ImportAlias addon for Blender

Converts Alias NURBS data into meshes and imports it into Blender.

The following datasets are converted.

• NURBS Surface: Meshes
• NURBS Curves: NURBS Curves
• Subdivision: subdiv for ImportAlias_2023 version.
• Shaders: Materials
• Layers: Collections

from Alias

To Blender

Requirements:

• OS: Windows 10 64bit with VC++ runtime 2019 or above.
• Alias: Alias 2023 or newer should be installed. (download the legacy version of the addon, for older versions)
• Blender: Blender 3.0.0 or newer.

Installation:

Install the downloaded addon using Edit->Preferences->Install and choos the downloaded ZIP file. Do not unzip the file prior to installation. Please uninstall and remove the older addon, before installing the latest version.

Usage:

The menu is installed under

File-> Import-> Alias

Import Options:

• Meshes: Imports Alias mesh data (default: off)
• Curves: Imports Alias Curves as Blender NURBS curve (default: off)
• Subdivs: (only available in ImportAlias_2023 version) (default: on)
• Tolerance: Lower values gives you finer mesh (slower as well). (default=0.01)
• Autoflip Normals: Automatically flip the mesh normals to point outwards. (default: off)
• Merge meshes: Joins the meshes in the collections to a single mesh (default: off)

Limitations:

• The Autoflip normals options attempts to make the mesh normals consistant to point outward and might not correct all the normals. Ideally the surface normals should be checked and corrected in Alias.
• In Autodesk Alias 2023 a new adjust crease functionality was introduced and is not compatible with general subdivision algorithms. Such creases, will be transfered as constant creases. Switch on the mesh Autosmooth option, for the creases to appear sharp. (GPU acceleration for subd will be switched off in that case).

Release history

v 1.0.0:

• Initial release.

v 1.1.0:

• Added Support for subdivision creases.
• Added support for auto flip normals

v 1..3.0

• Added Support for Construction Entities.

v.1.3.1

• Bug Fix for ImportAlias_2023, SUBD Mirror bug.

v.1.4.0

• Support for Blender 4.0

v.1.4.5

• Bug Fix for ImportAlias_2023: Materials for SubD was not getting asssigned.

v 1.5.0

• Support for Blender 4.1

v 1.6.0

• Support for Rational Curves
• Support for Blender 4.1 (legacy version)

v 1.7.0

• Bug Fix: Crash while importing geometry that fails to tesselate.

v 1.8.0

• Bug Fix: Automatically trim very long Layer/Object/Shader names and other minor fixes.

v 1.9.0

• Enhancenment: Support for Blender Extension

ImportAlias_2023.zip: For Alias versions newer than 2023

ImportAlias.zip: For Alias versions older than 2023.