How do I apply effect on a position?

can i apply effect on a specifique area of an object ? , and if not , is there any other solution to make that happen event using other objects , and blends... ?

probably applying the effect to another sprite on top of the one you want to affect

i thought of that , but it doesn't work , because the target object is a grid tiled backgound , i want to make a ripple effect on a specific part , doing the solution you suggested doesn't work because it's very obvious that there is another object on the grid

You mean something like this? https://dl.dropboxusercontent.com/u/103248101/Construct/index.html

just move your mouse over..

ONLY works in Firefox, Chrome doesn't support the effect

If I understand you correctly, what you can do is to create an empty layer above your grid (lets name it "Ripples"), put the Glass webGL effect on that layer and use a sprite on the "Ripples" layer to push the effect through. The opacity of the sprite will affect how much of the effect will pass through.

See the attached capx.

eli0s thank you soo much that's exactly what i needed , it's a very intelligent idea to do it like that. without even effects. i will try to tweak it in order to get the result i need thank you again.

danuyos thank you man, but didn't want to use that method, i know it works (somehow) but it looks to tally ugly when you set it on a gride you will see the gride lines breakes.

warville , you are welcome! Please keep in mind that you do need to use the Glass webGL effect on a layer! Other than that, yes, it's pretty simple