Courtesy of Listratov Konstantin

Maxwell 4 includes extensions, specific external pieces of code which extend the capabilities of Maxwell.

The extensions are .mxx files (stands for Maxwell Extensions) and are located in the Maxwell 4>extensions folder.

There are several types of extensions in Maxwell 4:

Geometry Loaders: the extension code generates a new object in the scene with particular characteristics (like Maxwell Sea, Volumetric or the Alembic importer)
Object Modifiers: the extension modifies an existing geometric object (like the Grass, Scatter or Subdivision modifiers).
Procedural Geometry: the extension renders geometry based on a mathematical description.
Procedural Textures: provide textures based on mathematical description, not on bitmaps.
Material Modifiers: these extensions provide a simplified user interface for some material types.
Camera Lens Extensions: with these extensions the user can program customized lens types, such as stereo, fish-lens...
BRDF Extensions: these extensions implement BRDF's, which can be analytical, data driven or in-between.

The current available extensions and the features they provide are:

Geometry Loaders

Extension name	What it does	More info...
AssetReference.mxx	Loads geometry from a variety of file formats.	Asset Reference
MaxwellSea.mxx	Creates a simulation of the ocean surface based on the Tessendorf model.	Maxwell Sea
MaxwellMesher.mxx	Renders particles from RealFlow™, meshing the particles at render time. Meant for rendering fluids and provides sophisticated controls over the resulting fluid mesh.	Maxwell Mesher
RFMeshes.mxx	Render fluid meshes from RealFlow™ that have already been meshed in RealFlow™.	RF Meshes
RWMeshes.mxx	Allows Maxwell to render RealWave water simulation meshes already created in RealFlow™.	RW Meshes
MWObjectAlembic.mxx	Imports objects in Alembic format.	Alembic support

Object Modifiers

Extension name	What it does	More info...
MaxwellCloner.mxx	Allows Maxwell to distribute instances of an object using a particle cloud file.	Maxwell Cloner
MaxwellGrass.mxx	The grass generator. Generates and distributes random grass guides over the object surface following certain user parameters.	Maxwell Grass
MaxwellScatter.mxx	Scatters instances of a given object across the surface of another object.	Maxwell Scatter
SubdivisionModifier.mxx	Subdivides the object using Pixar™ subdivision algorithms: Loop and Catmull-Clark.	Pixar™ OpenSubdiv

Procedural Geometry

Extension name	What it does	More info...
MaxwellVolumetric.mxx	Creates a volumetric media either as a constant density object, using particle files to create smoke, fog, atmospheric haze etc or loading a OpenVDB file.	Maxwell Volumetric
MaxwellParticles.mxx	Renders particles from RealFlow™ or other particle systems as spheres.	Maxwell Particles
MaxwellHair.mxx MGrassH.mxx MGrassP.mxx	These three extensions have no visible user interface. They implement the rendering primitives used by hair and fur packages in 3D platforms or MaxwellGrass	Hair Maxwell Grass

Extension name

What it does

More info...

MaxwellVolumetric.mxx

Creates a volumetric media either as a constant density object, using particle files to create smoke, fog, atmospheric haze etc or loading a OpenVDB file.

Maxwell Volumetric

MaxwellParticles.mxx

Renders particles from RealFlow™ or other particle systems as spheres.

Maxwell Particles

MaxwellHair.mxx

MGrassH.mxx

MGrassP.mxx

These three extensions have no visible user interface. They implement the rendering primitives used by hair and fur packages in 3D platforms or MaxwellGrass

Hair

Maxwell Grass

Procedural Textures

Extension name	What it does	More info...
MaxwellProcedurals.mxx	A bunch of the typical procedural textures found on several 3D platforms: checker, circle, grid, gradient, noise, marble, voronoi, etc...	Procedural Textures
TiledTexture.mxx	This extension allows the use of tiled textures following the UDIM file naming convention.	Texture Mapping: UV and UDIM
WireframeTexture.mxx	Renders triangle edges with a different color.	Wireframe

Extension name

What it does

More info...

MaxwellProcedurals.mxx

A bunch of the typical procedural textures found on several 3D platforms: checker, circle, grid, gradient, noise, marble, voronoi, etc...

Procedural Textures

TiledTexture.mxx

This extension allows the use of tiled textures following the UDIM file naming convention.

Texture Mapping: UV and UDIM

WireframeTexture.mxx

Renders triangle edges with a different color.

Wireframe

Material Modifiers

Extension name	What it does	More info...
MaterialModifiers.mxx	These extensions provide a simplified user interface for some material types. Current types are: Lambert, AGS, Opaque, Transparent, Metal, Translucent, Car Paint, Hair.	Material Assistants

Camera Lens Extensions

Extension name	What it does	More info...
CameraLensExtensions.mxx	These extensions implement Lat-Long Stereo Lens and Fish-Eye Stereo Lens	Camera Lenses

BRDF Extensions

Extension name	What it does	More info...
TableBRDF.mxx	Implements reading of MERL™ BRDF Database materials.	MERL Material (TableBRDF)
XriteBRDF.mxx	Implements reading of X-Rite™'s AxF™, Appearance Exchange Format materials.	X-Rite AxF Material

Extension name

What it does

More info...

TableBRDF.mxx

Implements reading of MERL™ BRDF Database materials.

MERL Material (TableBRDF)

XriteBRDF.mxx

Implements reading of X-Rite™'s AxF™, Appearance Exchange Format materials.

X-Rite AxF Material

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