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# kTween3dInitialCondition

An atom that specifies an initial transform for a 3D tween atom.

## Overview

Specifies an initial transform for a 3D tween atom whose tween type is one of the following: `kTweenType3dCameraData`, `kTweenType3dMatrix`, `kTweenType3dQuaternion`, `kTweenType3dRotate`, `kTweenType3dRotateAboutAxis`, `kTweenType3dRotateAboutAxis`, `kTweenType3dRotateAboutPoint`, `kTweenType3dRotateAboutVector`, `kTweenType3dScale`, or `kTweenType3dTranslate`.

Its parent atom is a `kTweenEntry` atom.

A `kTweenEntry` atom can contain only one `kTween3dInitialCondition` atom. The ID of this atom is always `1`. The index of this atom is always `1`.

This atom is a leaf atom. The data type of its data is one of the values listed in the following table.

|Tween type                     |Data type                         |
|-------------------------------|----------------------------------|
|`kTweenType3dCameraData`       |`TQ3CameraData`                   |
|`kTweenType3dMatrix`           |`TQ3Matrix4x4`                    |
|`kTweenType3dQuaternion`       |`TQ3Quaternion`                   |
|`kTweenType3dRotate`           |`TQ3RotateTransformData`          |
|`kTweenType3dRotateAboutAxis`  |`TQ3RotateAboutAxisTransformData` |
|`kTweenType3dRotateAboutPoint` |`TQ3RotateAboutPointTransformData`|
|`kTweenType3dRotateAboutVector`|`TQ3PlaneEquation`                |
|`kTweenType3dScale`            |`TQ3Vector3D`                     |
|`kTweenType3dTranslate`        |`TQ3Vector3D`                     |

This atom is optional. For each tween type, the default value is the data structure that specifies an identity transform, that is, a transform that does not alter the 3D data.

---

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