Key |
Type |
Value |
---|---|---|
Coords |
array |
(Required) An array of six numbers [ x 0 y 0 r 0 x 1 y 1 r 1 ] specifying the centres and radii of the starting and ending circles, expressed in the shading’s target coordinate space. The radii r 0 and r 1 shall both be greater than or equal to 0. If one radius is 0, the corresponding circle shall be treated as a point; if both are 0, nothing shall be painted. |
Domain |
array |
(Optional) An array of two numbers [ t 0 t 1 ] specifying the limiting values of a parametric variable t. The variable is considered to vary linearly between these two values as the colour gradient varies between the starting and ending circles. The variable t becomes the input argument to the colour function(s). Default value: [ 0.0 1.0 ]. |
Function |
function |
(Required) A 1-in, n-out function or an array of n 1-in, 1-out functions (where n is the number of colour components in the shading dictionary’s colour space). The function(s) shall be called with values of the parametric variable t in the domain defined by the shading dictionary’s Domain entry. Each function’s domain shall be a superset of that of the shading dictionary. If the value returned by the function for a given colour component is out of range, it shall be adjusted to the nearest valid value. |
Extend |
array |
(Optional) An array of two boolean values specifying whether to extend the shading beyond the starting and ending circles, respectively. Default value: [ false false ]. |