Compute event.lastFrameTime
Posted on Fri, 2009-12-04 16:44
This piece of code will compute the last-frame-time (very useful when doing time-based animation) and make it available to all enterFrame event handlers that follow. You'll want to place/require() this code very early (if not first) in your program:
1 2 3 4 5 6 7 8 9 | local function onEnterFrame_computeLastFrameTime() local prev_time = nil return function( event ) prev_time = prev_time or event.time event.lastFrameTime = (event.time - prev_time) / 1000 -- '/ 1000' converts from msecs to secs prev_time = event.time end end Runtime:addEventListener( "enterFrame", onEnterFrame_computeLastFrameTime() ) |
David
I like how you keep prev_time local by returning a function.
That's a useful pattern!
Thanks, Arjan