Dominoes: Rigid Bodies with Friction

by Cody Thompson

Description

Rigid body boxes colliding with the floor and other boxes to create a dominoe toppling scene. An initial velocity is added to the 'starting' dominoe to start the effect.

Features

• Rigid body dynamics.
• Rigid body box collision with a ground plane.
• Rigid body box collision with other box rigid bodies.
• Adjustable camera.
• Rigid body fake friction to stop the motion of rigid bodies.

User Controls:

• MouseClickDrag : Rotate Camera
• MouseClickDrag + ctrl : Zoom Camera
• MouseClickDrag + shift : Move Camera
• ' ' : begin simulation
• 'p' : initialize starting velocity of the starting dominoes
• 'r' : fully resets the scene and all rigid bodies to their starting frame and velocity

Notes:

• The friction fully stops every rigid body.
• The timestep is 1e-2, causing it to simulate faster at the expense of the dominoes going into the floor.
• You must press space and then 'p' to begin the simulation with the dominoes falling

Examples

A line of dominoes, showing some going slightly beneath the floor.

A circle of dominoes, showing that blocks stop completely once they hit the floor fully.

A sine curve of dominoes, experimenting with trigonometry.

A face of dominoes, demonstrating multiple trigonometry techniques and high amount of simulated rigid bodies.

Sources

• Shinjiro Sueda - Created most of the back end code for the main cloth system, and he provided all used information on rigid body dynamics and fake friction.

Bugs / Unfinished Areas of this Project

• Boxes do not stop if they are at an angle touching other boxes due to how the implemented friction works, but the do stop eventually (completely on the floor).
• Unmoving boxes are still simulated and their new information is still calculated, thus less optimized but can still run the face simulation at a decent performance level.