;
# drawing functions
#
# draw a Koch curve (a ``snowflake'' fractal)
#
# start with a triangle and keep replacing edges
# with the construct: _/\_
# until the recursion level reaches 'maxlevel'
#
fractal = function (level, length, angle) {
local nlength, newpenpos;
if (level >= maxlevel) {
newpenpos.x = penpos.x + length * cos (angle);
newpenpos.y = penpos.y + length * sin (angle);
line (canvas, null, penpos, newpenpos, ['color' = 1;]);
penpos = newpenpos;
return;
}
nlength = length / 3;
fractal (level + 1, nlength, angle);
fractal (level + 1, nlength, angle + 60);
fractal (level + 1, nlength, angle - 60);
fractal (level + 1, nlength, angle);
};
drawfractal = function () {
clear (canvas);
setpick (canvas, center, wrect);
penpos = [
'x' = center.x + cos (fractalangle + 210) * radius;
'y' = center.y + sin (fractalangle + 210) * radius;
];
fractal (0, length, fractalangle + 60);
fractal (0, length, fractalangle - 60);
fractal (0, length, fractalangle - 180);
remove ('penpos');
};
# editing functions
#
# transform the fractal.
#
# map point 'prevpoint' to point 'currpoint'
# with respect to the center of the fractal.
#
transformfractal = function (prevpoint, currpoint) {
local prevtan, currtan, prevradius, currradius;
prevtan = atan (prevpoint.y - center.y, prevpoint.x - center.x);
currtan = atan (currpoint.y - center.y, currpoint.x - center.x);
fractalangle = fractalangle + (currtan - prevtan);
prevradius = sqrt (
sq (prevpoint.y - center.y) + sq (prevpoint.x - center.x)
);
currradius = sqrt (
sq (currpoint.y - center.y) + sq (currpoint.x - center.x)
);
radius = radius / prevradius * currradius;
length = radius / 2 * sqrt (12);
};
# user interface functions
#
# bind changes to the fractal to user actions
#
leftup = function (data) {
transformfractal (data.ppos, data.pos);
drawfractal ();
};
dops = function () {
local s;
s = ['x' = 8 * 300; 'y' = 10.5 * 300;];
canvas = createwidget (-1, ['type' = 'ps'; 'size' = s;]);
setwidgetattr (canvas, ['window' = wrect;]);
drawfractal ();
destroywidget (canvas);
canvas=defcanvas;
};
transformfractal (['x' = 0; 'y' = 0;], ['x' = 0; 'y' = 0;]);
drawfractal ();