Game Notes

Your Alias software package includes several tools to allow you to use Alias for 3D game and interactive media creation.

This section covers:

Game Tools

During the installation of Alias, the Game Tools programs and libraries are also installed. This includes the Direct Translators (Dt) and OpenAlias/Model translators.

The game tools are found under /usr/aw/alias/ODS/Games. The plug-ins and program should be runable from this location. Source code is provided for these game tools in the ODS/Games/source directory.

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Note: Authorization from game platform vendors is required for access to specific platform translators. Playstation and Sega Saturn developers should obtain the translators from the respective on-line support sites.
To install individual translators, there is a UNIX shell script, InstallGame, which is run to unpack the translators and place the files in the required locations. Instructions for specific platform translators are included with the file downloaded from the platform manufacturer's site.
For a simple install, type the following:
/usr/aw/alias/ODS/Games/bin/InstallGame
The appropriate translators will be enabled.

Two types of translators are available:

  • DT based translators
The DT based translators implemented as loadable modules to the plug-in mgame. They are not themselves Alias plug-ins, and cannot be loaded with the Plug-in Manager utility. The mgame plug-in can be launched from the Alias Utilities menu. You can also run the translators from the command line with the DtExport standalone program.
  • OpenAlias based translators
Alias's Older Sega Saturn and generic Real Time Game (RTG) format translators are implemented as OpenAlias or OpenModel plug-ins, and once installed are available from the Alias menus. These translators now have newer Dt based versions.

Polygon Plug-in Tools

Of particular interest to Game and Interactive Media developers are several polygonal modeling plug-ins included with your Alias package.

These tools can be found in the /usr/aw/alias/ODS/OpenAlias/examples directory and provide several powerful beveling, rounding, and subdivision tools for polysets.

These tools are provided as examples of plug-in functionality that may be added to your Alias product and are not supported.

Existing Limitations

Limitation

Alias and reversed polygon normals.

Alias's rendering technology is designed to work best with polygonal surfaces that have a continuous normal orientation, and polygons with less than five vertices.

This means that a single polygon in the middle of a polygonal object with a reversed normal may lead to some odd shading artifacts. In order to correct this, use the Polygon Edit > Polyset > Extract polygons tool to place the reversed polygons in a separate polyset, or reverse its normal using the Polygon Edit > Normals > Flip tools.

Workaround

You may find that you achieve best results when dealing with reversed normals and polygons with greater than 4 vertices using the toggle shade function with Fast Options set to OFF ( Display > Tgl shade-) .

Limitation

Face to Polygon conversion.

When applied to faces, the Create Polygons tool (Polygons > Create polygons) uses the Uniform Along U subdivision value in the Spline Surface to Polygons window to determine the level of subdivision for the face, regardless of what the Subdivision Type is set to.

Limitation

Polygon Edit > Polygon reduction does not with polysets only selected.

The Polygon reduction tool requires that you select the vertices of polysets. Selecting the polysets themselves will not work correctly.

Limitation

The Dt parsing for textures does not support solid textures.

Limitation

Changed mouse button to pick polygon behavior for Version 8.

As of Version 8, the following items require that you use Shift-Right mouse button instead of simply using the right mouse button for pick operations in the polygon tools: Pick > Vertex, Pick > Polyset, Vertex split/merge, Polyset combine/extract, Polyset cleanup, Texmap, Polygon reduction, Convert, and Explode.

Limitation

axe and axinfo produce fatal errors under game circumstances.

Workaround

You must have TCL installed from the SGI distribution disk, and have libtcl.so in your LD_LIBRARY_PATH in order to use the aXe editor provided with Alias.



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