====== colorpicker ======

===== Motivation =====
As part of a toolbox with a GUI that supports statistical map overlay, I wanted to have a nice interface to select (pick) colors. Most programs (e.g. Photoshop) have a comparable option.

===== Function reference ('help colorpicker') =====
<file>  colorpicker  - pick a color from the RGB/HSV color space
 
  FORMAT:       color = colorpicker([icolor [, icnames]]);
 
  Input fields:
 
        icolor      initial color or colors (default: [0, 0, 0]);
        icnames     color name(s) (labels)

  Output fields:

        color       Cx3 RGB color (values in the [0...255] range)</file>

===== GUI layout and functionality =====
The general layout is always the same and looks like this:

{{:colorpicker_singlecolor.png|colorpicker with a single color}}

Each of the five areas showing a color-gradient is click-sensitive, which means that by clicking at a given position, the color will change to the color below the mouse cursor.

Additionally, colors can be coded either in the HSV or RGB color space (with a scaling of ''[0 .. 255]'' for each value).

The buttons on the lower right side will
  * reset the color to the values given at call time (Reset)
  * close the dialog without altering the values given at call time (Cancel)
  * close the dialog and return the colors as they were displayed at the time (Accept)

If multiple colors are to be shown (e.g. a palette), names can be given and instead of one uni-colored patch in the top right corner, a grid of colors is presented, which itself is click-sensitive to switch between colors:

{{:colorpicker_palette.png|colorpicker with a palette of colors (colormap 'hot')}}

===== Notes =====
This function requires the [[xfigure]] class to be working properly!