Draw Strands Tool
The Draw Strands tool lets you create and shape guides by drawing directly on the distribution surface. Instead of relying only on procedural distribution, you place guides exactly where you want them and define their shape by hand - useful for art-directed hairlines, stray strands, and precise placement.
Drawing guides
The tool responds to how you interact with the surface:
- Single click plants a new guide at that point, with its shape interpolated from the neighbouring guides so it fits in with the surrounding hair.
- Click and drag on an empty part of the surface draws a new guide along your stroke, so the path you trace defines the guide's shape. The stroke is traced in the viewport as you drag, and the guide appears when you release the mouse.
This lets you both fill in guides that match their neighbours and lay down entirely new shapes where there are none.
Draw Strands settings
The Draw Strands rollup sets what a stroke does and how the guide it leaves is built.
- Create New Strands lets a stroke on an empty part of the surface draw a new guide. With it off, strokes only reshape guides that are already there.
- Edit Existing Strands lets a stroke that starts on a guide reshape that guide instead of drawing a new one over it. A guide that is hidden behind the distribution surface from the current view is not picked up this way; a new guide is drawn at the surface instead.
- Select Edited Strands, on by default, makes the guide you just drew or reshaped the current selection, shown in the selection colour, so you can carry on with the Edit Strands tools right away without picking it first. Turn it off to keep the selection you had.
- Point Count is the number of control points of a newly drawn guide. The stroke is resampled to that count, evenly along its length.
- Maximum Length caps the length of a drawn guide: a longer stroke is cut off at that length from the root.
- Use Smoothing and Smoothness smooth the drawn curve once the stroke is finished, taking out the jitter of a hand-drawn line. Turn smoothing off to keep the stroke exactly as drawn.
Symmetry
Symmetry Axis in the Symmetry Settings rollup mirrors every drawn guide across the chosen axis of the object, so a stroke on one side of the head draws its counterpart on the other side as well. Off, the default, draws on one side only.
Starting without an Edit Guides operator
You do not need to add an Edit Guides operator before you draw. With any operator that outputs a mesh, guides or hair selected, the tool shows its surface marker on the surface the guide would be planted on - the mesh itself, or the distribution surface of the hair - and the first stroke adds an Edit Guides operator on top of the selected operator and draws into it. Later strokes keep working with that operator. When you start from a mesh, the mesh keeps a display node of its own so it stays visible while its original display node shows the new guides. The stroke and the added operator are one undo step, and undoing them leaves the Draw Strands tool active.
Inheriting from nearby guides
A guide drawn next to existing ones picks up their look instead of starting from defaults. It takes the strand group, the per-vertex and per-strand channel data, the widths and the rotation of the closest guide, with anything stored per vertex resampled onto the drawn guide's own points. Each of the four is a separate option in the tool settings and all of them are on by default, so you can turn off any part you would rather set yourself.
Starting a new strand group
Press Shift+Q, or the New Strand Group button in the Inherit From Closest Guide rollup, to put the next guide you draw into a new, unused strand group instead of the group it would inherit. The button shows while the action is armed. It applies to one drawn guide: the guides you draw next to it afterwards inherit its group, so a group is started with one press and then filled by drawing. Reshaping an existing guide does not use it up, and a mirrored guide joins the same new group. Press Shift+Q again to disarm it, or hold it to arm it only for as long as it is held. The shortcut works only while the Draw Strands tool is active.
Keeping strokes off the surface and other objects
A stroke is drawn at the depth of its root, so a guide drawn across the head or another object in the viewport runs straight through it. Two groups of settings keep the drawn guide where it belongs.
Base Collision
These settings concern the surface the guides are kept along: the character mesh of the edited hair when it has one (see the Character Mesh input of the Edit Guides Operator), otherwise its distribution mesh. The root is always planted on the distribution mesh.
- Conform To Surface makes the drawn curve follow the surface curvature instead of staying at the root's depth.
- Distance from Surface is how far above the surface the conforming curve is kept.
External Collision
These settings place the guide against other objects. The guide's own distribution mesh and its character mesh are never part of them; the Base Collision settings handle them.
- Collider picks the surfaces: None draws without collision, All uses every other mesh shown in the viewport, or pick one of the scene's meshes by name. A mesh picked by name keeps colliding while it is hidden, so you can hide a garment to see the guides and still draw around it.
- Use Depth, on by default, places each point of the guide by Depth rather than by Collision Distance.
- Depth is where the guide lies between the base surface under the cursor (0) and the collider surface (1), as seen from the view. The default of 1 lays the guide on the collider; 0.5 hangs it half way between the two surfaces, which is the way to draw hair under a hair shell or a garment; values above 1 push it out beyond the collider by the same measure again. A collider behind the distribution mesh is ignored, and where the cursor leaves the distribution mesh its last depth carries on.
- Collision Distance applies when Use Depth is off: how far from the collider surface the guide is kept, measured along the surface normal. A positive value keeps it outside the collider; a negative value lets it sink that far into the collider. Points of the stroke which already sit in front of the colliders are left where they were drawn.
- Collision Blend is the point along the guide, from root (0) to tip (1), from which the collision fully determines the curve. Up to there the depth ramps up from the distribution mesh, or the collided curve is blended with the drawn one, so the root stays on the distribution surface and the guide bends smoothly out to the collider.
- Avoid Jumps, on by default, keeps the guide on the collider surface it is on. Without it every point of the stroke is placed against whatever the cursor is over, so a stroke that strays off a dread onto the one behind it, or off the hair mesh altogether, makes the guide jump in depth with it. With it, a point whose collider surface lies far from the previous point's - across a gap or a fold - is instead continued from the previous point by the cursor's move and placed on the nearest collider surface, so the guide hugs the side of the shape it is on. A stroke which leaves the colliders entirely stays at their edge; turn the option off to draw such a guide into the open.
Working with the stack
Drawn guides become part of the groom through the Edit Guides Operator, so they are recorded procedurally and can be refined later with brushes or operators. After drawing, generate dense hair from the guides with Hair from Guides Operator as usual.
Related
- Edit Guides Operator - refine drawn guides with brushes and selection.
- Brush Tools - the Create brush also plants guides as you brush.
- Working with the Grooming Tools - the full set of interactive tools.