// Image PopUp II (29-May-2006)
// by Vic Phillips http://www.vicsjavascripts.org.uk
// An alternative to the Standard PopUp to display an Image
// The PopUp is sizes to the displayed image and cannot be blocked.
// An optional TitleBar displays a default or specified title
// and allows the PopUp to be Drag and Dropped to a new position
//
// An optional message panel may display a message below the image.
//
// The appearance of the PopUp may be customised using Customising Variables.
// The PopUp Image may be its natural or a specified size.
//
// The PopUp is normally populated with an image and displayed by an onclick event
// and hidden be clicking outside the event object or the title 'X' box.
// Optional Code allows:
// Positioning a opaque mask under the Image PopUp
// To Center the Image PopUp in the window
// Application Notes
// **** Initialisation
//
// The Image PopUp is initialised from a or window onload event
// e.g.
//
//
// Activating the Image PopUp
//
// The PopUp is normally populated with an image and displayed by an onclick event
//
// 
// where:
// parameter 0 = The PopUp position anchor object or unique ID name. (string or object)
// parameter 1 = the horizontal(X) offset from the anchor object. (digits)
// parameter 2 = the vertical(Y) offset from the anchor object. (digits)
// parameter 3 = the directory path and file name of the image to be displayed. (string)
// parameter 4 = (optional) the text to be displayed in the title(null if the title bar is not required). (string or null)
// parameter 5 = (optional) an array to force the image to a specified. (an array of two digits or null)
// field 0 = width,
// field 1 = height.
// parameter 6 = (optional) an array to define a message panel. (an array of two strings or null)
// field 0 = the style class name to apply to the message panel,
// field 1 = the message HTML code.
//
// **** The Title Bar
//
// The optional Title Bar is displayed if parameter 5 of function call to 'zxcImgPopUpII(' is completed.
// The string specified in parameter 5 will be displayed in the title bar
// unless only one character is specified, in which case the Default Title will be displayed.
// **** Drag and Drop
//
// The Image may be Dragged and Dropped from the Title Bar
// The Initial position is specified by the event call to display the image.
// Once repositioned this position is updated for the next time the image is displayed.
//
// ***** Opacity Mask
//
// Image PopUp II Part 2 is required for this options
//
// An Opacity Mask may be placed under the Image PopUp.
// This 'Mask' is dimensioned to the current window and the opacity, color and background image specified.
//
// The 'Mask' will not be displayed in browsers which do not support opacity
//
// ** A Default 'Mask'
//
// A default 'Mask' is initialised from a or window onload event
// and called after the 'zxcInitImgPopUpII()' call.
// e.g.
//
// where function 'zxcInitMask('
// parameter 0 = the opacity. (digits 1 to 99)
// parameter 1 = (optional) the back ground color. (string, a valid color or '' if not required)
// parameter 2 = (optional) the back ground image. (string, a valid image file name or omit if not required)
//
// An Object 'Mask'
//
// Specific instances of an Image PopUp may be assigned a 'Mask'
// This 'Object Mask' will have precedence over the 'Default Mask'
// The 'Object Mask' is activated be the same call as the Image PopUp call
// e.g.
// 
// where function 'zxcInitMask('
// parameter 0 = The PopUp position anchor object or unique ID name. (string or object)
// parameter 1 = the opacity. (digits 1 to 99)
// parameter 2 = (optional) the back ground color. (string, a valid color or '' if not required)
// parameter 3 = (optional) the back ground image. (string, a valid image file name or omit if not required)
//
// **** To Center the Image PopUp in the window
//
// Image PopUp II Part 2 is required for this options
//
// The Image PopUp would normally be positioned relative to the object specified
// in parameter 0 of the activating call 'zxcImgPopUpII('
//
// To center the Image PopUp in the current window this parameter must be specified a 'C'
// e.g.
//
//
// **** General
//
// All variable, function etc. names are prefixed with 'zxc' to minimise conflicts with other JavaScripts
// These characters may be changed to characters of choice using global find and replace
//
// The Functional Code Part 1 (about 7K) and Part 2 (about 2.5K) are best as External JavaScripts.
// The Functional Code size may be reduced by including only the required functions.
//
// Tested with IE6 and Mozilla FireFox