Color/Tutorials

Predefined colors

The following predefined colors are loaded in ConTeXt (see colo-imp-rgb.mkiv).

Name	Color	Name	Color	Name	Color	Name	Color
black		white
gray		lightgray		middlegray		darkgray
red		lightred		middlered		darkred
green		lightgreen		middlegreen		darkgreen
blue		lightblue		middleblue		darkblue
cyan				middlecyan		darkcyan
magenta				middlemagenta		darkmagenta
yellow				middleyellow		darkyellow

Other Predefined colors can be loaded.

Use predefined colors

To color text, use \color or \startcolor

\color[defined-color]{ ... text ... }

\startcolor[defined-color] 
   ... text ... 
\stopcolor

where defined-color is a color defined using \definecolor. For example, darkred is one of the predefined colors. So, we can use:

• Three \color[darkred]{cool} cats
  

• 

or

• \setuppapersize[A7]
  \setupalign[tolerant]
  
  \definecolor
    [brightorange]
    [c=0, m=.4325, y=.9286, k=.0118]
  
  \starttext
  
  \startcolor[darkred]
  \input tufte
  \stopcolor
  
  \startcolor[brightorange]
  \input tufte
  \stopcolor
  
  \stoptext
  

• 

Use color components

It is also possible to use RGB or CMYK or hex values to color text. The syntax for these is

\colored[settings]{... text ...}

where settings are the same settings as used by \definecolor. For example:

• Three \colored[r=0.1, g=0.8, b=0.8]{colorful} cats
  

• 

Commands with color option

Often, there is no need to use the color commands directly. Almost all ConTeXt commands accept a color key, and you can use color=defined-color. For example,

• To color the section titles red, use

\setuphead[color=red]

• To color the footnotes red, use

\setupfootnotes[color=red]

etc…

Changing color of an entire document

To change the main text color of the document use

\setupcolors[textcolor=defined-color]

For example,

• \setuppapersize[A8,landscape]
  
  \definecolor[bluu][r=.25, g=.1, b=1]
  \setupcolors[textcolor=bluu]
  
  \starttext
  \input tufte
  \stoptext
  

• 

Changing background color of page

The background color of the page can be changed using

\setupbackgrounds[page][background=color,backgroundcolor=defined-color]

• \setuppapersize[A8,landscape]
  
  \definecolor[bluu][r=.25, g=.1, b=1]
  \setupbackgrounds
    [page]
    [background=color,
     backgroundcolor=bluu]
  \setupcolors[textcolor=white]
  
  \starttext
  \input tufte
  \stoptext
  

• 

Disabling color in a document

\setupcolors[state=stop]

Highlighting words

It’s usually bad style to use explicit color switches in the text. It’s better to define a semantic command that takes care of the color switching. For example, instead of using \color[red]{important text}, define

• \definehighlight[important][color=red]
  
  This is an \important{important text} here.
  

• 

Using colors in MetaPost

A color defined in TeX is available in MetaPost using \MPcolor.

• \definecolor[highlight][r=0.8,g=0.8,b=0]
  
  \color[highlight]{Highlighted text in TeX}
  
  \startMPcode
  label("Highlighted text in MetaPost", origin)
      withcolor \MPcolor{highlight};
  \stopMPcode
  

• 

Note that \MPcolor{...} behaves similar to a color primitive in MetaPost. For example, the following is valid MetaPost code.

color myColor; myColor = 0.5[\MPcolor{highlight}, white];

For more further reading: Color in MetaPost.

Defining palettes and switching

Colors can be grouped in palettes with \definepalet. The colors in such a palette can have colorful names, but best is to use names that specify their use, like important or danger.

The palette can then all be activated at once with \setuppalet.

To inspect the palet, or to compare its colors against each other, use \showpalet and \comparepalet.

• \setuppapersize[A8]
  \usecolors[x11]
  \definepalet
    [versionA]
    [alert=green,contrast=orange]
  \definepalet 
    [versionB]
    [alert=darkgray,contrast=lightgray]
  \starttext
  
  \setuppalet  [versionA]
  \color[alert]{Alerting color}\\
  \color[contrast]{Contrasting color}
  
  \blank[line]
  
  \setuppalet  [versionB]
  \color[alert]{Alerting color}\\
  \color[contrast]{Contrasting color}
  
  \blank[line]
  
  \showpalet [versionA] [vertical,name,number]
  \comparepalet [versionA]
  
  \blank[line]
  
  \showpalet [versionB] [vertical,name,number]
  \comparepalet [versionB]
  \stoptext
  

• 

External references

• Paletton - website to choose color palettes
• ColorBrewer - website to choose colors for maps and graphics
• The Complete Color Harmony, Tina Sutton, Bride M Whelan. Rockport Publishers (2004). ISBN 978-1592530311 (recommended in the mailing list)
• Color-wheel from color.adobe.com