color_helper.php

apache windows下的一款好

                                "SlateGray" => array(112,128,144),
                                "Snow" => array(255,250,250),
                                "SpringGreen" => array(0,255,127),
                                "SteelBlue" => array(70,130,180),
                                "Tan" => array(210,180,140),
                                "Teal" => array(0,128,128),
                                "Thistle" => array(216,191,216),
                                "Tomato" => array(255,99,71),
                                "Turquoise" => array(64,224,208),
                                "Violet" => array(238,130,238),
                                "Wheat" => array(245,222,179),
                                "White" => array(255,255,255),
                                "WhiteSmoke" => array(245,245,245),
                                "Yellow" => array(255,255,0),
                                "YellowGreen" => array(154,205,50)
                        );
                        
                        
    /**
    * Translates a userdefined color specification into an array of RGB integer values.
    * 
    * Several formats can be handled. HTML like hexadecimal colors like #f0ff00, 
    * names colors, arrays of RGB integer values and strings with percentage values
    * like %100,%50,%20. If the format is unknown black gets returned [0, 0, 0].
    * 
    * @var      mixed   Color in various formats: #f0f0f0, %20,%100,%0, 
    *                   named - black, white..., [int 0 - 255, int 0 - 255, int 0 - 255]
    * @return   array   RGB color [int red, int green, int blue]
    * @access   public
    * @see      $colornames, HTMLColor2RGB(), PercentageColor2RGB(), NamedColor2RGB()
    */                        
    function color2RGB($color) {
    
        if (is_array($color)) {
            
            // looks good...
            if (3 == count($color)) {
            
                // check the range
                foreach ($color as $k => $v) {
                    if ($v < 0)
                        $color[$k] = 0;
                    else if ($v > 255) 
                        $color[$k] = 255;
                    else 
                        $color[$k] = (int)$v;
               }
                
               return $color;        
            }
                

            // unknown format - return black
            return array(0, 0 , 0);
        }

        // #f0f0f0            
        if ("#" == $color{0})
            return $this->HTMLColor2RGB($color);

        // %50,%100,%50
        if ("%" == $color{0})
            return $this->PercentageColor2RGB($color);

        // might be a color name            
        return $this->NamedColor2RGB($color);
    } // end func color2RGB     
    
    
    /**
    * Allocates a color in the given image.
    * 
    * Userdefined color specifications get translated into 
    * an array of rgb values.
    *
    * @param    resource    Image handle
    * @param    mixed       (Userdefined) color specification
    * @return   resource    Image color handle
    * @see      color2RGB()
    * @access   public
    */  
    function allocateColor(&$img, $color) {
        
        $color = $this->color2RGB($color);
        
        return ImageColorAllocate($img, $color[0], $color[1], $color[2]);
    } // end func allocateColor                  
    
    /**
    * Returns the RGB integer values of an HTML like hexadecimal color like #00ff00.
    *
    * @param    string  HTML like hexadecimal color like #00ff00
    * @return   array   [int red, int green, int blue],
    *                   returns black [0, 0, 0] for invalid strings.
    * @access   public
    */
    function HTMLColor2RGB($color) {
        if (strlen($color) != 7)
            return array(0, 0, 0);

        return array(
                        hexdec(substr($color, 1, 2)),
                        hexdec(substr($color, 3, 2)),
                        hexdec(substr($color, 5, 2))
                    );
    } // end func HTMLColor2RGB    
    
    
    /**
    * Returns the RGB interger values of a named color, [0,0,0] if unknown.
    *
    * The class variable $colornames is used to resolve
    * the color names. Modify it if neccessary. 
    *
    * @param    string  Case insensitive color name.
    * @return   array   [int red, int green, int blue], 
    *                   returns black [0, 0, 0] if the color is unknown.
    * @access   public
    * @see      $colornames
    */
    function NamedColor2RGB($color) {
        $color = strtolower($color);
        
        if (!isset($this->colornames[$color]))
            return array(0, 0, 0);
          
        return $this->colornames[$color];
    } // end func NamedColor2RGB 
    
    
    /**
    * Returns the RGB integer values of a color specified by a "percentage string" like "%50,%20,%100". 
    *
    * @param    string
    * @return   array   [int red, int green, int blue]
    * @access   public
    */
    function PercentageColor2RGB($color) {
        
        // split the string %50,%20,%100 by ,
        $color = explode(",", $color);        
                
        foreach ($color as $k => $v) {
        
            // remove the trailing percentage sign %
            $v = (int)substr($v, 1);
            
            // range checks
            if ($v >= 100) {
                $color[$k] = 255;
            } else if ($v <= 0) {
                $color[$k] = 0;
            } else {
                $color[$k] = (int)(2.55 * $v);
            }
            
        } 

        return $color;
    } // end func PercentageColor2RGB
    
    
} // end class ColorHelper
?>