I have hundreds of layers on an image. I would like to add a layer especially dedicated on transparency - so that I can add transparency to the areas of the image, without modifying the other layers. How could I do that without flattening the other layers ?
Here is the beautifully drawn example :
I would like to add one layer on the top to determine what areas are transparent (the white part should be transparent)
I cannot merge the other layers, and adding the same layer mask to all the layers is not possible.