Aligning particles to a processed image

In this recipe, we will show how you can use techniques you were introduced to in the previous recipes to make particles align to the edge detected in the image.

Getting ready

In this recipe, we are going to use the particles' implementation from the Creating a particle system in 2D recipe; the image processing example from the Detecting edges recipe in Chapter 3, Using Image Processing Techniques; as well as simulating repulsion covered in the Applying repulsion and attraction forces recipe.

How to do it…

We will create particles aligning to the detected edges in the image. Perform the following steps to do so:

1. Add an anchor property to the Particle class in the Particle.h file.

   ci::Vec2f anchor;

2. Set the anchor value at the end of the Particle class constructor in the Particle.cpp source file.

   anchor = position;

3. Add a new property to your application's main class.

   float maxAlignSpeed;

4. At the end of the setup method, after image processing, add new particles...