4

Sega GL

In This Section:

• Converting to Sega GL Files 52
• Using the Sega GL Translator 53
• Testing the Output 60

This section describes how to use the interface of the Sega Saturn-specific Direct Translator.

For information on how to run the translator, see Using the MakeGame Plug-in on page 7 and Using Translators from the Command Line on page 14.

Converting to Sega GL Files

Availability

The Sega plug-in and its documentation are available to Sega-certified developers only from the Sega Web site.

Sega GL Translator

Special Features

• Allows per-polygon texture pieces

• Optimized format for texture table

• Object melting converts all objects in the scene into one Sega GL object

• Outputs Sega GL source code

Limitations

• Cameras are not converted

• Lights are not converted

• Soft body (vertex) animation is not converted

Installing

To install the Sega GL translator:

1

Download SE and SE.1 from the Sega Web site to a temporary directory on your computer.

2

Run InstallGame with the following options:

• -a alias-directory (the directory where Alias is installed. If you do not include this option, InstallGame will look in $ALIAS_LOCATION).

• - e (tells InstallGame the files are not encrypted).

• - t target-dir (the directory where the files will be installed).

• -f source-dir (the source directory where the SE files are located).

Using the Sega GL Translator

When you run the translator from MakeGame, the Sega GL Translator window appears. Use this window to set the options described in this section, then click Start conversion to begin.

Translator Related Settings

This section is located in the left side of the Sega Translator window.

Feedback

Lets you control the amount of information provided during conversion.

Output

• DOS text - outputs Sega GL source code to a file using CR+LF as the line delimiter.

• UNIX text - outputs Sega GL source code to a file using LF as the line delimiter.

• Downloader - downloads the source code directly to a connected Sega Saturn.

Format

Chooses the version (2.0 or 3.0) of Sega GL source code the translator will generate.

PolyNormal Calc

• VertexNormal based - uses the normals provided by Alias.

• NEWELL's method - calculates new normals using Newell's method. Use this option if you have any problems with polygons seeming "flipped" after conversion.

Texture size

• Fixed - gives all output textures the same size. Choose the width and height using the minimum and maximum sliders located underneath the Texture size menu.

When Texture size is Fixed, the minimum and maximum sliders become locked together, allowing you to set a single fixed size.

• Auto calculation - scales the output textures to a best fit within minimum and maximum values. Specify these values using the sliders located underneath the Texture size menu.

Scale

The translator scales the whole model by this factor before converting it to Sega GL source code.

Operations

Melt Objects

Flattens the hierarchy of objects into one large Sega GL object.

Texture Tbl Optim.

Optimizes the texture table (do not repeat texture pieces).

Prelight Texture

Applies a simple pre-light operation to the textures. Currently this operation uses only the polygon normals.

Vertex Tbl Optim.

Optimizes the vertex table (do not repeat vertices at the exact same location). This option is only useful if Melt Objects is turned on.

Downloader Related Settings

This section appears when you choose Downloader from the Output pop-up menu.

Init Viewer

Click this button to reset the SCSI connection and download the monitor program to the connected Saturn CartDev.

Click this button when you turn on the Saturn, and want to reset the viewer.

SCSI Id

The SCSI identifier on the SGI side of the connection to the Saturn CartDev.

Start Frame and End Frame

Start and end frames of the animation to convert.

Target Data Addresses

These text boxes allow you to enter exact memory locations when downloading data to the Saturn.

Enter 0x00000000 for continuous memory allocation. Refer to the Saturn programming manuals for more information.

SGL Related Settings

This section is located at the top right of the Sega Translator window.

These options control standard Sega GL settings and modes. Refer to the Sega GL specifications for information.

File-Specific Settings

This section is located at the bottom of the Sega Translator window.

Use this section to enter filenames when you choose DOS text or UNIX text from the Output pop-up menu.

Model/Hierarchy filename

Filename for the file containing model and hierarchy information.

Use the Model and Hierarchy checkboxes to choose which information to include in the file (usually you will leave both options on).

Texture filename

Filename for the file containing texture information.

Use the Texture checkbox to choose whether to output texture information.

Light/Animation filename

Filename for the file containing lights and animation information.

Use the Lights and Animation checkboxes to choose which information to include in the file.

GetSegaGL Command Line Options

-v	(verbose) Print progress updates during the conversion.
-fs n	(frame start) Set n as the first frame of animation to output.
-fe n	(frame end) Set n as the last frame of animation to output.
-s factor	Scale the model by factor before converting.
-a	Do not output animation.
-n	Do not output MetaCycle information.

Alias Environment Variables

DT_EXPORT_DIR

The directory where exported files are created. This is the same as the Export directory field of the MakeGame window.

• Parameters - a valid path to a directory

• Default - '.' (the current working directory)

Output

The Sega translator's Sega GL source code output is flexible. The translator can output up to three files:

• A file containing the model and/or hierarchy. If you turn both the Model and Hierarchy checkboxes off, this file is not created.

• A file containing the textures. If you turn the Texture checkbox off, this file is not created.

• A file containing the lights and/or animation. If you turn both the Lights and Animation checkboxes off, this file is not created.

Testing the Output

Before you Begin

1

Set up the development Saturn and CartDev according to their instructions.

2

Make sure the SCSI ID dial on the back of the CartDev matches the SCSI ID text box (in the Downloader related settings).

If you have problems with SCSI communications:

• Make sure the SGI SCSI ID's device (in the /dev/scsi directory) has write permission. Since only the root user can change the permissions, you may need to contact your system administrator.

• Change the CartDev SCSI ID dial and enter the new number in the SCSI ID text box (in the Downloader related settings).

• Shut down your workstation and restart it (contact your system administrator). When the workstation boots up again, it should find the CartDev as one of its SCSI devices.

Downloading to a Development Machine

1

Choose Downloader from the Output pop-up menu.

2

Click Init Viewer if you just switched on the Saturn, or if you want to reset the viewer.

3

Click Start conversion to convert the model to Sega GL and download it to the Saturn.

The following screen appears after the CartDev is initialized:

The following screen appears after the monitor program is downloaded:

The following screen appears after the Alias|Wavefront viewer program is downloaded:

Using the Sega GL Demo Viewer

Standard mode
Left/Right Top buttons	Change mode.
A+B	Toggle information display.
A+B+C	Clear screen.

Object Move, Object Rotate, Object Scale modes
X	Show previous object.
Y	Show next object.
B	Show current object.
C	Reset transformations.
Left, Right	Move/Rotate/Scale in X
Up, Down	Move/Rotate/Scale in Y
Z+Up, Z+Down	Move/Rotate/Scale in Z

Camera Move mode
B	Show current object.
C	Reset moves.
Left, Right	Move camera in X.
Up, Down	Move camera in Y.
Z+Up, Z+Down	Move camera in Z.

Camera Rotate mode
Start	Switch between Look at (LAT) and Direct (NLM) modes.
B	Show current object.
C	Reset rotations.

Camera Rotate/Look At mode
X	Look at previous object.
Y	Look at next object. (When there is no current object, look at the origin).
Left, Right	Change longitude.
Up, Down	Change longitude.
Z+Up, Z+Right	Rotate camera around the Z-axis.
Z+Up, Z+Down	Move camera away from/toward the current object.
A+Up, A+Down	Increase/decrease Y offset.

Camera Rotate/Direct mode
Left, Right	Rotate camera around the Y-axis.
Up, Down	Rotate camera around the X-axis.
Z+Up, Z+Right	Rotate camera around the Z-axis.