Creating a flow field with Perlin noise

In this recipe we will learn how we can animate objects using a flow field. Our flow field will be a two-dimensional grid of velocity vectors that will influence how objects move.

We will also animate the flow field using vectors calculated with Perlin noise.

Getting ready

Include the necessary files to work with OpenGL graphics, Perlin noise, random numbers, and Cinder's math utilities.

#include "cinder/gl/gl.h"
#include "cinder/Perlin.h"
#include "cinder/Rand.h"
#include "cinder/CinderMath.h"

Also, add the following useful using statements:

using namespace ci;
using namespace ci::app;
using namespace std;

How to do it…

We will create an animation using the flow field. Perform the following steps to do so:

1. We will begin by creating a Follower class to define the objects that will be influenced by the flow field.

   Declare the following class before the main application class:

   class Follower{
   public:
    Follower( const Vec2f& pos ){
     this->pos = pos;
    }
   ...