How do I Mask a Layer in Autodesk Sketchbook?

Achieving a masked effect on a layer in Autodesk Sketchbook often involves using selections to define which areas of the layer are visible or edited. One common method, as demonstrated in the provided reference, is to use a selection tool to select the area you want to keep and then delete the unwanted surrounding content on the target layer.

Here’s how you can mask a layer using a selection in Sketchbook:

Understanding the Selection Method for Masking

Unlike some other software that uses dedicated "layer masks" where you paint black or white to hide or reveal parts of a layer non-destructively, Sketchbook uses selections to define editing areas. By making a selection and then deleting the part of the layer outside that selection, you effectively 'mask' the layer's content to fit within the selected shape.

Steps to Mask a Layer Using Selection and Deletion

This technique is particularly useful for confining edits or artwork to a specific shape or area you've defined.

1. Create or Navigate to Your Base Shape/Layer: Have the shape or area you want to mask to defined on one layer, or use a selection based on existing artwork.
2. Make a Selection: Use one of Sketchbook's selection tools (like the Magic Wand, Marquee, Lasso, or Polyline) to select the area you want your target layer's content to appear within.
3. Switch to the Target Layer: In the Layer Editor, select the layer whose content you want to mask or confine to your selection. This is the layer you will be deleting content from.
4. Invert the Selection (if needed): If you selected the area you want to keep, you need to invert the selection to select the area you want to delete. Invert the selection using the Selection menu or interface options. The reference video specifically shows deleting the area outside the shape. As the reference states:

   "And hit the delete. Key. Since I colored in the area outside of my bike shape the area that now I have selected on on this layer. It will delete everything that's in that selection. Now."
   This implies they selected the area outside the desired shape and then deleted it. If you selected the inside, you'd invert first.

5. Delete the Selected Area: With the target layer active and the area you want to remove selected, hit the Delete key on your keyboard. This will clear the pixels in the selected area on that specific layer.

After performing these steps, the content on your target layer will only remain within the boundaries of your original desired shape, effectively creating a masked appearance.

Quick Guide:

Here is a summary of the process:

Step	Action	Purpose
1. Select Area	Use a selection tool to define your mask shape.	Determines the visible part of the layer.
2. Choose Layer	Activate the layer you want to mask.	Specifies which layer is affected.
3. Invert (Opt.)	Invert selection if you selected the inside area.	Ensures you delete the outside area.
4. Delete	Press Delete key.	Removes unwanted content on the active layer.

This method is a fundamental way to control visibility and apply masked effects in Autodesk Sketchbook.