A rotating scroll through

After the rotation, we want to scroll through the cornea while it is rotating around it’s z-axis. Scrolling through is implemented by adding the following lines:

From frame 90 to frame 450:
- change bounding box max z to 0

Note that we decrease the bounding box max z (and not increase min z) because we turned the cornea by 180 degrees.

For the rotation, we could just add another line right after:

- rotate by 360 degrees around (0, 0, 1)

However, this would apply the rotation after the 10-degree orientation adjustments in the beginning, i.e. rotate around the view’s and not the cornea’s z-axis. This looks a bit strange in combination with the scroll-through. Instead, the rotation is added at the beginning of the script:

From frame 90 to frame 450:
- rotate by 360 degrees around (0, 0, 1)

At frame 0:
- rotate by 10 degrees vertically
- rotate by 10 degrees horizontally
- change front clipping to -120
- change bounding box max z to 500

From frame 0 to frame 90:
- rotate by 180 degrees vertically
- zoom by a factor of zoom


From frame 90 to frame 450:
- change bounding box max z to 0

script
function zoom(t) {
	return 0.6 - 0.3 * abs (sin (2 * PI * t / 180));
}

This is the entire script for the cornea animation. The result can be found here.