Scales

meter.py can draw meter scales using arcs with tickmarks. There can be several scales on a meter label.

Mandatory parameters

• radius

  The radius of the scale arc in mm.

• min_value

  The lowest (left-hand) meter reading. For a scale reading 0-5 this would be 0.0.

• max_value

  The highest (right-hand or f.s.d.) meter reading. For a scale reading 0-5 this would be 5.0.

• function

  The transfer function of the scale. For a linear scale use the provided meter.linear. It is possible to write a custom function for special meters (see Custom Transfer Functions)

Optional parameters and defaults

• show_arc

  Specifies if the line of the arc will be drawn. Default is True.

• scale_stroke

  Specifies the colour of the scale arc. Default is black.

• scale_stroke_width

  Specifies the thickness of the scale arc in mm. Default is 0.1.

• tick_direction

  Specifies the direction of the tick marks on the arc. 1.0 is outwards, -1.0 is inwards. Default is 1.0.