Controls number of strands of hair spreading out from the imaginary centerline of a skeletal stroke. Here is a summary of what the sliders and controls do.ģ.1 Spread. This step preserves your skeleton for repeated use.ģ Choose Rendering -> Hair locks. Uncheck 'Preview' - this to avoid unnesseasary rendering until you're ready.Ģ.4. Based on anisotropic smoothing, the behaviour of the Hair lock filter is scale dependent, so unless the preview matches the scale of the active layer, the rendering it performs on the preview bitmap isn't much of a preview of its action on the active layer.Ģ.3. Check that your image view is at 100% and that the preview window is also 100% or 1:1. Check to make sure your skeleton is visible in the preview window. Start the G'MIC plugin (Filters -> G'MIC).Ģ.1. It is not uncommon to vary the parameters somewhat between runs to give the hairlock a diverse character. You then repeat this procedure two, three or four times, producing individual plies that stack up into one hair lock. So your average workflow will have you rendering off a skeleton, making a layer of somewhat translucent hair, then moving, rotating, or applying the Distorts->IWarp native Gimp filter to your skeleton to shift the skeleton a bit for the next ply. The pile of plies, each ply on its own layer, criss-crosses hair strands, which produces a more realistic effect than the unreality of perfectly aligned hair. Almost always, a hairlock consists of a pile of plies - separate renderings - each from slightly modified skeletons. But instead of applying it to the skeleton image, the hairlock filter applies it to internally generated salt-and-pepper noise, turning a lot of little dots into so many hair strands.ġ.5. Behind the scenes, the hairlock filter detects edges and composes a 'smoothing geometry', something designed to blur noise-generated bits without blurring edges. Choose a setting so that hair strands are visible, that is, the highlights or shadows do not block in as contiguous masses.ġ.4. Then hard-edge everything with Colors -> Threshold. Alternately, grab a photograph of a real head of hair and run it through Filters->Enhance->Unsharp Mask, using settings strong enough to make highlights and shadows (almost) indistinguishable.

Use this, or fire up Gimp and quickly scribble some lines with a hard-edge brush or the Pencil tool.ġ.3. This is the skeleton which served as the front hair lock of the woman in Hair lock test image - WASP. The idea is to draw a few master hair strands which will then set the direction of a lot of their siblings.ġ.2. Almost any artwork will serve so long as it exhibits sharp edges and has moderate to high contrast. You start with a 'skeleton', which serves as a template it sets the shape of your hair lock.ġ.1. While the filter is nominally called 'Hair lock', you can render similar long, stringy stuff, such as grass or mop-heads with it. You wish to paint something which looks like hair: clusters (locks) of long, stringy stuff, which exhibit specular properties, such as the way light reflects off of compact disks or (to show my age) phonograph records. The version date on the Hair lock filter should be 1. This tutorial was composed using version 1.6.0.2 Gimp version 2.8.14.

To use this particular filter, you need a Gimp-G'MIC plugin that is at version 1.6.0.0 or better.

A full, but more technical tutorial, lives at G'MIC Hairlock Tutorial on the G'MIC Web site.

Gimp tutorials 2014