Set viewport/layout HEIGHT scale?

I'd like the effect on Mickey Mouse's Castle Of Illusion where you turn the gravity upside down and it squashes the game viewport to a slither then stretches back out and the viewport is upside down. How do you adjust the "screen size" or the camera area's HEIGHT at runtime? I can do layout scale but I need to squash and stretch the height, preferably into negative values so as to create a vertical flip when it reaches -100% scale.

Sounds like a job for shaders. My scale effect is based on the bottom left at the moment, but could be modified to center vertically.

But if you aim for a mobile platform then shaders aren't reliable.

Can you share a video of the effect in action in Castle of illusion?

Sorry for the delay, it took me a while to find the video (I was thinking it was the sms version!)

you can see it goes from 100% to 0% until finally -100% with the negative values being the image vertically upside down. Would this be possible to implement as an effects shader?

EDITED: correct link!

From the description that sounds quite doable, but the video link is not the right one

Whoooooops! I went to some effort to get the right timecode too! Here it is <img src="{SMILIES_PATH}/icon_e_biggrin.gif" alt=":D" title="Very Happy">