Buoyancy Force

Introduction

In this new version of Miarmy, we can make some specific geometries as buoyancy mesh.

Any agent enabled dynamics can interactive with them and get the result of floating on the water.

In addition, we added drag force, draught force and offset for making the result more natural

Buoyancy under the hood

The buoyancy system has 2 parts:

• Buoyancy: the force is measured by the volume of object in water
• Drag force Damping: the drag force in water is huge so that the character cannot bounce out from the water

Workflow

• Mark specific polygon mesh as buoyancy kinematic primitive
  Miarmy > Physics > Kinematic Primitves > Mark Buoyancy Mesh

_{any mesh can be marked as buoyancy mesh, there is a green bounding box around it after marking}

• Then, any agents enable dynamics simulation can interactive with it.

_{dynamics agents interactive with buoyancy mesh}

• We can also tweak the buoyancy force, in Miarmy > Physics Global or tool shelf . 
  This controls how big the force push the agents up in water.

_{The buoyancy parameters}

• The fluid damping controls the drag force in water, limited the body move speed in water, avoiding the water push agent out from water too high

• Also we can tweak the draught offset for adjusting the agent float relatively higher or lower than the real water-mesh surface

_{offset examples}