Image Layers

To create a new image layer you can follow these simple steps :

• If you want to create the layer from any picture file, right click on the layers list and choose Create new layer from file.. ;
• if you want to create a layer from the current selection just choose from main menu Edit > copy and then choose Edit > Paste as new layer.
• You can also create a blank layer: right click the layers list and choose Create new blank layer.
• Remember also that you can create a layer from the current Object just by promoting it to a layer (Object > Promote to layer).
• A new layer is created and the layer window is opened .
• Now you can control all about the newly created layer: position, name, opacity (in %) etc..from the Layers window
  

Commands of Layer Window:

Layers List: it lists all the existing image Layers: the layers with a check are those which are visible.

The background is a special layer and thus is always visible.

The lower is the layer in the list the more it is displayed in front of other layers.

Z-Order Arrows:

Use the arrows to bring a layer on top of another or back.

Merge Button:

This command merges the layer with the background. After the merge, the layer is not deleted but just made invisible. If you need to you can delete the layer yourself.

Delete Button:

Command to delete a layer: warning this operation cannot be undone, so be careful before deleting a layer.

Layer Display:

It shows the 4 channels of which the layer is made. The 3 color channels produce the picture on the left the alpha channel is the gray picture on the right.

There is also the Blend Mode, which is the way the layer is combined with the background and the underlaying layers. By Default the blend mode is set to Normal.

You can also control:

• Percent of blending (opacity)
• Layer Position (X, Y)
• Layer Width and Height
  

The Alpha Channel

An image layer is made of 4 channels: 3 RGB channels represent the color information, and the alpha channel is an extra information which represents the opacity of the layer: the more is the value of alpha channel the more the layer will be visible. Each pixel of the layer can have a different alpha value, pixels which have 0 will not be visible, pixels which will have 127 will be just half-visible and pixels which have maximum value 255 will be completely visible.

You can edit the alpha channel separately using the alpha channel editor.

To cut away parts of the alpha channels you can use the Edit > Cut Command together with a selection.

You can also modify the transparence of alpha channel using the "Erase/Restore layer tool".

Also if in the Layer Window the Edit Alpha Channel option is checked you will be able to edit the alpha channel with most of the editing tools. If the option is not checked the alpha channel will not be affected during editing.

These are also many operations you can do with Image Layers like:

• Rename a Layer
• Duplicate a Layer: which creates an exact copy of the current layer
• Merge with Background: which merges the current layer with the background into just one picture.
• Position: this lets you align the layer position to the center, the left, the top, the right and the bottom
• Copy to Object: this creates an object from current layer: it's useful if you want to paste the layer into another project, then first you create an intermediate object.
• Group Layers: when you click this menu item the Group Layers window will show:

From this window you can:

• Move to the list on the right all layers that you want to group
• Choose the operation you want to apply to the group
• Press the Apply button to apply the selected operation.

- "Flatten Group" operation has the effect of joining all the layers of the group into one big layer. The old layers will not be deleted but just set to invisible in case you want to restore them later.

- You can also apply group alignment operations to set the position of all layers in the group