Person Atom Joint Physics Tab
”Select Root” Is a quick shortcut available on all Person Joints to take you to the Person Atom Root Control node.
VaM Atoms are made of two significant parts. The Atom Control and The Physics Object. The “Atom Control” (Green Square) is the node that you select and gives you access to all of the Atom’s control settings. The “Physics Object” (Circled In White) is the physical object that you interact with in VaM. When working with any of the physics settings for Atoms they are only affecting the Physics Object and not the Atom Control. In essence the majority of the settings in the Physics panels change the way the Physics Object interacts with its Atom Control. You are encouraged to set up simple tests such as the examples shown to become familiar with how Atom Physics work inside VaM.
“Spring” refers to the force connecting the Physics Object with its Atom Control. The higher the spring the more force needs to be applied to the Physics Object to move it away from its Atom Control.
”Hold Position Spring” This changes the amount of force connecting the Physics Object and it’s Atom Control. Setting this to “0” will cause the Physics Object to not follow the position of the Atom Control and drop to the floor. Setting this higher increases the tension of the physics spring between the two causing the Physics Object to closely follow it’s Atom Control.
In the above example: The Cone Atom is Parent Linked to the Cylinder Atom which is being animated by a motion capture. The Mass (
Atom Physics Object ) of the Cone Atom is set to 10 and the Hold Position Damper is set to 0. The Cone Atom’s Hold Position Spring is set to 3 different settings in this demonstration, from Left to Right: 1,000, 5,000 (Default) and 10,000. Notice on the Left how loose the Physics Object is from it’s Atom Control compared to how closely it follows it on the right. Setting this higher than 10,000 will increasingly tighten the spring between the two.
”Hold Rotation Spring” affects how closely the rotation values of the Physics Object follow the rotation values of it’s Atom Control node. The lower the number the looser the connection causing the Physics Object to swing wildly around. Increasing the tension will tighten how closely the rotation values of the Physics Object follows it’s Atom Control.
In the above example: The Cone Atom is Parent Linked to the Cylinder Atom which is being animated by a motion capture. The Mass (
Atom Physics Object ) of the Cone Atom is set to 10 and the Hold Rotation Damper is set to 0. The Cone Atom’s Hold Rotation Spring is set to three different settings, from Left to Right: 0, 100(default) and 1000. Again notice how closely the rotation of the Physics Object will follow it’s Atom Control as the spring is increased.
“Damper” refers to how the spring force proportionally reacts to the relative speed between the Physics Object and the Atom Control. In other words as the damper is increased the position or rotation values of the Physics object are smoothed and softened as it follows the Atom Control. As the value is lowered the more chaotic and energetic the Physics Object reacts.
”Hold Position Damper”
In this example the cone has a Mass of “10”, and the Hold Position Spring is set to 1,000”. On the left side of the gif the Cone has it’s Hold Position Damper set to “0” causing it to swing wildly around it’s Atom Control. On the right side of the Gif the Hold Position Damper is set to “100” causing the cone to follow it’s Atom Control much more gently and smoothly.
”Hold Rotation Damper”
In this example the cone has a Mass of “10”, and the Hold Position Spring is set to “10,000”. On the left the Hold Rotation Damper is set to “0” causing the Cone to swing wildly around. On the RIght the Hold Rotation Damper is set to “5” causing it to swing much gentler like a heavy bell.
“Force” in VaM refers to how much the mass of a Physics Object is affected by the acceleration of that Physics Object. Meaning the higher the mass of the Physics Object is, the more Force is required to separate that object from its Atom Control. This is similar to Spring but different in that it relates to how it reacts to outside forces such as gravity and motion and not to its connection to the Atom Control.
”Hold Position Max Force” Adjusts the amount of outside force required to separate the position of the Physics Object from its Atom Control.
In the above example the Cone again has a Mass of 10, On the left the Hold Position Max Force is set to 1,000. Consequently the cone is swung far out from it’s Atom Control. On the right the Hold Position Max Force is set to 10,000 bringing the cone much closer to its Atom control.
”Hold Rotation Max Force” Adjust the amount an outside force has on the rotation of the Physics Object.
In this example Hold Position Spring = 10,000, Hold Rotation Spring = 1000, Hold Position Damper = 100, Hold Rotation Damper = 10 and Hold Position Max Force = 10,000
On the left Hold Rotation Max Force = 100 and on the right Hold Rotation Max Force = 1000. On the left hand side the rotation of the Cone is much more chaotic. The right hand side rotation around the Atom Control is a lot smoother.
Link pos/rot spring/damper/max force effects the joint that is created between the linked to object and the atom. These settings only matter if you use physical link. When physical link is set, a new spring joint is added the binds the 2 physics objects. The link parameters control all of that interaction. In this mode, the spring works on both objects. As an experiment, after physically linking an atom to another atom physics object (not the control), turn off the other atom control by setting pos/rot to Off. You will see that other atom is bound to the current atom by the link spring.
”Link Position Spring”
”Link Rotation Spring”
”Link Position Damper”
”Link Rotation Damper”
”Link Position Max Force”
”Link Rotation Max Torque”
”Max Velocity Enable” Toggling this on allows you to adjust the maximum velocity of the Physics Object. By default this is toggled “on”.
”Max Velocity” By default this is set to”10” Which translates to 10 meters per second. Lowering this slows down a Mesh Object’s speed. Increasing this speeds them up.
