Re: [Gimp-developer] [GIMP] Question on linear and radial gradient

["David Gowers (kampu)" <00ai99 gmail com>]

On Thu, Mar 1, 2012 at 10:40 PM, Forsale Zhangjiang
<forsale_zhangjiang yahoo com> wrote:
> Hello experts,
>
> I am confused by the calls -gimp_linear_gradient and -gimp_radial_gradient
> used in GIMC. My question is, what are their functions respectively?

You'll have to ask the author of G'MIC -- those are functions defined
in GMIC, not GIMP.
If I look in ~/.gmic_def.1500, i can find the following code:

#@gimp Linear gradient : gimp_linear_gradient, gimp_linear_gradient
#@gimp : Starting color = color(0,0,0,255)
#@gimp : Ending color = color(255,255,255,255)
#@gimp : Swap colors = bool(0)
#@gimp : Angle = float(45,0,360)
#@gimp : Fade start = float(0,0,100)
#@gimp : Fade end = float(100,0,100)
#@gimp : sep = separator(), note = note("<small>Author : <i>David
Tschumperl&#233;</i>.      Latest update :
<i>2010/12/29</i>.</small>")
gimp_linear_gradient :
  -repeat @#
    ({w},{h}) -rm[-2]
    ($1^$2^$3^$4) ($5^$6^$7^$8)
    -if $9 -rv[-2,-1] -endif
    -r[-2,-1] @-3 -rm[-3]
    -fade_linear $10,$11,$12
  -mv[-1] 0 -done

#@gimp Radial gradient : gimp_radial_gradient, gimp_radial_gradient
#@gimp : Starting color = color(0,0,0,255)
#@gimp : Ending color = color(255,255,255,255)
#@gimp : Swap colors = bool(0)
#@gimp : Fade start = float(0,0,100)
#@gimp : Fade end = float(100,0,100)
#@gimp : X-center = float(50,0,100)
#@gimp : Y-center = float(50,0,100)
#@gimp : sep = separator(), note = note("<small>Author : <i>David
Tschumperl&#233;</i>.      Latest update :
<i>2010/12/29</i>.</small>")
gimp_radial_gradient :
  -repeat @#
    ({w},{h}) -rm[-2]
    ($1^$2^$3^$4) ($5^$6^$7^$8)
    -if $9 -rv[-2,-1] -endif
    -r[-2,-1] @-3 -rm[-3]
    100%,100% -=[-1] 1,$12%,$13% -distance[-1] 1 -_fade $10,$11
  -mv[-1] 0 -done