Lightwave object

Title(s): LightWave object

Version ID: NewTek LightWave 3D Object File Format

Date released: Most recent format specs dated October 16, 1996

Date: 1990

Creator(s): NewTek

Contributor(s): Allen Hastings & Stuart Ferguson

Relationships:

• Previous Version(s): Inherited from Videoscape 3D and Aegis Modeler 3D on the Commodore Amiga, both circa. 1988.

• Contains: none

• Syntax Format(s): LightWave 3D objects are stored as IFF files with a FORM type of LWOB. A FORM LWOB must contain a PNTS chunk, a SRFS chunk, and a POLS chunk. There may be zero or more SURF chunks anywhere in the file and up to one CRVS chunk. The POLS and CRVS chunks must be preceded by the PNTS chunk and the SRFS chunk. LightWave 2.0 also has the ability to save and load surface descriptions as FORM LWOB files that contain only a SURF chunk. Details and further explanation found here: Lightwave 3D Object File Format, 11/28/1994

• Family Format(s): none

Description: LightWave 3D objects are stored on disk as 3D meshes consistsing of points, polygons (which can be faces, curves or patches), and surfaces. Files can contain a single connected mesh or several disjoint meshes describing a single logical object. An object file may also contain one or more surface definitions with no mesh.

History: A detailed account, from 1988 to 2009: LightWave History.

Example(s): Detailed object file example found here: LightWave Object File Example

Identifier: none.

Documentation: Documentation Template Documentation found here: LightWave Object File Format

File Extensions: .lwo

Applications: NewTek LightWave 3D

• Native application(s): Engineering Format Application Template - Applications which are primarily designed to specifically run this engineering format.

• Interoperable applications: Engineering Format Application Template - Applications which can read or write files of this format, but are not native applications for the format.

Magic numbers: n/a

Format(s): image/x-lw

Rights: Proprietary license

Sustainability Factors: n/a

• Standardization: n/a

• Adoption: n/a

• • Licensing and patent claims: n/a

• Self-documentation: n/a

• External dependencies: n/a

• Technical protection considerations: n/a

Typical use: 3D Design

File classification:

• Type {Binary, Text}: Binary
• Raster data:
  • Raster data 2D:
    • Is Supported: true
    • Description:
  • Raster data 3D:
    • Is Supported: true
    • Description:
• Geometric representation:
  • Implicit representation:
    • Implicit surfaces:
      • Is Supported: true
      • Description: The SRFS chunk contains a list of the names of all the surfaces in an object (note that in LightWave 3D terminology, the word "surface" is defined as a set of attributes that describe the color and shading characteristics of a group of polygons). Each surface name appears as a null-terminated character string. If the length of the string (including the null) is odd, an extra null byte is added. Surface names should be read from the file until as many bytes as the chunk size specifies have been read.

• • • Implicit curves:
      • Is Supported: true
      • Description: This chunk contains a list of all the spline curves in an object. Each entry consists of a short integer specifying the number of vertices in a curve followed by that many short integers specifying the vertices themselves in sequential order, followed by a short integer specifying which surface is used by the curve, followed by another short integer specifying bit-flags associated with the curve. If bit zero is set then the first point is a continuity control point, and if bit one is set then the last point is. The point and surface indices are as they are in the POLS chunk, except that curves cannot have details. Curves should be read from the file until as many bytes as the chunk size specifies have been read.

• • • Point set:
      • Is Supported: true
      • Description: The PNTS chunk contains a list of the X, Y, and Z coordinates of all the points in an object. Each coordinate is stored as a four byte floating point number in IEEE format. Therefore, the number of

 points in an object can be determined by dividing the size in bytes of the PNTS chunk by 12.

• • Mesh:
    • Manifold surface meshes:
      • Is Supported: false
      • Description:
    • Manifold volume meshes:
      • Is Supported: false
      • Description:
    • Non-manifold meshes:
      • Is Supported: false
      • Description:
  • Parametric representation:
    • Parametric surfaces:
      • Is Supported: false
      • Description:
    • Parametric curves:
      • Is Supported: false
      • Description:
  • Contour sets:
    • Is Supported: false
    • Description:
  • NURBS:
    • Is Supported: false
    • Description:
• Multi-resolution models:
  • Is Supported: false
  • Description: false
• Dynamics: - Section describes whether or not the engineering format supports dynamics.
  • Kinematics: - Can the format support kinematics? Example: Does the format allow model parts to rotate?
    • Is Supported: - Is the feature supported in the engineering format?
    • Description: - This field is used to describe the support or lack of support of the feature.
  • Assembly: - Can the format support assembly? Example: Does the format allow the assembly instructions to be explicitly specified with a model?
    • Is Supported: - Is the feature supported in the engineering format?
    • Description: - This field is used to describe the support or lack of support of the feature.
  • Force(s): - Can the format support forces? Example: Does the format support acceleration forces?
    • Is Supported: - Is the feature supported in the engineering format?
    • Description: - This field is used to describe the support or lack of support of the feature.
• Boundary representation - Can the format support models with boundary representations?
  • Manifold surface boundary representations: - Can the format support manifold surface boundary representations? Example: The engineering format STEP
    • Is Supported: - Is the feature supported in the engineering format?
    • Description: - This field is used to describe the support or lack of support of the feature.
  • Manifold volume boundary representations: - Can the format support manifold volume boundary representations? Example: The engineering format STEP
    • Is Supported: - Is the feature supported in the engineering format?
    • Description: - This field is used to describe the support or lack of support of the feature.
  • Non-manifold boundary representations: - Can the format support non-manifold boundary representations? Example: The engineering format STEP
    • Is Supported: - Is the feature supported in the engineering format?
    • Description: - This field is used to describe the support or lack of support of the feature.
• Material transparency: - Can the format support transparency? Example: Does the format allow models to have a clear window in a car?
  • Is Supported: - Is the feature supported in the engineering format?
  • Description: - This field is used to describe the support or lack of support of the feature.

References: - A list of references regarding any aspects of this engineering format; any reading material supplemental to this page.