Shapes & Cuts

In Voxel mode a form is blocked out from simple solids. The ten shapes are in the Shapes accordion at the top of the Voxel sidebar, six to a row (hover a button for its name). You draw each one straight into a Top, Front or Side view, then decide in the Voxel Tree whether it adds material or cuts it away.

Adding a shape

Click a shape button to arm it. Nothing is added yet: the button stays lit and the Numeric window opens, ready to show the new shape's numbers. Now drag in a Top, Front or Side view. The drag sets the shape's footprint, and the view you draw in becomes the shape's top — so a cylinder drawn in the Front view lies pointing at you. Drawing only works in those flat views; the perspective view has no plane to draw on.

While dragging	What it does
Ctrl	Makes every dimension equal — a perfect cube, sphere and so on.
Shift	Keeps the shape kind's own proportions (a cylinder stays as tall for its width as a fresh one), growing with the drag.
Alt	Held when you press, draws out from the centre instead of from a corner.

Ctrl and Shift are read live, so you can press or release them mid-drag. While a draw tool is armed, Alt belongs to the drawing rather than the camera.

The new shape stays a draft until you finish it. Corner brackets and face diamonds frame it: drag one to resize that corner or side. A press anywhere else in a flat view moves the side of the draft nearest to it out to the press, so you can size it by clicking where its edges should be. Its position, size and rotation can also be typed in the Numeric window.

Click Apply in the Numeric window, or press Return, to finish the shape. The tool stays armed, so the next drag draws another. Click the lit shape button again, or press Esc, to put the draw tool away.

Add and Cut

Every new shape adds: it joins the solid. To make it cut instead, use the button on its row in the Voxel Tree. It shows + for Add; click it to switch to Subtract (−), and again for Intersect, then back to Add.

Mode	What it does
Add (+)	Joins this shape to everything under it.
Subtract (−)	Cuts this shape out of everything under it in the tree. Nothing beside or above it is affected.
Intersect	Keeps only where this shape and everything under it overlap.

A cut works downward: it carves the shapes nested inside it. To cut a hole in a box with a sphere, set the sphere to Subtract, then drag the box's row onto the middle of the sphere's row in the Voxel Tree to put it inside. (Dropping on the top or bottom edge of a row reorders instead.) Because a cut never reaches sideways or up, you can move a whole branch elsewhere without changing what it looks like.

A cutter has no surface of its own, so it is hard to see what you are placing. With a Subtract node selected, press Tab (by default) to outline it in red; press it again to hide the outline.

Blending where shapes meet

By default shapes meet at a hard crease. To round the joint, open Edit Node for the shape (the pen button on its Voxel Tree row) and raise Blend. It rounds the joint where this node meets what it touches — both its own children and its siblings — so a limb flows into a body instead of being stuck on. On a cutter it softens the edge of the hole. 0 leaves a hard crease.

Blend rounds the joints between shapes. To round a shape's own edges, use its own settings below: a box's Corner radius, or a cylinder's Soft Rims, each with a Chamfer option for a straight 45-degree bevel instead of a round.

The shapes and their settings

Every shape has a width, height and depth, which mean slightly different things per kind (shown below). Several shapes also have settings of their own. These appear in the Numeric window while you draw, and whenever the shape is selected without Move, Rotate or Scale on. A shape with nothing more to set says so.

Shape	Size	Its own settings
Box	Width, height and depth.	Corner radius rounds every edge; tick Chamfer for a bevel instead.
Sphere	Diameter on each axis. Equal values give a sphere; unequal give an ellipsoid.	None.
Cylinder	X and Z are the base diameters, Y is the height.	Soft Rims rounds the two rims, by Rim radius (or a bevel with Chamfer). Wall makes it a hollow tube open at both ends, with a Wall thickness.
Cone	X and Z are the base diameters, Y is the height. The point is at the top.	None.
Capsule	X and Z are the diameters, Y is the total height including both rounded ends. Below one diameter tall it becomes a sphere.	None.
Round Cone	A tapered capsule: X is the bottom diameter, Z the top diameter, Y the total height.	Depth: how deep it is front to back, as a percentage of its width. 100% is round; drawing a long footprint stretches it into an oval.
Torus	X is the overall diameter across the ring, Y the tube diameter. The ring lies flat.	See Torus below.
Pyramid	X and Z are the base, Y is the height. The point is above the centre of the base.	None.
Prism	A regular prism with a set number of sides.	The number of sides (3 to 64), and X, Y or Z: the axis the flat top and bottom face.
Gear	A spur gear.	See Gear below.

Torus

Control	What it does
Start angle, End angle	How far round the ring goes, in degrees — less than a full circle gives an arc.
Diameter, Tube diameter	The overall size of the ring, and the thickness of the tube.
Ring sides, Tube sides	3 to 16 straight segments round the ring, or sides to the tube. Any other number, or “round”, makes it round.
Ring rotation, Tube rotation	Turn the ring's corners about the torus's centre axis, or the tube's cross-section about its centre line (45 makes a square tube a diamond). Only for a ring or tube with sides.
Outer corners, Inner corners	How round a polygonal ring's outside and inside corners are: 0% sharp, 100% rounded by the whole tube radius.
Tube twist (turns)	How many times a polygonal tube's cross-section turns over one trip round the ring. A whole number of sides' worth (0.25 for a square) joins up cleanly.

Gear

Control	What it does
Axis	X, Y or Z: which way the gear's flat faces point.
Number of teeth	3 to 256.
Inner radius	The root circle the teeth stand on.
Taper %	How much narrower each tooth is at its tip than at its root. 0% gives straight-sided teeth.
Outer radius	To the tips of the teeth.
Thickness	How thick the gear is along its axis.
Smooth teeth	Rounds the tips and fillets the roots.
Center hole	Cuts a round hole through the middle, sized by Hole diameter. The hole always stays smaller than the inner radius, so the ring the teeth stand on is never cut through.

Offset and Shell

Two buttons in the Transform accordion change finished shapes. Select one or more shapes first, then click a button; the Numeric window opens on that tool's page and the result previews as soon as you enter an amount.

Control	What it does
Offset	Grows each selected shape outward by this much, or shrinks it with a negative value.
Shell	Hollows each selected shape to a wall this thick. 0 keeps it solid.

Apply or Return keeps the result; Esc, or clicking the button again, drops it. Both work on shapes, not groups: with a group selected the page asks you to flatten it first, so it is offset or shelled as one shape, and offers a Flatten button to do it. Locked nodes are left alone.

Colours and materials

A shape's colour comes from its material, set under Material in Edit Node. Materials are named and shared, so changing one recolours every node that uses it. A node with no material of its own takes its parent's, shown as (from parent) in the list.

Control	What it does
Colour swatch	The colour of the material this node uses. Changing it on a node with no material of its own gives that node a new material, rather than recolouring the parent.
Material list	Pick an existing material, or (none).
New	Creates a new material for this node and lets you name it; press Enter to finish. It starts with the colour the node shows now.
Colored Cuts	Only for a node set to Subtract. On: the faces it cuts take its colour. Off: they keep the colour of what was cut. Useful to paint a groove or a socket a different colour.
Uncuttable	Nothing can cut into this node or anything under it — a Subtract passing through it leaves it whole.