T3D File Format Specification

There are four types of objects that a T3D file can contain: polygons, brushes (groups of polygons), actors, and maps (groups of brushes and actors). Polygons and actors are never included on their own; they are only used to make up brushes and maps, respectively.

Polygons

Begin Polygon [Item=<ItemName>] [Texture=<Texture>] [Flags=<Flags>] [Link=<Link>]

      [Origin     <BaseVector>]

      [Normal     <NormalVector>]

      [Pan        [U=<UPan>]          [V=<VPan>]]

      [TextureU   <TextureUVector>]

      [TextureV   <TextureVVector>]

      Vertex      <VertexVector>

      Vertex      <VertexVector>

      ...

End Polygon

<ItemName>

Not Used. The name of the polygon. Only used when selecting polygons within the editor. Will be saved/reloaded upon export regarding the selected polygons of the brush

<Texture>

The texture of the polygon. Must be specified in Package.Texture format.

<Flags>

The flags of the polygon. The flags and their meanings can be found in the polygon flags section at the end of this document. It ignores the NoImport flag upon importing.

<Link>

This is the index of the surface for this particular polygon. In general, there is one surface per polygon. The default for this is the number of the polygon, allowing each polygon to have it's own surface. In some cases, such as when "Merge Coplanars" is used on a brush, or a brush is validated, any coplanar polygons will have their iLinks set to point to the same surface, indicating that all of the polygons lie on the same plane.

<Origin>

The origin of the polygon. If not specified, it defaults to the first Vertex listed.

<Normal>

The normal of the polygon. Upon import, UT ignores and recalculates the normal itself. The normal is the vector heading towards you when you look at the polygon such that its points are listed in a counterclockwise fashion. In other words, the normal is the cross product of a line segment with it's subsequent line segment. This property (in the t3d file) is only useful upon export when one needs the normals without calculations.

<UPan> & <VPan>

The U (X) and V (Y) offsets. These define the offset with which the texture is placed into the polygon, so that the texture does not need to be flush with the polygon. Setting UPan to five shifts the texture five units to the left, obscuring the leftmost five units of the texture.

<TextureUVector> & <TextureVVector>

The U (X) and V (Y) directions on this polygon. Changing these causes the orientation as well as the scaling of the texture to vary. The TextureU and TextureV can be thought of as the vectors defining the coordinate system. Their direction defines the direction that the texture is applied to the polygon. The TextureU vector should be pointing to the right side of the polygon's texture, while TextureV should be pointing to the bottom of the polygon's texture. For normal scaling, these vectors should be unit vectors in their respective directions. Doubling either of the magnitudes of these vectors causes a doubling in the size of the texture in that respective direction. By default, TextureU is the normal parallel to the first line segment listed, while TextureV is perpendicular to that and the normal, a normal pointing downwards. Since they are both normals, they will cause the texture to be applied with a 1:1 scaling by default.

<VectorVector>

This is a point on the polygon. These points should be listed in counterclockwise order around the polygon, so that the normal will be facing into the viewer.

Brushes (PolyLists)

Begin PolyList

      Begin Polygon

            ...

      End Polygon

      Begin Polygon

            ...

      End Polygon

      ...

End PolyList

Actors

Begin Actor Class=<ClassName> Name=<Name>

      <PropertyName>=<PropertyValue>

      <PropertyName>=<PropertyValue>

      ...

End Actor

<ClassName>

The classname of this actor, in the format PackageName.ClassName

<Name>

The unique identifying name of this actor

<PropertyName>

Some property of the actor

<PropertyValue>

The value of the associated property of the actor, as it differs from the actor's defaultproperties

One important point to mention is that brushes are also actors. So brushes can follow the same form, to a degree. They follow the standard "Begin Actor" format, but their contents change to allow for polygon list definitions, which give the information needed to reconstruct the brush. This is the form used specifically with map files.

Begin Actor Class=Brush Name=<Name>

      Begin Brush Name=<Name>

            Begin PolyList

                  ...

            End PolyList

      End Brush

End Actor

<Name>

There is only one name for the brush, and it should be used in both places listed above.

Maps

Begin Map

      Begin Actor Class=... Name=...

            ...

      End Actor

	  Begin Actor Class=... Name=...

      	  ...

	  End Actor

	  ...

End Map

Polygon Flags

In-game flags:

PF_Invisible, 0x00000001

Polygon is invisible.

PF_Masked, 0x00000002

Polygon should be drawn masked.

PF_Translucent, 0x00000004

Polygon is transparent.

PF_NotSolid, 0x00000008

Polygon is not solid doesn't block.

PF_Environment, 0x00000010

Polygon should be drawn environment mapped.

PF_ForceViewZone, 0x00000010

Force current iViewZone in OccludeBSP (reuse Environment flag)

PF_Semisolid, 0x00000020

Polygon is semi-solid, collision solid CSG nonsolid.

PF_Modulated, 0x00000040

Modulation transparency.

PF_FakeBackdrop, 0x00000080

Polygon looks exactly like backdrop.

PF_TwoSided, 0x00000100

Polygon is visible from both sides.

PF_AutoUPan, 0x00000200

Automatically pans in U direction.

PF_AutoVPan, 0x00000400

Automatically pans in V direction.

PF_NoSmooth, 0x00000800

Don't smooth textures.

PF_BigWavy, 0x00001000

Polygon has a big wavy pattern in it.

PF_SpecialPolygon, 0x00001000

Game-specific Polygon-level render control (reuse BigWavy flag)

PF_SmallWavy, 0x00002000

Small wavy pattern (for water/enviro reflection).

PF_Flat, 0x00004000

Flat surface.

PF_LowShadowDetail, 0x00008000

Low detail shadows.

PF_NoMerge, 0x00010000

Don't merge Polygon's nodes before lighting when rendering.

PF_CloudWavy, 0x00020000

Polygon appears wavy like clouds.

PF_DirtyShadows, 0x00040000

Dirty shadows.

PF_BrightCorners, 0x00080000

Brighten convex corners.

PF_SpecialLit, 0x00100000

Only speciallit lights apply to this Polygon.

PF_Gouraud, 0x00200000

Gouraud shaded.

PF_NoBoundRejection, 0x00200000

Disable bounds rejection in OccludeBSP (reuse Gouraud flag)

PF_Unlit, 0x00400000

Unlit.

PF_HighShadowDetail, 0x00800000

High detail shadows.

PF_Portal, 0x04000000

Portal between iZones.

PF_Mirrored, 0x08000000

Reflective surface.

Editor flags:

PF_Memorized, 0x01000000

Editor: Polygon is remembered.

PF_Selected, 0x02000000

Editor: Polygon is selected.

PF_Highlighted, 0x10000000

Editor: Polygon is highlighted.

PF_FlatShaded, 0x40000000

FPolygon has been split by SplitPolygonWithPlane.

Internal flags:

PF_EdProcessed, 0x40000000

FPolygon was already processed in editorBuildFPolygons.

PF_EdCut, 0x80000000

FPolygon has been split by SplitPolygonWithPlane.

PF_RenderFog, 0x40000000

Render with fogmapping.

PF_Occlude, 0x80000000

Occludes even if PF_NoOcclude.

PF_RenderHint, 0x01000000

Rendering optimization hint.

Combinations of flags:

PF_NoOcclude, PF_Masked | PF_Translucent | PF_Invisible | PF_Modulated

PF_NoEdit, PF_Memorized | PF_Selected | PF_EdProcessed | PF_NoMerge | PF_EdCut

PF_NoImport, PF_NoEdit | PF_NoMerge | PF_Memorized | PF_Selected | PF_EdProcessed | PF_EdCut

PF_AddLast, PF_Semisolid | PF_NotSolid

PF_NoAddToBSP, PF_EdCut | PF_EdProcessed | PF_Selected | PF_Memorized

PF_NoShadows, PF_Unlit | PF_Invisible | PF_Environment | PF_FakeBackdrop

PF_Transient, PF_Highlighted

Last updated: Wednesday, October 25, 2000 7:04:34 AM