Comet control script videos (updated)

As demonstrated in the screencast below, the user can write scripts to:
1) control the coma size,
2) return to the default coma size,
3) increase/ decrease the plasma tail length,
4) increase/ decrease the dust tail length.

(View in full screen)

Note:
- The coma, dust tail and plasma tail size was enlarged so that it's easier to see in the video. The actual code makes the comet a lot smaller. For example, the currently only possibly visible-tails comet, P/2005 K3 (McNaught), which is less than 1.0 AU from the Sun and therefore the solar heat is enough to melt the ice for us to see the dust tail. (see below video for actual representation)
- At other times, the dust tail and plasma were more distinct from each other, but from this angle they overlap.

Video of actual size in Stellarium
How you would see it when the sizes are not artificially enlarged for debugging purposes:

(View in full screen)

Here are the public slots (a kind of Qt-unique functions) that are available from the CometMgr class:
void setDefaultComaSize()
Revert current coma size to the default size.
void plasmaTailLengthMultBy(float factor)
Multiply current plasma tail length by "factor". Not allowed to be negative number.
void dustTailLengthMultBy(float factor)
Multiply current dust tail length by "factor". Not allowed to be negative number.
void comaBurstTo(float new)
Set the coma size to "new". Note, the more negative, the larger the coma will be. Limited to -50 < new < 50
float getDefaultComaSize()
Get default coma size for when you want to adjust the coma more realistically according to how much you change the tail lengths

Future possibilities:
Illustration of nucleus split and collision with Sun.
But first, I would have to improve the tail rendering to be more physically realistic and clear bugs.