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Boolean & liquid shapes

Two ways to combine vector shapes: the destructive Pathfinder buttons on the toolbar, and the live boolean group you get from the Object menu.

Celas Studio has two boolean systems and they are deliberately different. The Pathfinder buttons on the toolbar consume the shapes you selected and hand back one new shape. The boolean group wraps the same shapes in a group and computes the result while you keep editing the parts. Both need at least two selected Shape layers.

Pathfinder: one new shape

The Pathfinder group sits on the toolbar as five buttons: Add (Union), Subtract, Intersect, Xor and Divide. When the window is narrow the group collapses to the button you used last and fans out when you hover it.

  • Add (Union) fuses the selection into one outline.
  • Subtract cuts the shapes above out of the bottom one.
  • Intersect keeps only what all of them cover.
  • Xor keeps everything except the overlap, so the overlap becomes a hole.
  • Divide cuts the selection along every edge and keeps each resulting piece.

The operands are removed and replaced with the result, which is a single Shape layer: a compound one when the outcome has holes or separate islands. It is a normal editable path, so you can carry on with the Node tool afterwards.

Divide and Separate

Divide and Xor have a second job. Run either on a single compound shape and Celas Studio releases every contour into its own Shape layer, each named Path. That is the way to break an erased or imported outline back into separate pieces. The released pieces start clean: their animation is not carried over.

Releasing contours resets the animation on the pieces. Do it before you key a shape, not after.

The boolean group: still live

Select two or more shapes and choose Object ▸ Boolean ▸ Union (Liquid Shape), Subtract, Intersect or XOR. The same four sit on the Move tool options bar, behind the word Boolean, and are greyed out until there is something to do with them. Celas Studio inserts a group at the position of the front-most selected shape, moves the shapes into it, and sets the group's boolean mode.

Nothing is destroyed. Open the group and every original shape is still there, still animatable. Move one and the result follows. The group is named after its mode, and you can change the mode at any time: with the group selected, those four buttons show which one it is on and a click switches it in place, without unwrapping and rebuilding. Properties carries the same control, in the Boolean / Liquid Shape section, and that is where you set the mode back to None for an ordinary group of separate shapes again.

A boolean group in the Layers panel with its two source shapes still listed as children, the four mode buttons on the options bar with the current one active, and the Blend Radius box beside them.

Liquid union

A boolean group also has a Blend Radius, from 0 to 1000 px. At 0 the union is a hard one: outlines simply merge. Above 0 the shapes reach for each other and melt together with a smooth neck, the way two drops of water join. Blend Radius is keyframeable, so a splash can pull apart over time. It sits beside the four mode buttons on the options bar whenever a boolean group is selected, and in Properties, reading the same number in both places.

Which one to use

Reach for Pathfinder when the combination is a decision you have made (a silhouette you will now edit as one path) and when you need Divide, which the group has no equivalent for. Reach for the boolean group when the parts must stay editable or animated, when you want to try the mode out, or when you want the liquid blend.

Two practical limits are worth knowing. Corner radius does not apply to the extra contours of a compound shape, so radii on a Pathfinder result with holes will not show. And boolean operations have no keyboard shortcuts in Early Access. They are toolbar and menu only.

The result is cleaned before it is handed back: rings thinner than a twentieth of a pixel are dropped, and the point-reduction pass runs at a tolerance fine enough that it cannot round a real corner away. That is what stops a Union of Divide pieces from reopening along the seams it just closed.