# Using a trigger to detect a range of objects without specifying all objects

**URL:** <https://forum.kirupa.com/t/using-a-trigger-to-detect-a-range-of-objects-without-specifying-all-objects/329598>\
**Category:** flash\
**Created:** [September 20, 2012, 5:46am UTC](https://forum.kirupa.com/t/using-a-trigger-to-detect-a-range-of-objects-without-specifying-all-objects/329598 "2012-09-20T05:46:24Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Zachary\_Hogna](https://avatars.discourse-cdn.com/v4/letter/z/dc4da7/32.png) [@Zachary\_Hogna](https://forum.kirupa.com/u/Zachary_Hogna)\
**Post date:** [September 20, 2012, 5:46am UTC](https://forum.kirupa.com/t/using-a-trigger-to-detect-a-range-of-objects-without-specifying-all-objects/329598/1 "2012-09-20T05:46:24Z")

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Hi guys!

[COLOR=#000000][FONT=verdana]I’m working on a little sidescroller as my first AS3 project.[/FONT][/COLOR]

[COLOR=#000000][FONT=verdana]I’ve been thinking of ways to add shadows that interact with my characters using a colourTransform. [/FONT][/COLOR]

[COLOR=#000000][FONT=verdana]My problem is understanding exactly how classes interact with one another.[/FONT][/COLOR]  
[COLOR=#000000][FONT=verdana]For instance, I have a ‘shadowtrigger’ class instantiated in a ‘Level1’ object with the trigger box object added to the stage. I also have a ‘character’ class instantiated in the ‘Level1’ object and likewise added to the stage. The only way I can think of to get them to interact is to put the hitTest-ing code in the ‘shadowtrigger’ class and have it refer to the character using[/FONT][/COLOR]

[COLOR=#000000][FONT=verdana]ActionScript Code:

([COLOR=#993300]this[/COLOR].parent as [COLOR=#993300]MovieClip[/COLOR]).character

[/FONT][/COLOR]

[COLOR=#000000][FONT=verdana]which as far as I know is not an ideal way to do it. [/FONT][/COLOR]

[COLOR=#000000][FONT=verdana]I want to have an NPC running around (a single basic scripted scene, nothing too crazy) and I want this NPC to be able to trigger and be darkened by this shadowtrigger for as long as it’s within the trigger.[/FONT][/COLOR]

[FONT=verdana, geneva, lucida, lucida grande, arial, helvetica, sans-serif][COLOR=#000000]To save on coding and whatnot, is there any way I can make this trigger detect any moving object and then apply the shadow effects to that object?

I imagine I would have to do something like create a class ‘Character’ then make a bunch of sub-classes then have individual character properties and whatnot, and then have the trigger listen for collisions with class ‘Character’ or something. I’m really not sure!

Thanks heaps![/COLOR][/FONT]