After some more digging, I wanted to share what I’d found. In this thread, BigDan256 shows how to read Storyboard’s parameters so that you can create your own custom effects:
http://forums.coronalabs.com/topic/23576-custom-storyboard-effect/?hl=%2Bstoryboard+%2Bcustom+%2Btransitions
His var_dump code is fantastic, and when run against the Storyboard module returns a partial list of Storyboard’s effect (from which the others are also derived, I believe). With this info, and BigDan256’s instructions, I created custom slideRight and slideLeft effects for Storyboard. My goal was to be able to use any of the easing options from the easing library (easing.outCubic in my case, which I think looks better than the default easing.outSine that the native ‘slideRight’ and ‘slideLeft’ effects use by default). Here they are:
[lua]storyboard.effectList.slideRightCubic = { sceneAbove = true, concurrent = true, to = { yStart = 0, xStart = -320, xEnd = 0, transition = easing.outCubic, yEnd = 0 }, from = { yStart = 0, xStart = 0, xEnd = 320, transition = easing.outCubic, yEnd = 0 } }
storyboard.effectList.slideLeftCubic = { sceneAbove = true, concurrent = true, to = { yStart = 0, xStart = 320, xEnd = 0, transition = easing.outCubic, yEnd = 0 }, from = { yStart = 0, xStart = 0, xEnd = -320, transition = easing.outCubic, yEnd = 0 } }[/lua]
Be sure to change the transition effect in both the ‘to’ and ‘from’ table so that they match up. While it would still be easier if Corona Labs would just expose the ‘transition’ parameter in Storyboard’s options list by default, this is at least a way that properly allows custom transition effects in Storyboard.