Renderware
Note, this article discusses the 3D file format, not the 3D Render Engine. Nevertheless, parts of Renderware Engine core are currently still used by the Active Worlds Browser. The engine as well as the file format were developed by Criterion Software and has been owned by EA Games since 2004. EA Games closed the product line in 2007 for 3rd party developers, continuing using the render engine for some of their own game titles.
The browser uses the legacy ASCII version of Renderware scripts also besides other 3D file formats. ASCII means the file are in a human readable form. Such files require the use of the ".rwx" file extension (Rendware Exchange format). This allows for creation and editing of RWX objects using a text editor such as Notepad.
ActiveWorlds has extended the file format's definition with its own extensions. The format is suitable for simple models and for jointed avatar (depreciated) structures/hierarchies only. Alternatives: For skinned avatars Blender and the DX format (.x file extension) is recommended. TrueSpace .cob file formats are also still supported.
File structure
As an ASCII script file format, models are made up with various case-insensitive commands and options in a hierarchy, not unlike HTML or XML. No special characters are used to define sections, however for human readability clumps are typically indented with spaces or tabs. The following is an example of a simple RWX object that uses four verticies with UV definitions to make a centered wall:
- Note that ModelBegin and ModelEnd may be used at the top and bottom of the file, but are optional
ClumpBegin Surface 1 1 0 Texture tile1 TextureModes Lit Vertex -.2 0 0 UV 0 1 Vertex -.2 .4 0 UV 0 0 Vertex .2 0 0 UV 1 1 Vertex .2 .4 0 UV 1 0 Quad 2 1 3 4 ClumpEnd
| Script | Function |
|---|---|
| ClumpBegin | Begins definition of an object |
| Surface 1 1 0 | Shortcut for defining ambient, diffuse and specular respectively |
| Texture tile1 | Name of texture file used for textured surfaces. In this case, this makes use of the standard AlphaWorld tile1.jpg texture. |
| TextureModes Lit | Lighting mode of surfaces, of which only "Lit" is supported |
| Vertex -.2 0 0 UV 0 1 | First defined point in space with UV values |
| Vertex -.2 .4 0 UV 0 0 | Second defined point |
| Vertex .2 0 0 UV 1 1 | Third defined point |
| Vertex .2 .4 0 UV 1 0 | Fourth defined point |
| Quad 2 1 3 4 | Defines a quad surface to render, referencing the four above verticies by the order of definition |
| ClumpEnd | End of object definition |
Commands
Standard commands
This is a list of the standard RWX script commands that the browser uses to render Renderware models. Some may have unsupported or unused options, such as point-cloud rendering for GeometrySampling.
| Command | Function |
|---|---|
| # | Allows a comment to be placed within the Renderware file |
| AddMaterialMode | Adds the specified material mode to the current material modes |
| AddTextureMode | Adds the specified texture mode the the current texture modes |
| Ambient | Defines the amount that the polygons will be affected by ambient lighting |
| AxisAlignment | Defines if the object is to be a 'facer' |
| Block | Creates a block (Cube for example) |
| ClumpBegin | Declares the beginning of a clump |
| ClumpEnd | Defines the end of a clump |
| Collision | Determines if the object should be solid or not |
| Color | Defines the color of an objects polygons |
| Cone | Creates a cone |
| Cylinder | Creates a cylinder |
| Diffuse | Defines how the objects polygons will be affected by diffuse lighting |
| Disc | Creates a flat disc |
| GeometrySampling | Defines the geometry sampling mode of the current material |
| Hemisphere | Creates a hemisphere |
| Identity | Sets the current transformation matrix to the identity matrix |
| LightSampling | Defines how lighting should affect an object overall |
| MaterialBegin | Sets the beginning of a new material |
| MaterialMode | Defines the material mode of the current material |
| MaterialEnd | Sets the end of a material, to revert to a previous definition |
| ModelBegin | Defines the beginning of a model |
| ModelEnd | Defines the end of a model |
| Opacity | Sets the opacity (transparency) of the current material |
| Polygon | Creates a N sided polygon |
| ProtoBegin | Defines the start of a new prototype |
| ProtoEnd | Defines the end of a prototype |
| ProtoInstance | Calls upon a defined prototype |
| ProtoInstanceGeometry | Calls upon a defined prototype, ignoring it's materials |
| Quad | Creates a 4 sided polygon |
| RemoveMaterialMode | Removes the specified mode from the current material modes |
| RemoveTextureMode | Removes the specified mode from the current texture modes |
| Rotate | Used with a transformation matrix, rotating it to a given angle |
| Scale | Used with a transformation matrix, scaling it accordingly |
| Specular | Defines how polygons will be affected by specular lighting, currently not used |
| Sphere | Creates a sphere |
| Surface | Defines ambient, diffuse and specular lighting properties in one command |
| Tag | Specifies a tag number to be called for special uses |
| Texture | Defines the texture and mask used in the current material |
| TextureAddressMode | Specifies the texture addressing mode to be used for all following textures |
| TextureMipmapState | Specifies the mipmap state of all following textures |
| TextureMode | Defines the texture mode to be used in the current material |
| Transform | Replaces the current transformation matrix with the specified elements |
| TransformBegin | Defines the beginning of a new transformation matrix |
| TransformEnd | Defines the end of the current transformation matrix |
| Translate | Moves the current transformation matrix |
| Triangle | Creates a triangle based on 3 indexed vertices |
| Vertex | Defines the position of a vertex within the object |
Extension commands
Extra RWX commands are supported by the browser for tweaks. Historically, these were added from version 3.0. To keep scripts compatiable with other software and older versions, these commands make use of a crunchbang "#!" prefix which are otherwise interpeted as comments by non-supported software.
| Command | Function |
|---|---|
| #! OpacityFix on | Start separating the following polygons, to fix transparency issues with neighbor polygons |
| #! OpacityFix off | Stop separating polygons |
| #! Prelight | In conjunction with the Vertex command, defines subtle lighting effects on objects |
| #! Seamless on | Use seamless vertex normals, considering neighbor vertices |
| #! Seamless off | Stop seamless vertex normals |
| #! RandomUVs | Generate random texture coordinates |
| #! TextureAddressMode | Modifies how repeating textures are rendered |
Unsupported commands
The following commands are not supported by the browser. If any of these commands are used in the creation of your object they will be ignored by the rendering engine of the software, additionally some may cause an error message to be displayed.
- AddHint
- Hints
- Include
- IncludeGeometry
- RemoveHint
- TextureDithering
- TextureGammaCorrection
- Trace
- TransformJoint