Combining shapes

1What booleans do, and why people love them

In tools that have them, boolean shape modes let one shape add to, subtract from, or clip another automatically, so a keyhole is a rectangle minus a circle and a blob is two circles that merge on contact. A metaball blend even melts nearby shapes together with a soft neck. They are quick and mathematical. Understanding what they produce, merged forms and cut-out holes, tells you exactly what to recreate here by hand.

2The gap: no liquid-shape booleans

So you never hunt for a phantom button: FoundryInk's vector editor has no liquid-shape boolean modes (no normal, add, subtract, or clip) and no metaball blend. There is no per-shape mode dropdown that merges or cuts one shape against another. If instructions from another program tell you to set a shape to subtract, that step has no equivalent here. Everything below is the supported way to reach the same forms.

3Merge by overlapping filled shapes

To make one merged form from two, simply overlap two filled shapes that share the same fill colour and let them read as a single silhouette. A snowman is three circles overlapping, a cloud is a row of bumps, a cartoon splat is several blobs piled together. Because they share a colour, the eye sees one shape, not three. This is the everyday way to build organic, blobby forms out of simple pieces.

4Hide the seams where they overlap

Overlapping shapes can leave outline seams where their edges cross inside the merged form. If your shapes have outlines, use Hidden Edge to hide the edge segments that fall inside the silhouette, so only the outer contour keeps its line. The result is a single clean outline around the whole merged form, with no stray lines cutting across the middle. This is the finishing touch that sells the merge.

5Cut a hole: leave the inner curve out of the fill

Here is the move that replaces subtract. To cut a hole in a shape (a donut, a washer, a letter O), draw both the outer outline and an inner curve, but when you stage the shape with Create Shape, leave the inner curve out of the fill. An unstaged inner curve reads as a hole, so the fill wraps around it and the middle stays empty. You made a subtraction by simply not filling the centre.

6A worked example: the donut

Here is the classic donut. Draw a big circle for the outer edge and a smaller circle inside it for the hole, both closed with four points and rounded using Smooth. Pick Create Shape, click only the outer circle so it stages amber, and press Fill shape. The inner circle stays a line and reads as a hole, and you have a donut. Style the ring in the Shape style panel and it is done.

7A worked example: a keyhole or letter

The same trick makes any cut-out. For a keyhole, draw the outer plate outline and an inner keyhole curve, then stage and fill only the outer, leaving the keyhole shape unstaged so it punches through. For a letter like O, D, or A, the counter (the enclosed space) is just an inner curve you leave out of the fill. Any shape with a hole in it is an outer boundary filled around an unstaged inner curve.

8Clip by stacking a cover shape on top

To fake a clip, where one shape hides part of another, you stack rather than subtract. Draw a shape to cover the part you want hidden, give it the background colour (or place it so it reads as empty space), and Raise it above the shape underneath. It masks that region visually by sitting on top of it. It is a cover-up rather than a true cut, but on screen the result is identical.

9Raise and Lower are your assembly line

Combining shapes lives and dies by stacking order, so Raise and Lower are your main controls. They move a selected shape up or down the order, deciding which piece sits in front. A merged form wants its pieces at the right depth, a cut-out cover wants to be on top, and a merged blob wants a consistent order so seams tuck cleanly. Get comfortable nudging shapes up and down until the assembly reads correctly.

10Merge and cut in the same form

Real objects often need both at once. A cartoon gear is a merged body (several overlapping shapes) with a cut centre (an unstaged inner curve) and teeth built from more overlaps. Build it in layers: merge the base form with overlapping filled shapes, cut the hole by leaving the inner curve out of the fill, then Raise details on top. Thinking in merge, then cut, then stack lets you construct surprisingly complex forms from simple parts.

11How this behaves when you rig

Because your combined form is really several shapes, rigging respects each piece. Bind all the shapes of one merged form to the same bone and they move together as one, keeping the merge intact as the character animates. A cut-out hole stays a hole because the inner curve travels with the shape it belongs to. You get animation-friendly forms that hold together, as long as related shapes share a bone.

12What good looks like

A well-combined form has clear tells. A merge reads as one silhouette with a single clean outer outline and no stray internal seams, thanks to Hidden Edge. A hole is crisp and empty because the inner curve was left unstaged, not painted over. And the whole assembly holds its shape when rigged because related pieces share a bone. Hit those and your hand-built forms are indistinguishable from boolean ones.

Combining questions