TransitionType Enumeration (Microsoft.DirectX.Direct3D)

Defines the transition style between values of a mesh animation.

Definition

Visual Basic Public Enum TransitionType
C# public enum TransitionType
C++ public enum class TransitionType
JScript public enum TransitionType

Members

Member Value Description
EaseInEaseOut 1 Ease-in, ease-out spline transition between values.
Linear 0 Linear transition between values.

Remarks

The calculation for the ramp from ease-in to ease-out is calculated as follows.

Q(t) = 2(x - y)t3 + 3(y - x)t2 + x.

where the ramp is a function Q(t) with the following properties:

  • Q(t) is a cubic spline.
  • Q(t) interpolates between x and y as t ranges from 0 to 1.
  • Q(t) is horizontal when t = 0 and t = 1.

Mathematically, this translates into:

    Q(t) = At3 + Bt2 + Ct + D  (and therefore, Q'(t) = 3At2 + 2Bt + C)

    Q(0) = x     (2a)

    Q(1) = y     (2b)

    Q'(0) = 0    (3a)

    Q'(1) = 0    (3b)

Solving for A, B, C, D:

    D = x  (from 2a)

    C = 0  (from 3a)

    3A + 2B = 0  (from 3b)

    A + B = y - x  (from 2b and D = x)

Therefore:

    A = 2(x - y), B = 3(y - x), C = 0, D = x.

Enumeration Information

Namespace Microsoft.DirectX.Direct3D
Assembly Microsoft.DirectX.Direct3DX (microsoft.directx.direct3dx.dll)
Strong Name Microsoft.DirectX.Direct3DX,  Version=1.0.900.0,  Culture=neutral,  PublicKeyToken=d3231b57b74a1492

See Also