frame-sequence

A simple parser for frame sequences strings.

This will parse a [str] describing a sequence of frames into a [Vec]<isize> containing individual frame numbers.

Mainly intended/useful for rendering/animation/VFX applications.

Example Frame Sequence Strings

Individual frames:

1,2,3,5,8,13 ⟶ [1, 2, 3, 5, 8, 13]

A sequence:

10-15 ⟶ [10, 11, 12, 13, 14, 15]

With step size:

10-20@2 ⟶ [10, 12, 14, 16, 18, 20]

Step size must be always positive.

To get a sequence backwards specify the range in reverse:

42-33@3 ⟶ [42, 39, 36, 33]

With binary splitting:

10-20@b ⟶ [10, 20, 15, 12, 17, 11, 13, 16, 18, 14, 19]

The last frame of a sequence will be omitted if the specified step size does not touch it:

80-70@4 ⟶ [80, 76, 72]

Nuke-Style Step Size Token

Using x instead of @ as the step size token separator also works.