Spiral Tool

Settings

The following settings can be adjusted from the context toolbar:

• Keep selected—when enabled (default), the new shape layer will be selected on creation. When disabled, the new object is deselected which prevents it from adopting the next object’s stroke/fill properties.
• Style—select a spiral style for a different look—this can be done in advance of spiral creation or to swap the spiral to another style at any time. (See examples above.)
  • Linear—this basic spiral creates an even gap between each spiral turn when the arc angle is >90°; angles exceeding this will create an increasingly uneven look to the spiral the greater the angle. The spiral is drawn inwards towards the spiral centre. Settings are:
    • Arc angle—sets the angle to which all arcs on the spiral will conform to.
    • Inner radius—moves the inner spiral start position out from the object centre.
  • Decaying—the gap between each spiral turn decreases the nearer the curve gets to the spiral centre. This is controlled by a Decay value. Settings are:
    • Arc angle—sets the angle to which all arcs on the spiral will conform to.
    • Decay—sets the percentage decay rate along the spiral from the outer end of the spiral to the spiral centre.
    • Decay per turn—the decay rate set by the Decay value is calculated across a full turn.
    • Decay per arc—as for Decay per turn but the calculation is made across an arc rather than a full turn.
    • Minimum radius—sets the least amount that the spiral can decay to at its centre.
    • Cap inside with circle—when enabled, a circular cap is used to terminate the inner end of the spiral. When disabled, the inner end of the spiral will remain open.
  • Semi-circular—like a Linear spiral but the spiral is composed of semi-circular arcs that double in size as they are drawn outwards from the spiral centre; they only have a customisable number of turns.
  • Counter semi-circular—like a semi-circular spiral but the spiral doubles back on itself, creating a spiral with two 'tails'.
  • Fibonacci—the spiral approximates the golden spiral using quarter turn angles derived from the Fibonacci sequence (0,1,1,2,3,5,8,13); the spiral is drawn out from its centre.
  • Plotted—this mathematically calculated 'true' spiral has linear lines, called divisions, between points. Settings are:
    • Divisions—sets the number of straight-lined divisions on the spiral per turn.
    • Inner radius—moves the inner spiral start position out from the object centre.
    • Bias—controls arc distribution along the spiral by setting the interpolation bias of the spiral.
• Use cusped segments—when enabled, the spiral will have straight lines between points. When disabled (default) the spiral is a continuous curve that winds outwards from the spiral centre.
• Spiral clockwise—the spiral winds in a clockwise direction.
• Spiral anti-clockwise—the spiral winds in an anti-clockwise direction.
• Turns—increases or decreases the number of winding turns between the start and end of the spiral, counted from the spiral centre.
• Angle of partial turns—applies the angle to the outside of an arc to add the partial turn. Use for fine control of spiral at ends.
• Convert to Curves—converts the selected object into a series of connected lines and nodes.