Thinking Particles Repulsion Bounce

Written by Panait Mihai

Saturday, 02 August 2008 23:01

Two groups of particles collide and get different colors.

Thinking Particles Operators used in this tutorial: (O) Particle Draw, (O) Geometry Instance, (O) Size, (O) Velocity, (O) Shape Material, (O) PPass, (O) PPass AB, (O) Standard Collision,(O) Repulsion Bounce, (C) Particle Age, (C) Standard Collision, (C) In Group, (C) Distance, (H) And.

(O) - Operator, (C) - Condition, (H) - Helper.

Download Video Tutorial and Project Files from the bottom of this page. Tutorial length: 26:00 min.

Thinking Particles 02 - Repulsion Bounce from Mihai Panait on Vimeo.

Group of particles colliding on a board.

To build this Thinking Particles Scene we need the following things.
A Sphere Object used as reference for the particles shape.
A board which will Not interact with the particles.
A Box Object named Deflector Box which will keep the particles on the Board.
This Box has a Normal Modifier applied to it with Flip Normals Enabled and is linked to a U-Deflector.
The U-Deflector has a bounce value of 1.2 and will be linked to a Thinking Particles Operator.
We also need five different colored materials.
Then the Thinking Particles System.

For this system we need two particle groups. One named Green And one named Blue.
In the Master Dynamic rollout we have six Dynamic Sets.

The first is Draw Green.
Contains a Particle Draw Operator. This will draw the green particles to the scene.
Geometry Instance Operator will assign the sphere shape to the particles.
Size Operator will set the size to 20 for the green particles.
Particle Age Condition will assign on Born Event a green Material to the particles.

The Second Dynamic Set is Draw Blue.
This will draw to the scene the blue particles. It has the same operators And Conditions like the Draw Green set, but instead of the green material will assign the blue one. It also has a Velocity Operator. This will give the initial impulse to the blue particles to move in the direction and with the speed you want.

The third Dynamic Set is Collision Border.
This will handle the collision between the particles and the Deflector Box. It also assigns the blue material to the Particles from the blue group, and green material for those from the green group. When the particles collide with each other they will get different colors. If the particles hit the border will get back their initial colors.

The forth Dynamic Set will handle the collision between the Blue and Green particles. If this happens will assign them the red material and with the Repulsion Bounce Operator will make them bounce. All this will happen if the distance between particle centers reaches a value of 21. Keep in mind that the particles size is 20.

The next two Dynamic Sets handle the collision between particles of the same type. If the Particles belong to the green group will get the orange material and if the particles belong to the blue group will get the purple material.
The collision is handled in the same way, with the Repulsion Bounce Operator.