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Light layers

Paint soft-edged light and shadow shapes over flat-coloured artwork, and control every kind of light for the whole project from the Light panel.

A Light layer holds one or more closed paths whose inside is lit or shaded and whose edge fades out softly. You use it the way a lighting pass is used on flat-coloured animation: draw a shadow shape, a rim light or a patch of ambient occlusion over the artwork, and the layer paints it in the light's colour with a fitting blend mode.

A Light layer is edited like a Shape layer. The Node tool, vertex keyframes, welds and bone binding all work on its paths. Only what it draws is different: the fill and stroke are not drawn, the soft light is.

A flat-coloured character with a soft blue shadow shape and a thin warm rim light painted over it by two Light layers.

Making a Light layer

  • Click the Light button in the row of add-layer buttons in the Layers panel.
  • To light something you already drew, select a Shape layer and choose Convert to Light Layer from the Layers panel right-click menu or the canvas right-click menu. The shape's paths become the light's paths.

A new light starts empty. Open the Light panel and use Add Circle or Add Square to give it a first path, then shape that path with the Node tool.

To keep a light inside the artwork it belongs to, make it a child of that layer and turn on Clipping Mask on the parent. The light then never spills outside the parent's pixels. Clipping Alpha on a light layer, or on a group holding it, keeps the light off the transparent parts below it.

The soft edge

Every vertex of a light path has a second point, the feather point, which marks where the soft edge ends. The distance between a vertex and its feather point is how far the light fades out there. When they sit on top of each other the edge is hard.

Feather points are free: in the Node tool you can drag each one on its own and pull its own bezier handles, so the fade can be long on one side and short on another. With Link Feather to Vertex on, a feather point follows its vertex when you move it. The Node tool bar has three switches for this: Feather Points, Feather Handles and Link Feather to Vertex.

For an even soft edge without placing points by hand, set Feather in the Light panel: it sets how far every vertex of the chosen path fades out.

The Node tool on a light path with the feather points and their handles drawn outside the path's outline.

Paths, kinds and combine modes

A light layer can hold several paths. The layer itself has no kind and no blend mode of its own. Every closed path has its own settings:

  • Kind: what the path represents. Shadow, Sunny Side, Ambient Occlusion, Secondary, Ambient, Custom, Translucent, Subsurface Skin, Subsurface Other, Specular and Rim Light. Each kind has its own colour and a fitting blend mode, so a Shadow darkens and a Rim Light brightens without you choosing a blend mode. A path can also use the Layer's kind.
  • Mode: how the path combines with the other paths of the same kind above it in the list. Add, Subtract, Intersect or XOR. The combining is live and nothing is cut: change the mode back and the path is whole again.
  • Opacity: the path's own strength, applied before it combines with the others.
  • Feather: how far the soft edge reaches.
  • The eye in the path list hides or shows one path.

The same four combine modes are on the pathfinder buttons: select paths of a light layer with the Node tool and click Union, Subtract, Intersect or XOR. On a light layer these set each path's Mode instead of cutting the shapes apart.

A light layer drawn over something it is not a child of still blends with the layers below it, on the canvas as well as in exports.

The Light panel

The Light panel has two tabs.

Layer

The Layer tab works on the selected light layer. Select a light layer first; otherwise the panel asks you to. The left column lists the layer's paths, the right column holds the settings of the chosen path.

  • Click a path in the list to choose it. Its vertices are selected in the Node tool at the same time.
  • Double-click a path to rename it. Clear the name to go back to Path 1, Path 2 and so on.
  • Drag a path up or down the list to reorder it. Paths combine in list order.
  • Click the eye on a row to hide the path.
  • Under the list, Add Circle and Add Square add a new path in the middle of the canvas, and Delete Path removes the chosen one.
  • On the right, set the path's Kind, Mode, Opacity and Feather.
The Light panel on its Layer tab: three paths in the list on the left, and Kind, Mode, Opacity and Feather for the chosen path on the right.

Global

The Global tab has one row for each kind of light: an eye, a colour swatch, the kind's name and a strength slider. These settings are for the whole document. Change the colour of Shadow once and every shadow in the project follows. The eye hides that kind of light on every light layer at once.

A light layer follows the global row of its kind by default. If a layer needs its own colour, it can replace the global one with a colour of its own.

The settings in the Light panel are not saved as part of any one layer's look. Changes to them show on the canvas straight away, and each change is a single undo step.

Working with Light layers

  • With the Move tool, double-click a light layer to go into it, click a path to pick it and drag to move it whole. See Move tool.
  • With the Node tool, Auto Select can be set to Light so that a click picks lights only, and an edge click adds a node on every path of the light. See Node tool.
  • In the Layers panel a light layer shows a warm light icon instead of a thumbnail, and the type filter can show only lights. See Layers panel.
  • Light layers can be keyed and bound to bones like any other Shape layer.

See Layer types for how a Light layer compares with the other kinds of layer.