Detect colour beneath an img object

Thomas McGrath III 3mcgrath at comcast.net
Sat Jun 21 22:55:30 EDT 2008


Barry,

This is actually more complicated than a simple under message (which  
does not exist). Have you looked into collision detection? Have you  
checked out the new and improved Animation Engine. imageCollide comes  
to mind. You might need to do something with points etc. instead of a  
color in an image. Do you have a sample stack that shows what you need  
to do?


Tom McGrath


On Jun 21, 2008, at 3:21 PM, Barry Barber wrote:

> Thank you Eric, but nobody is using the mouse in this part of the  
> game.
> I
> think I need a script in the card that passes a message to each of
> several objects to determine which is above the given colour.
> Oh! I
> knew I should'nt have asked this silly question but I can't find any
> property/attribute like "under", [underneath], [below], [beneath] in  
> the docs!
> As usual I have a beautiful UI that I'm not capable of scripting. :-(
> Gratefully
> Barry
> -----------------------------
> Original post:
>> Hi all
>> This question will probably (I hope) be easier for some of you to  
>> answer than for me formulate!
>> I am trying to detect when the colour changes below the loc of an  
>> image (png) object lying
>> above another of the same type. The catch is that the top img would  
>> "see" the underlying one
>> through a hole in another png which is on an intermediate level  
>> between the two of them!
>
>> To put it another way: there are three png images directly  
>> superimposed, the one on the middle
>> layer has a 'hole' in it and I need the top layer to detect when it  
>> is over the hole (i.e., detect the
>> change in colour beneath it's loc).
>> Here's hoping!
>> Barry Barber




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