layers

Layers feature handles multiple bitmaps that overlay the root layer. The user must be able to re-order, show/hide, lock, and add/remove effects to/from a layer item. Layers can be grouped together under a label.

Effects are contractors apps which can be applied non-destructively to a layer. Effects are a special grouping layer that can be parented to a layer. An effect holds a list of effects that are being applied to a layer. Effects can be toggled on/off and added/removed. Layers can be parented to a effects layer.

Mask are a special layer which can be applied to one or multiple layers. Mask can be toggled on/off and added/removed.

Layers should be indented based on there hierarchical position. There should be no more levels then Grandfather ->Father->Son.

Eg
+ Layer_group
++ Mask
+++ Layer1
++ Layer2

Layers should also have blending: opacity/fill sliders, with sublayers that allow the user to edit each channel r g b a.