Fade In and Out Using Blend Level: Performance Issues

Sannyasin Brahmanathaswami brahma at hindu.org
Mon Feb 1 23:37:40 EST 2016

I am trying to overcome the limitations we face with Mobile where our transitions are Limited to for example on IOS only flip there is no dissolve or anything like that.

So I am using the blend level of the object or an image in setting this up or down to try and emulate fade in and fadeout effect but we are getting very poor performance. Works OK on desktop.

 it seems also have to have to do with the size of the object for example you can fade in and out. A small object did not see too much of a CPU hit but if you fade in and out an 1200 x 900 pixel Image then on the iPhone it can be very slow even if you have each repeat set to just a few milliseconds… it still takes several secondes to compelte.

 I am using the following handlers if anyone has any ideas about optimizing this I would be very interested. I think probably there's no way to do better and these repeat loops that are forcing the screen to update the entire pixel map are probably always going to perform very badly and I may need to just abandon this effect.

command revealWithBlendLevel, pSpeed,pIterations

   repeat pIterations times

      set the blendlevel of  control gCurrentHiddenControl to pIterations

      subtract 1 from pIterations

      wait pSpeed milliseconds

   end repeat

end revealWithBlendLevel

on fadeInObject pLevel

      put 1 into tIncr

   repeat pLevel times

      set the blendlevel of image 1 to tIncr

      add 1 to tIncr

      wait 10 milliseconds

   end repeat

end fadeInObject

command fadeOutCurrentControl pSpeed

   put (the blendlevel of control gCurrentShowingControl) +1 into tLevel

   set the blendlevel of control gCurrentShowingControl to tLevel

   if tLevel < 100 then

      send fadeOutCurrentControl to this stack in pSpeed ticks



   end if

end fadeOutCurrentControl


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