Avoid duplicated $.offset() call

[gagarine]

In the same idea than #48 we can avoid calling offset multiple time.

The Firefox's profiler show me this is where the script use most of the time. For my usage I even create my own offset function than is faster than the jQuery once. I can avoid some test than jQuery need like testing if we are in a iframe or not...

I will be happy to make a pull request but want to know what do you prefer:

• jute avoid unnecessary $.offset() call (their is 4 call by animated object and I can reduce that to one call)
• replace the $.offset() with an alternative function a bit (~20%) faster.

You can see my version performing on http://face-it.ch/fr/mission/congo (it still a work in progress and script are uncompressed at least for the moment).

[janpaepke]

Hi Gagarine,

I saw that John already accepted your pull request. So the update is already in the code...
Thank you for contributing.

regards,
Jan

[gagarine]

Nop it's not the same pull request :).

[gagarine]

As a reference point. On page http://johnpolacek.github.io/superscrollorama/

[janpaepke]

Hi Simon,

sorry for the misunderstanding.

Okay in general I think it's preferable to avoid unnecessary calls instead of replacing the offset function.
But this is a very delicate subject and sometimes a call is needed for the right values.
Please make your changes and send a pull request.

I will then go over your changes and make sure there will be no unexpected behaviour for other users.

thank you and regards,
Jan

[gagarine]

ok this was closed with the pull request #53