MayaPhysx Documentation

MayaPhysx plugin for Autodesk Maya 2011 x86.

Download URL: https://code.google.com/p/maya-physx/downloads/list

Why do develop MayaPhysx?

MayaPhysx plugin has been developed as a personal project, with a purely educational intent which

seeks to understand and learn the Maya API and the PhysX SDK.

How was MayaPhysx develop?

MayaPhysx was initially developed as an implementation of the Nvidia PhysX's SDK samples in

Autodesk Maya. These examples are only available on NVIDIA PhysX Rigid Bodies.

Access to MayaPhysx plugin functionality currently only available under MEL commands.

Which software was used?

To develop the program, the following software was used:

- Autodesk Maya 2011 Educative Version.

- Visual Studio 2008 Express Editions.

- NVIDIA PhysX SDK v2.8.4_win.

MayaPhysx Commands, usage and explanation

MayaPhysx requires the creation of two key nodes in a specific order, MPhysxLocator and

MPhysxScene.

For the plugin initialization you must run the following commands in a Autodesk Maya MEL window:

createNode MPhysxLocator -n MPhysxLocator1;

createNode MPhysxScene -n MphysxScene1;

addAttr -dt "string" -ln "physxMsg" -h true;

expression -string "MphysxSimulateCMD";

By default the gravity of the scene is X=0, Y=-9.8, Z=0. After creating the node MPhysxScene, you

can change the gravity with the following attributes “In Xgravity”, “In Ygravity”, “In Zgravity” :

In MayaPhysx you can create the following rigid objects:

- Ground Plane

- Box

- Sphere

- Convex Mesh

- Triangle Mesh

GroundPlane:

command (MEL)

PhysxCMD -groundPlane;

Synopsis

PhysxCMD -groundPlane is not undoable, queryable, and editable.

This command creates a plane of infinite dimensions in X y Z in the global position (0, 0, 0). It is

useful to create a solid ground on which to perform the simulations. This command does not create

visible objects in the Maya viewport.

Box

command(MEL)

PhysxCMD -box;

Synopsis

PhysxCMD -box is not undoable, queryable, and editable.

This command creates a physical box based on the size of the currently selected object.

Flags

Long name Description Argument type

-ad float

This flag specifies the Angular Damping

which will be created with the physical object

-d float

This flag specifies the Density with

which will create the physical object. If not

density is specified the object will be static.

-ka void

This flag specifies that the object will be

created as a Kinematic Actor (only activated

by contact with a dynamic actor).

-f float float float

This flag specifies the initial force applied to the

object in the X, Y, Z, coordinates at the

simulation start.

Sphere

command(MEL)

PhysxCMD -sphere;

Synopsis.

PhysxCMD -sphere is not undoable, queryable, and editable.

This command creates a phisical sphere based on the height of the current selected object

Flags

Long name Description Argument type

-ad float

This flag specifies the Angular Damping

which will be created with the physical object

-d float

This flag specifies the Density with

which will create the physical object. If not

density is specified the object will be static.

-ka void

This flag specifies that the object will be

created as a Kinematic Actor (only activated

by contact with a dynamic actor).

-f float float float

This flag specifies the initial force applied to the

object in the X, Y, Z, coordinates at the

simulation start.

Convex Mesh

command(MEL)

PhysxCMD -convex;

Synopsis.

PhysxCMD -convex is not undoable, queryable, and editable.

This command creates a physical convex based on the polygons of the currently selected object,

especially useful for a bit more complex forms than boxes or spheres.

NOTES:

- The object must not be more than 256 polygons.

- The command execution will triangulate the selected objects.

- The physical representation of the object will be automatically calculated as a convex shape,

ie, no concavity is taken into account during the simulation.

Flags

Long name Description Argument type

-ad float

This flag specifies the Angular Damping

which will be created with the physical object

-d float

This flag specifies the Density with

which will create the physical object. If not

density is specified the object will be static.

-ka void

This flag specifies that the object will be

created as a Kinematic Actor (only activated

by contact with a dynamic actor).

-f float float float

This flag specifies the initial force applied to the

object in the X, Y, Z, coordinates at the

simulation start.

Triangle Mesh

command(MEL)

PhysxCMD -triangle;

Synopsis.

PhysxCMD -triangle is not undoable, queryable, and editable.

This command creates a phisical trianble mesh based on the polygons of the current selected object,

especially convenient for creation of terrains and complex shapes.

NOTA:

- The Triangle Mesh objects are static, ie can not be moved, rotated and scaled. Any

animation created in the selected object will not be reflected in the physical simulation.

- The command execution will triangulate the selected objects.

Phisical Materials

command(MEL)

PhysxCMD -material;

Synopsis.

PhysxCMD -material is not undoable, queryable, and editable.

When you create any physical object, by default these have assigned a material with a restitution, static

friction and dynamic friction of 0.5.

To create an object with your self material specifications, run the command PhysxCMD -material

followed by the physical object command creation.

Flags

Long name Description Argument type

-r float

This flag specifes the Restitution

-sf float

This flag specifes the Static Friction

-df float

This flag specifes the Dynamic Friction

Bake Simulation

command(MEL)

PhysxCMD -bake;

Synopsis.

PhysxCMD -bake, bakes the simulation for the current selected objects.

NOTA:

- Before you start previewing the simulation you must “set key” the positions and

orientations at the first frame in your time line, for the physical objects. For previewing

the simulation just push play in the animation controls.

PhysxCMD usage samles.

//MayaPhysx initialization

createNode MPhysxLocator -n MPhysxLocator1;

createNode MPhysxScene -n MPhysxScene1;

addAttr -dt "string" -ln "physxMsg" -h true;

expression -string "MphysxSimulateCMD";

//Create a floor for our simulation

PhysxCMD -groundPlane;

//Create a dynamic cube width an angular damping of 0.5 and density of 10.0

PhysxCMD -box -ad 0.5 -d 10.0;

//Create a static cube

PhysxCMD -box;

//Create a Kinematic cube

PhysxCMD -box -ad 0.5 -d 10.0 -ka;

//Create a sphere width an initial force of X = 10000.0 , Y = 0, Z = 0.

PhysxCMD -box -ad 0.5 -d 10.0 -f 10000.0 0 0;

//Create a Convex width a material width a restitution of 0.9, static friction of 0.4 and a

//dynamic friction of 0.5

PhysxCMD -material -r 0.9 -sf 0.4 -df 0.5;

PhysxCMD -convex -ad 0.5 -d 10.0;

PhysxCMD -bake;