Making our particles sound reactive
In this recipe we will pick on the previous particle system and add animations based on fast Fourier transform (FFT) analysis from an audio file.
The FFT analysis will return a list of values representing the amplitudes of several frequency windows. We will match each particle to a frequency window and use its value to animate the repulsion that each particle applies to all other particles.
This example uses Cinder's FFT processor, which is only available on Mac OS X.
Getting ready
We will be using the same particle system developed in the previous recipe, Creating a particle system in 2D. Create the Particle and ParticleSystem classes described in that recipe, and include the ParticleSystem.h file at the top of the application's source file.
How to do it…
Using values from the FFT analysis we will animate our particles. Perform the following steps to do so:
Declare a
ParticleSystemobject on your application's class and a variable to store the number of particles...
