Utility Function of the Day

The following method mixes several colors together according to a specified bias thus creating a new color. It is a very useful function for custom user-interface components, especially if they are to be affected by user-customization.

For example:
Consider a calendar-widget that has different color codes for different types of holidays (by religion perhaps). You can use this function to calculate the selection color for a specific day by mixing the global (user-chosen?) selection color with the specific day's color and even to go further and to mix several colors when holidays intersect.

How it works:
The specified Color objects are split to their individual color-components or channels (red, gree, blue and alpha) which are then collected while being multiplied by the per-color bias. Then, an average value for each color component is calculated based on the collected channels and used to create a new Color object.

Note:
Make sure to remember to cache the resulting Color object for re-use whenever possible! Object-Creation-Is-Expensive(tm).

The Code:

  public  static  Color mixColors(Color[] colorsToMix,  float[] colorBias)

  {

    long  red   = 0;

    long  green = 0;

    long  blue  = 0;

    long  alpha = 0;



    for (int  i = 0;  i < colorsToMix.length; i++)

    {

      Color currentColor  = colorsToMix[i];

      float currentBias   = colorBias[i];



      red   +=  currentColor.getRed()   * currentBias;

      green +=  currentColor.getGreen() * currentBias;

      blue  +=  currentColor.getBlue()  * currentBias;

      alpha +=  currentColor.getAlpha() * currentBias;

    }



    red   /=  colorsToMix.length;

    green /=  colorsToMix.length;

    blue  /=  colorsToMix.length;

    alpha /=  colorsToMix.length;



    return  new Color((int)red,  (int)green,  (int)blue,  (int)alpha);

  };

Enjoy!