Shade and lighten

Shade (S) and Lighten (O) share a button. Paint over pixels to make them one step darker or lighter. Right-click does the opposite.

The Mode in their options says what “one step” is:

• Same ramp (the default): the next color of the same ramp in the palette, from its darkest to its lightest. Shadows stay in the material’s colors.
• Whole palette: the next palette color by lightness, from any ramp.
• Free: the color itself made darker or lighter, outside the palette, by 1 to 3 steps (Strength). Hue shift turns the hue as it goes, highlights toward yellow and shadows toward blue-violet, the way pixel artists color.

Each stroke steps a pixel once, however long you paint over it: paint again for another step.

The light

The light is a beta: it may still change, and feedback on it is welcome in the discussions.

Shading holds together when every shape takes its light from the same side. The Light section of the right panel sets that side for the board: click +, then drag the lamp around the little sphere. Around it is the angle, from any direction; nearer the sphere is a light from high above, farther a low, grazing one. The sphere shades as the light falls on it, and its shadow stretches on the ground. The angle and height fields below set them to the degree, and with the stage focused, the arrow keys turn the light (Shift by 15°) and raise or lower it.

Direction on the canvas draws faint parallel lines running from the light over the board, and a sun at its edge where the light comes from: drag the sun around the board to turn the light, and the stage follows. They’re a guide, like the grid: never painted, never exported.

A layer’s drop shadow can follow the light (a box under its X and Y, in the Effects section): it then falls away from the light, longer the lower the light is, and moves when you move the lamp, on every layer that follows it. Setting X or Y by hand stops it following. If the layer has no such shadow yet, Add a shadow that follows it, in the Light section, adds one.

The light is saved with the board, each board its own, and − takes it away.