README.md

libspaceturtle

Libspaceturtle is a small n-body simulation program that has both 2d and 3d particle particle integration methods, as well as a two dimensional version of the Barnes-Hut Tree Code algorithim.

Building

As of yet there are no dependencies, to build the library simply run make in the main directory and make install to install it.

If you want to see a quick preview run make test, and ./test, this will use both 2d methods to simulate a 10kg body in an orbit similar to that of the ISS.

Usage

All of the solvers operate on a linked list of bodies (type struct body), create your root node by running: i

struct body * root = add_body(xposition, yposition, xvelocity, yvelocity, mass, radius, NULL, NULL, NULL); // Units are kg, m, s

You can then add further bodies to that list like so:

add_body(xposition, yposition, xvelocity, yvelocity, mass, radius, NULL, NULL, root);
/* the first pointer can be a pointer to an attribute your application requires,
the second can be a pointer to a parent body making position and velocity an offset from that body */

To run the simulation pick a solver and do the following:

struct world_config system;
system.tickspersec; // specifys the number of ticks in a second
// add _tctd to use the Barnes-Hut method
step_forward(root, system, 1000); // this runs the simulation forward 1000 ticks;

In order to access the results simply read the variables xpos, ypos, xvel, and yvel from the body struct.