C#: Create a lighter/darker color based on a system color

Duplicate

How do I adjust the brightness of a color?
How do I determine darker or lighter color variant of a given color?
Programmatically Lighten a Color

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Say I have

var c = Color.Red;

Now I want to create a new Color that is lighter or darker than that color. How can I do that without too much hassle?

From stackoverflow

• Using HSI converter library(search google). And then, adjust I channel for lighter/darker color.

• ControlPaint.Light .Dark .DarkDark, etc.

  Color lightRed = ControlPaint.Light( Color.Red );
  

  schnaader : corrected your typo, although a ControlPain class would be funny :)

  Paul Alexander : hehe...if you've every done any you know how true that is.

  Svish : ControlPaint.Light and .Dark are perfect :D Especially with the extra percentage float parameter thingy.

  Soul_Master : Today, I realize that .Net framework is very huge size. Because I don't know about ControlPaint class before. But I use only 3-party image processing(like AForge.net). Thanks.

• Take a look at the ControlPaint class:

  MSDN: Members of ControlPaint

• Here's some javascript code I use for lightening/darkening a given colour. You could use it as a base for an equivalent C# function

  It works by calculating a distance from pure white of each of the RGB components and then adjusts this distance by the provided factor. The new distance is used to calculate the new colour. A factor of between 0 and 1 darkens, a factor higher than 1 lightens

  function Darken( hexColor, factor )
      {   
          if ( factor < 0 ) factor = 0;
  
          var c = hexColor;
          if ( c.substr(0,1) == "#" )
          {
              c = c.substring(1);
          }
  
          if ( c.length == 3 || c.length == 6 )
          {
              var i = c.length / 3;
  
              var f;  // the relative distance from white
  
              var r = parseInt( c.substr(0, i ), 16 );
              f = ( factor * r / (256-r) );
              r = Math.floor((256 * f) / (f+1));
  
              r = r.toString(16);
              if ( r.length == 1 ) r = "0" + r;
  
              var g = parseInt( c.substr(i, i), 16);
              f = ( factor * g / (256-g) );
              g = Math.floor((256 * f) / (f+1));
              g = g.toString(16);
              if ( g.length == 1 ) g = "0" + g;
  
              var b = parseInt( c.substr( 2*i, i),16 );
              f = ( factor * b / (256-b) );
              b = Math.floor((256 * f) / (f+1));
              b = b.toString(16);
              if ( b.length == 1 ) b = "0" + b;
  
              c =  r+g+b;
           }   
  
           return "#" + c;
  
      }
  

• You can also do this using a Lerp function. There's one in XNA, but it's easy to write yourself.

  See my answer to this similar question for a C# implementation.

  The function lets you do this:

  // make red 50% lighter:
  Color.Red.Lerp( Color.White, 0.5 );
  
  // make red 75% darker:
  Color.Red.Lerp( Color.Black, 0.75 );
  
  // make white 10% bluer:
  Color.White.Lerp( Color.Blue, 0.1 );