Supported Scene Elements and Attributes for COLLADA

Polygon Meshes

Yes

Polygons

Yes

When exporting, Softimage uses the <polylist> element instead of the <polygons> element. Since Softimage does not export polygon holes, the <polylist> element is used for its more compact representation. However, the <polygons> element is supported on import.

Polygon Vertex Clusters

Yes, on export.

No, on import.

Splines

No

Nulls

Yes

Vertex Color

Yes

Also referred to as color at vertices (CAV) properties.

Texture Tangents

Yes

Tangents and binormals are stored in color at vertices (CAV) properties. Crosswalk identifies whether or not a CAV property contains tangent or binormal data as follows: Crosswalk looks for the TangentOp2 operator.

• IIn Softimage 6.5 and earlier, if the operator is present, tangent data is assumed and exported (binormals were not directly supported). When exporting, binormals should be recomputed by the cross product of the normals and the texture tangents.

• IIn Softimage 7.0 and later, if the operator is present, then Crosswalk reads the Operator Type flag which indicates whether tangents or binormals should be exported.

If Crosswalk does not find a TangentOp2 operator, then it looks for the sub-string tangent or binormal in the CAV property's name.

If you renamed the property and did not retain tangent or binormal as part of the name, the property will be exported as vertex colors only.

In COLLADA, tangents and binormals map to the "TEXTANGENT" and "TEXBINORMAL" semantics. Example:

<polylist count="6" material="Scene_Material">

...

<input semantic="TEXTANGENT" source="#geometries_0-Tangents" offset="2"/>

<input semantic="TEXBINORMAL" source="#geometries_0-Binormals" offset="3"/>

</polylist>

For more information, see Working with Tangent and Binormal Maps [Texturing].

Ambient

Yes

Prior to Crosswalk 3.1, ambient lights were imported at the scene origin and converted to point lights.

Point

Yes

Light Common Shading

Yes

When importing a light, its intensity is set to 1.0 if no XSI Extra is present.

Perspective Lookat

Yes

Orthogonal

No

Orthographic cameras are not exported and they are converted to a perspective camera on import.

SRT Node Transforms

Yes

Instances (model)

Yes

Envelopes

Yes

Including bind pose matrices and envelope weights.

In addition, Crosswalk adds type="JOINT" on all nodes (envelope deformers) that are a part of a skeleton's hierarchy. This is done to support applications that rely on the type="JOINT" description to import envelopes/skins properly. This applies only to the export of envelope deformers from Crosswalk.

Bones

No

Converted to nulls.

Fcurves (constant)

Yes

Fcurves (spline)

Yes

Fcurves (per key interpolation)

No

Constraints

No

Plotted on export using Animation Resampling options.

Rigid Body Dynamics

No

Common Shading

Yes

The common profile is fully supported. The exporter analyzes the material render tree and guesstimates the best approximation to convert from a full-fledged shader node network to the common profile. The ProgID of the first shader attached to the surface port of the material is the one that drives the common profile description. For example, if the first shader attached to the material's surface port has a ProgID that is "softimage.phong.1", then the exporter will generate a <phong> element within the effect description. Textures attached to the emission, diffuse, specular, and ambient ports are also exported and imported correctly.

Support for alpha-driven transparency with a texture is handled as follows:

• When exporting "Use Alpha" with a texture the "Scale" is not taken into account.

• When exporting "Use Alpha" with a color, the "Scale" is baked into the color.

• When importing in the A_ONE mode with a texture, the COLLADA "Transparency" is ignored and the "Scale" is set to 1.0.

• When importing in the A_ONE mode with a color, the COLLADA "Transparency" is baked into the color and the "Scale" is set to 1.0.

Cg Profile Effects

Yes

CG profile is supported in two flavors: The first flavor uses the NV_import extra which references an external CGFX file. This is used when the CGFX shader node attached to the material is using an external reference to a CGFX file.

The output looks like this:

<effect id="check3d_fx">

<extra type="import">

<technique profile="NV_import">

<import profile="cgfx" url="file://\lobby\dev\CGFX\check3d.cgfx" />

</technique>

</extra>

</effect>

The second flavor uses the full COLLADA FX specification for the CG profile. The effect description needs to be set within the CGFX node in order to work.

Custom Psets

Yes

Foreign Extras

Yes

The foreign extra element does not use the Softimage technique profile. These extras are imported and persisted as opaque user data blobs in the Softimage scene. They are restored on export.

Model Files

No

Shaders

Yes

COLLADA Files

No

Softimage only supports external references to images and CGFX files. References to COLLADA files are not supported — resolve them within the same document instead.

Update

No