boidsServ

A C.W.Reynolds boid's implementation in C++ with realtime controls.

The end goal is to provide an indpendant process capable of taking inputs (both for controls and querry), and outputing various informations about the boids in return.

Controls

Currently, only four keyboard inputs are used as realtime-controls:

• [A] Create a new flock off boids. Number and position are randoms, with numbers between 50 ans 500.
• [S] Delete the mmost recently created flock.
• [Q] Exit the program.
• [SPACE] Allow/block the Sky from being updated

On input, the Scene object will call the function setup by the Scene::setInputFnct() hook. Change it to change controls (except [Q], currently hard-coded). Scene::setInputFnct() need to be passed a pointeur to a function with this prototype:

void  inputExample(void *arg, int key);

When called, this function will received the arg pointer setup by the hook, and the key symbol, as defined by the "KeyCode" field by the SDL. See more

You can also defined a function to be called at each new cycle, with this kind of prototype:

void  loopExample(void* arg);

This is done using the Scene::setLoopFnct() hook. This is mainly used to gather informations about the current state of the simulation/act upon it. It might later gain an option to only be called once ever N cycle. We'll see.

Dependecies

• SLD2 is used for all video rendering, and input management.
• CPTL is used for threadPooling (but is already included in the code as a header).
• STK is used to managed everything sound related.

Structure and how to use

The Sky class need to be instancied only once. It will manages all the flocks of boids. Each Flock class holds N boids. Currently, each Flock just ignore each other, but that will change in the future.

                  +-----+                       +-------+
                  | SKY |-------------------+   | SCENE |
                  +-----+                   |   +-------+
                     |                      |       |
       +-------------+-------------+        |   +-------+
       |             |             |        +-->|  SDL  |
  +---------+   +---------+   +---------+       |RENDER |
  | Flock 1 |   | Flock 2 |   | Flock 3 |       +-------+
  +---------+   +---------+   +---------+
    |             |             |
    +-[Boid1]     +-[Boid1]     +-[Boid1]
    +-[Boid2]     +-[Boid2]     +-[Boid2]
    +-[Boid3]     +-[Boid3]     +-[Boid3]
    +-[Boid4]     +-[Boid4]     +-[Boid4]  

Exemple main.cpp

First thing needed is an instance of a Scene object (and only one !). If the constructor is givent a configuration file as parameter, it will try and use it as settings. Otherwise, default values are used. You can then create a Sky object, and add/remove flocks to it as you see fit. Then, using Scene::mainLoop(Sky& sky), launch you simulation. To modify controls, look at Scene::mainLoop() again.

#include "Scene.hpp"
#include "Sky.hpp"

int main(void)
{
  //Create a new Scene, using .conf as a config file. Must be done first.
  Scene sc(".conf");

  //Create a new Sky, which will hold ours Flocks of Boids.
  Sky sky;

  //Add a Flock of 500 Basic Boids (of random color) to our sky.
  sky.addFlock(500);

  //Add a Flock of 50 Predator green Boids
  sky.addFlock(50, "Predator", 0, 255, 0);

  //Apply a new RuleSet to the last Flock of the Sky (aka the predator's one).
  sky[-1].setRuleset(RuleSet(0.01, 0.1, 0.1, 1.0, 15.0, 30.0, 5.0));

  //Finally, launch the simulation.
  sc.mainLoop(sky);

  return 0;
}

TODO next

• Get a better visual for the boids.
• Create more different type of boids with differents ruleset
• Create a proper control system (might be either via a GUI or a command prompt)