Create image scrolling area

I need to create an area (a simple transparent square of 150x150 pixels) inside my game screen where I can insert images that the player can scroll. Anything that exceeds the edges of the area must be cut off.

To make you understand better what I'm talking about, I leave you a simple example of a CodePen (it's not an example of a real game, but the scrolling and cutting effect is what I would like to obtain): https://codepen.io/shadeed/pen/jOMrxYO

Initially I thought of inserting a check inside the images, where I checked if the image was > or < of the upper and lower y points of the area. If the image was outside the area I set an opacity equal to 0 (so no longer visible and hidden).

But this method created two problems:

- The image didn't get a cut effect (i.e. it wasn't shown halfway when it was in a position halfway between an edge of the area)

- I use the same object also for instances that are outside the area. If I make a control on the same object I risk that any instances present in the scene would be hidden if not inside the area

Can anyone give me some advice on how to properly set up a scrolling area like this?

Yeah, this is one of hurdles when doing gui in C3 as there's no simple way to do it.

The standard method is to use blend modes with destination out giving a mask effect.

You move the objects over the area and the mask cuts off the parts outside of it.

This is about as simple as it can get. dropbox.com/s/mey5ydzh0ksiw03/blendmask.c3p

Note that the layer its on is set to "force own texture"

Thank you so much for the example!

Is there a specific reason why you recommended that I enable the "force own texture" option for this effect?

you can fake that effect, by having the items in grid pattern like in the website example, covered by a boundary "sprite object" and make the items scrollable by pinning them to a tile background object that u drag left and right. there was a tutorial on this in the old "tutorial area" of website. not sure if still around. was called something drag scrolling object "mobile"

Force own texture on a layer will prevent blend modes from affecting anything on other layers below it.

Thank you all for your responses and advice.

I was able to solve it by following newt's advice.^^