//
// Enumerations for the Fast Light Tool Kit (FLTK).
//
// Copyright 1998-2024 by Bill Spitzak and others.
//
// This library is free software. Distribution and use rights are outlined in
// the file "COPYING" which should have been included with this file.  If this
// file is missing or damaged, see the license at:
//
//     https://www.fltk.org/COPYING.php
//
// Please see the following page on how to report bugs and issues:
//
//     https://www.fltk.org/bugs.php
//

/** \file
    This file contains type definitions and general enumerations.
 */

#ifndef Fl_Enumerations_H
#define Fl_Enumerations_H

/*
 ******************************************************************************
 * FL_ABI_VERSION is defined by configure or CMake since FLTK 1.3.4.
 * It is written to FL/fl_config.h and #included here.
 ******************************************************************************
 * For more informations on FL_ABI_VERSION see README.abi-version.txt.
 ******************************************************************************
 */

#include <FL/fl_config.h>

#  include "Fl_Export.H"
#  include "fl_types.h"
#  include <FL/platform_types.h> // for FL_COMMAND and FL_CONTROL

/** \name Version Numbers

    FLTK defines some constants to help the programmer to
    find out, for which FLTK version a program is compiled.

    The following constants are defined:
 */
/**@{*/

/**
   The major release version of this FLTK library.
   \see FL_VERSION
 */
#define FL_MAJOR_VERSION        1

/**
   The minor release version for this library.

   FLTK remains mostly source-code compatible between minor version changes.
 */
#define FL_MINOR_VERSION        4

/**
   The patch version for this library.

   FLTK remains binary compatible between patches.
 */
#define FL_PATCH_VERSION        0

/**
    The FLTK version number as a \em double.

    FL_VERSION is a \em double that describes the major, minor, and patch
    version numbers.

    Version 1.2.3 is actually stored as 1.0203 to allow for more than 9
    minor and patch releases.

    \deprecated This \p double version number is retained for compatibility
    with existing program code. New code should use \em int FL_API_VERSION
    instead. FL_VERSION is deprecated because comparisons of floating point
    values may fail due to rounding errors. However, there are currently no
    plans to remove this deprecated constant.

    FL_VERSION is equivalent to <em>(double)FL_API_VERSION / 10000</em>.

    \see Fl::version() (deprecated as well)
    \see FL_API_VERSION
    \see Fl::api_version()
 */
#define FL_VERSION      ( (double)FL_MAJOR_VERSION + \
                          (double)FL_MINOR_VERSION * 0.01 + \
                          (double)FL_PATCH_VERSION * 0.0001 )

/**
    The FLTK API version number as an \em int.

    FL_API_VERSION is an \em int that describes the major, minor, and patch
    version numbers.

    Version 1.2.3 is actually stored as 10203 to allow for more than 9
    minor and patch releases.

    The FL_MAJOR_VERSION, FL_MINOR_VERSION, and FL_PATCH_VERSION constants
    give the integral values for the major, minor, and patch releases
    respectively.

    \note FL_API_VERSION is intended to replace the deprecated
    \em double FL_VERSION.

    \see Fl::api_version()
 */
#define FL_API_VERSION (FL_MAJOR_VERSION*10000 + FL_MINOR_VERSION*100 + FL_PATCH_VERSION)

/**
    The FLTK ABI (Application Binary Interface) version number as an \em int.

    FL_ABI_VERSION is an \em int that describes the major, minor, and patch
    ABI version numbers in the same format as FL_API_VERSION.

    The ABI version number \p FL_ABI_VERSION is usually the same as the
    API version \p FL_API_VERSION with the last two digits set to '00'.

    FLTK retains the ABI (Application Binary Interface) during patch
    releases of the same major and minor versions. Examples:

    \verbatim
      FLTK Version  FL_API_VERSION  FL_ABI_VERSION  FL_VERSION (deprecated)
        1.3.0          10300           10300           1.0300
        1.3.4          10304           10300           1.0304
    \endverbatim

    Version 1.2.3 is actually stored as 10203 to allow for more than 9
    minor and patch releases.

    The FL_MAJOR_VERSION, FL_MINOR_VERSION, and FL_PATCH_VERSION constants
    give the integral values for the major, minor, and patch releases
    respectively.

    To enable new ABI-breaking features in patch releases you can configure
    FLTK to use a higher FL_ABI_VERSION.

    \see README.abi-version.txt
 */
#ifndef FL_ABI_VERSION
#define FL_ABI_VERSION (FL_MAJOR_VERSION*10000 + FL_MINOR_VERSION*100)
#endif

/*
  Check if FL_ABI_VERSION is out of allowed range; redefine if necessary.

  This is done to prevent users from defining an illegal ABI version.

  Rule: FL_MAJOR_VERSION * 10000 + FL_MINOR_VERSION * 100
          <= FL_ABI_VERSION <= FL_API_VERSION.

  Example (FLTK 1.3.4):

    10300 <= FL_ABI_VERSION <= 10304

  Note: configure + CMake can be used to define FL_ABI_VERSION, but they
  do not check validity. This is done here.
*/

#if FL_ABI_VERSION < FL_MAJOR_VERSION*10000 + FL_MINOR_VERSION*100

# undef FL_ABI_VERSION
# define FL_ABI_VERSION (FL_MAJOR_VERSION*10000 + FL_MINOR_VERSION*100)

#elif FL_ABI_VERSION > FL_API_VERSION

# undef FL_ABI_VERSION
# define FL_ABI_VERSION FL_API_VERSION

#endif

/**@}*/  // group: Version Numbers

/**
    Every time a user moves the mouse pointer, clicks a button,
    or presses a key, an event is generated and sent to your
    application. Events can also come from other programs like the
    window manager.

    Events are identified by the integer argument passed to the
    Fl_Widget::handle() virtual method. Other information about the
    most recent event is stored in static locations and acquired by
    calling the Fl::event_*() methods. This static information remains
    valid until the next event is read from the window system, so it
    is ok to look at it outside of the handle() method.

    Event numbers can be converted to their actual names using the
    \ref fl_eventnames[] array defined in \#include &lt;FL/names.h&gt;

    \see Fl::event_text(), Fl::event_key(), class Fl::
 */
// DEV NOTE: Keep this list in sync with FL/names.h
enum Fl_Event { // events
  /** No event. */
  FL_NO_EVENT           = 0,

  /** A mouse button has gone down with the mouse pointing at this
      widget. You can find out what button by calling Fl::event_button().
      You find out the mouse position by calling Fl::event_x() and
      Fl::event_y().

      A widget indicates that it "wants" the mouse click by returning non-zero
      from its Fl_Widget::handle() method. It will then become the
      Fl::pushed() widget and will get FL_DRAG and the matching FL_RELEASE events.
      If Fl_Widget::handle() returns zero then FLTK will try sending the FL_PUSH
      to another widget.
   */
  FL_PUSH               = 1,

  /** A mouse button has been released. You can find out what button by
      calling Fl::event_button().

      In order to receive the FL_RELEASE event, the widget must return
      non-zero when handling FL_PUSH.
   */
  FL_RELEASE            = 2,

  /** The mouse has been moved to point at this widget.  This can
      be used for highlighting feedback.  If a widget wants to
      highlight or otherwise track the mouse, it indicates this by
      returning non-zero from its handle() method. It then
      becomes the Fl::belowmouse() widget and will receive
      FL_MOVE and FL_LEAVE events.
   */
  FL_ENTER              = 3,

  /** The mouse has moved out of the widget.
      In order to receive the FL_LEAVE event, the widget must
      return non-zero when handling FL_ENTER.
   */
  FL_LEAVE              = 4,

  /** The mouse has moved with a button held down. The current button state
      is in Fl::event_state(). The mouse position is in Fl::event_x() and
      Fl::event_y().

      In order to receive FL_DRAG events, the widget must return non-zero
      when handling FL_PUSH.
   */
  FL_DRAG               = 5,

  /** This indicates an <I>attempt</I> to give a widget the keyboard focus.

      If a widget wants the focus, it should change itself to display the
      fact that it has the focus, and return non-zero from its handle() method.
      It then becomes the Fl::focus() widget and gets FL_KEYDOWN, FL_KEYUP,
      and FL_UNFOCUS events.

      The focus will change either because the window manager changed which
      window gets the focus, or because the user tried to navigate using tab,
      arrows, or other keys. You can check Fl::event_key() to figure out why
      it moved. For navigation it will be the key pressed and for interaction
      with the window manager it will be zero.
   */
  FL_FOCUS              = 6,

  /** This event is sent to the previous Fl::focus() widget when another
      widget gets the focus or the window loses focus.
   */
  FL_UNFOCUS            = 7,

  /** A key was pressed (FL_KEYDOWN) or released (FL_KEYUP).
      Fl_KEYBOARD is a synonym for FL_KEYDOWN.
      The key can be found in Fl::event_key().
      The text that the key should insert can be found with Fl::event_text()
      and its length is in Fl::event_length(). If you use the key handle()
      should return 1. If you return zero then FLTK assumes you ignored the
      key and will then attempt to send it to a parent widget. If none of
      them want it, it will change the event into a FL_SHORTCUT event.

      To receive FL_KEYBOARD events you must also respond to the FL_FOCUS
      and FL_UNFOCUS events.

      If you are writing a text-editing widget you may also want to call
      the Fl::compose() function to translate individual keystrokes into
      non-ASCII characters.

      FL_KEYUP events are sent to the widget that currently has focus. This
      is not necessarily the same widget that received the corresponding
      FL_KEYDOWN event because focus may have changed between events.
   */
  FL_KEYDOWN            = 8,

  /** Equivalent to FL_KEYDOWN.
      \see FL_KEYDOWN
   */
  FL_KEYBOARD           = 8,

  /** Key release event.
      \see FL_KEYDOWN
   */
  FL_KEYUP              = 9,

  /** The user clicked the close button of a window.
      This event is used internally only to trigger the callback of
      Fl_Window derived classed. The default callback closes the
      window calling Fl_Window::hide().
   */
  FL_CLOSE              = 10,

  /** The mouse has moved without any mouse buttons held down.
      This event is sent to the Fl::belowmouse() widget.

      In order to receive FL_MOVE events, the widget must return
      non-zero when handling FL_ENTER.
   */
  FL_MOVE               = 11,

  /** If the Fl::focus() widget is zero or ignores an FL_KEYBOARD
      event then FLTK tries sending this event to every widget it
      can, until one of them returns non-zero. FL_SHORTCUT is first
      sent to the Fl::belowmouse() widget, then its parents and siblings,
      and eventually to every widget in the window, trying to find an
      object that returns non-zero. FLTK tries really hard to not to ignore
      any keystrokes!

      You can also make "global" shortcuts by using Fl::add_handler(). A
      global shortcut will work no matter what windows are displayed or
      which one has the focus.
   */
  FL_SHORTCUT           = 12,

  /** This widget is no longer active, due to Fl_Widget::deactivate()
      being called on it or one of its parents. Fl_Widget::active() may
      still be true after this, the widget is only active if Fl_Widget::active()
      is true on it and all its parents (use Fl_Widget::active_r() to check this).
   */
  FL_DEACTIVATE         = 13,

  /** This widget is now active, due to Fl_Widget::activate() being
      called on it or one of its parents.
   */
  FL_ACTIVATE           = 14,

  /** This widget is no longer visible, due to Fl_Widget::hide() being
      called on it or one of its parents, or due to a parent window being
      minimized.  Fl_Widget::visible() may still be true after this, but the
      widget is visible only if visible() is true for it and all its
      parents (use Fl_Widget::visible_r() to check this).
   */
  FL_HIDE               = 15,

  /** This widget is visible again, due to Fl_Widget::show() being called on
      it or one of its parents, or due to a parent window being restored.
      Child Fl_Windows respond to this by actually creating the window if not
      done already, so if you subclass a window, be sure to pass FL_SHOW
      to the base class Fl_Widget::handle() method!
   */
  FL_SHOW               = 16,

  /** You should get this event some time after you call Fl::paste().
      The contents of Fl::event_text() is the text to insert and the number
      of characters is in Fl::event_length().
   */
  FL_PASTE              = 17,

  /** The Fl::selection_owner() will get this event before the selection is
      moved to another widget. This indicates that some other widget or program
      has claimed the selection. Motif programs used this to clear the selection
      indication. Most modern programs ignore this.
   */
  FL_SELECTIONCLEAR     = 18,

  /** The user has moved the mouse wheel. The Fl::event_dx() and Fl::event_dy()
      methods can be used to find the amount to scroll horizontally and vertically.
   */
  FL_MOUSEWHEEL         = 19,

  /** The mouse has been moved to point at this widget. A widget that is
      interested in receiving drag'n'drop data must return 1 to receive
      FL_DND_DRAG, FL_DND_LEAVE and FL_DND_RELEASE events.
   */
  FL_DND_ENTER          = 20,

  /** The mouse has been moved inside a widget while dragging data.  A
      widget that is interested in receiving drag'n'drop data should
      indicate the possible drop position.
   */
  FL_DND_DRAG           = 21,

  /** The mouse has moved out of the widget.
   */
  FL_DND_LEAVE          = 22,

  /** The user has released the mouse button dropping data into the widget.
      If the widget returns 1, it will receive the data in the immediately
      following FL_PASTE event.
   */
  FL_DND_RELEASE        = 23,
  /** The screen configuration (number, positions) was changed.
   Use Fl::add_handler() to be notified of this event.
   */
  FL_SCREEN_CONFIGURATION_CHANGED = 24,
  /** The fullscreen state of the window has changed.
   This event is sent to the window's handle method.
   */
  FL_FULLSCREEN         = 25,
  /** The user has made a zoom/pinch/magnification gesture (Mac OS platform only).
      The Fl::event_dy() method can be used to find magnification amount,
      Fl::event_x() and Fl::event_y() are set as well.
      This event is sent to the window's handle method.
     */
  FL_ZOOM_GESTURE       = 26,
  /** A zoom event (ctrl/+/-/0/ or cmd/+/-/0/) was processed.
   Use Fl::add_handler() to be notified of this event.
   */
  FL_ZOOM_EVENT = 27
// DEV NOTE: Keep this list in sync with FL/names.h
};

/** \name When Conditions */
/**@{*/
/** These constants determine when a callback is performed.

    Fl_When is a bit field. Some values are merely shortcuts for common bit
    combinations. New flags may be added in the future, so it's important to
    mask the required bit when reading via \p when().

    \note Some widgets may not fully support \p FL_WHEN_... flags.

    \see Fl_Widget::when(), Fl::callback_reason(), Fl_Callback_Reason, Fl_Widget::do_callback()
 */
enum Fl_When { // Fl_Widget::when():
  FL_WHEN_NEVER             =  0, ///< Never call the callback
  FL_WHEN_CHANGED           =  1, ///< Do the callback only when the widget value changes
  FL_WHEN_NOT_CHANGED       =  2, ///< Do the callback whenever the user interacts with the widget
  FL_WHEN_RELEASE           =  4, ///< Do the callback when the button or key is released and the value changes
  FL_WHEN_RELEASE_ALWAYS    =  6, ///< Do the callback when the button or key is released, even if the value doesn't change
  FL_WHEN_ENTER_KEY         =  8, ///< Do the callback when the user presses the ENTER key and the value changes
  FL_WHEN_ENTER_KEY_ALWAYS  = 10, ///< Do the callback when the user presses the ENTER key, even if the value doesn't change
  FL_WHEN_ENTER_KEY_CHANGED = 11, ///< Do callbacks whether the value changed or not, and when the ENTER key is pressed
  FL_WHEN_CLOSED            = 16  ///< Do the callback when a child of Fl_Tabs is closed
};
/**@}*/          // group: When Conditions


/** \name Callback Reasons */
/**@{*/
/** These constants describe why a callback is performed.

    \see Fl::callback_reason(), Fl_Widget::when(), Fl_When
 */
enum Fl_Callback_Reason {
  FL_REASON_UNKNOWN=0,    ///< unknown or unset reason
  FL_REASON_SELECTED,     ///< an item was selected
  FL_REASON_DESELECTED,   ///< an item was de-selected
  FL_REASON_RESELECTED,   ///< an item was re-selected (double-clicked).
  FL_REASON_OPENED,       ///< an item was opened
  FL_REASON_CLOSED,       ///< an item was closed
  FL_REASON_DRAGGED,      ///< an item was dragged into a new place
  FL_REASON_CANCELLED,    ///< a dialog was cancelled
  FL_REASON_CHANGED,      ///< the value of the widget was modified
  FL_REASON_GOT_FOCUS,    ///< a widget received focus
  FL_REASON_LOST_FOCUS,   ///< a widget lost focus
  FL_REASON_RELEASED,     ///< the mouse button was released
  FL_REASON_ENTER_KEY,    ///< user finished input pressing Enter
  FL_REASON_USER = 32     ///< user defined callback reasons
};
/**@}*/          // group: Callback Reasons


/** \name Names of Non-ASCII keys and mouse buttons

    The following constants define the names of non-ASCII keys on the
    keyboard and of mouse buttons for FL_KEYBOARD and FL_SHORTCUT events.

    \see Fl::event_key() and Fl::get_key(int) (use ASCII letters for all other keys):
 */

/**@{*/

// FIXME: These codes collide with valid Unicode keys

#define FL_Button       0xfee8  ///< A mouse button; use <tt>FL_Button + n</tt> for mouse button \c n.
#define FL_BackSpace    0xff08  ///< The backspace key.
#define FL_Tab          0xff09  ///< The tab key.
#define FL_Iso_Key      0xff0c  ///< The additional key of ISO keyboards.
#define FL_Enter        0xff0d  ///< The enter key.
#define FL_Pause        0xff13  ///< The pause key.
#define FL_Scroll_Lock  0xff14  ///< The scroll lock key.
#define FL_Escape       0xff1b  ///< The escape key.
#define FL_Kana         0xff2e  ///< The Kana key of JIS keyboards.
#define FL_Eisu         0xff2f  ///< The Eisu key of JIS keyboards.
#define FL_Yen          0xff30  ///< The Yen key of JIS keyboards.
#define FL_JIS_Underscore 0xff31 ///< The underscore key of JIS keyboards.
#define FL_Home         0xff50  ///< The home key.
#define FL_Left         0xff51  ///< The left arrow key.
#define FL_Up           0xff52  ///< The up arrow key.
#define FL_Right        0xff53  ///< The right arrow key.
#define FL_Down         0xff54  ///< The down arrow key.
#define FL_Page_Up      0xff55  ///< The page-up key.
#define FL_Page_Down    0xff56  ///< The page-down key.
#define FL_End          0xff57  ///< The end key.
#define FL_Print        0xff61  ///< The print (or print-screen) key.
#define FL_Insert       0xff63  ///< The insert key.
#define FL_Menu         0xff67  ///< The menu key.
#define FL_Help         0xff68  ///< The 'help' key on Mac keyboards
#define FL_Num_Lock     0xff7f  ///< The num lock key.
#define FL_KP           0xff80  ///< One of the keypad numbers; use FL_KP + 'n' for digit n.
#define FL_KP_Enter     0xff8d  ///< The enter key on the keypad, same as Fl_KP+'\\r'.
#define FL_KP_Last      0xffbd  ///< The last keypad key; use to range-check keypad.
#define FL_F            0xffbd  ///< One of the function keys; use FL_F + n for function key n.
#define FL_F_Last       0xffe0  ///< The last function key; use to range-check function keys.
#define FL_Shift_L      0xffe1  ///< The lefthand shift key.
#define FL_Shift_R      0xffe2  ///< The righthand shift key.
#define FL_Control_L    0xffe3  ///< The lefthand control key.
#define FL_Control_R    0xffe4  ///< The righthand control key.
#define FL_Caps_Lock    0xffe5  ///< The caps lock key.
#define FL_Meta_L       0xffe7  ///< The left meta/Windows key.
#define FL_Meta_R       0xffe8  ///< The right meta/Windows key.
#define FL_Alt_L        0xffe9  ///< The left alt key.
#define FL_Alt_R        0xffea  ///< The right alt key.
#define FL_Delete       0xffff  ///< The delete key.
#define FL_Alt_Gr       0xfe03  ///< The AltGr key on some international keyboards.

// These use the Private Use Area (PUA) of the Basic Multilingual Plane
// of Unicode. Guaranteed not to conflict with a proper Unicode character.

// These primarily map to the XFree86 keysym range
#define FL_Volume_Down  0xEF11   ///< Volume control down
#define FL_Volume_Mute  0xEF12   ///< Mute sound from the system
#define FL_Volume_Up    0xEF13   ///< Volume control up
#define FL_Media_Play   0xEF14   ///< Start playing of audio
#define FL_Media_Stop   0xEF15   ///< Stop playing audio
#define FL_Media_Prev   0xEF16   ///< Previous track
#define FL_Media_Next   0xEF17   ///< Next track
#define FL_Home_Page    0xEF18   ///< Display user's home page
#define FL_Mail         0xEF19   ///< Invoke user's mail program
#define FL_Search       0xEF1B   ///< Search
#define FL_Back         0xEF26   ///< Like back on a browser
#define FL_Forward      0xEF27   ///< Like forward on a browser
#define FL_Stop         0xEF28   ///< Stop current operation
#define FL_Refresh      0xEF29   ///< Refresh the page
#define FL_Sleep        0xEF2F   ///< Put system to sleep
#define FL_Favorites    0xEF30   ///< Show favorite locations

/**@}*/  // group: Non-ASCII key names

/** \name Mouse Buttons

    These constants define the button numbers for FL_PUSH and FL_RELEASE events.

    \see Fl::event_button()
*/

/**@{*/

#define FL_LEFT_MOUSE   1       ///< The left mouse button
#define FL_MIDDLE_MOUSE 2       ///< The middle mouse button
#define FL_RIGHT_MOUSE  3       ///< The right mouse button

/**@}*/          // group: Mouse Buttons


/** \name       Event States

        The following constants define bits in the Fl::event_state() value.
*/

/**@{*/          // group: Event States

// FIXME: it would be nice to have the modifiers in the upper 8 bits so that
//        a unicode key (21 bits) can be sent as an unsigned with the modifiers.

#define FL_SHIFT        0x00010000      ///< One of the shift keys is down
#define FL_CAPS_LOCK    0x00020000      ///< The caps lock is on
#define FL_CTRL         0x00040000      ///< One of the ctrl keys is down
#define FL_ALT          0x00080000      ///< One of the alt keys is down
#define FL_NUM_LOCK     0x00100000      ///< The num lock is on
                                        // most X servers do this?
#define FL_META         0x00400000      ///< One of the meta/Windows keys is down
                                        // correct for XFree86
#define FL_SCROLL_LOCK  0x00800000      ///< The scroll lock is on
                                        // correct for XFree86
#define FL_BUTTON1      0x01000000      ///< Mouse button 1 is pushed (L)
#define FL_BUTTON2      0x02000000      ///< Mouse button 2 is pushed (M)
#define FL_BUTTON3      0x04000000      ///< Mouse button 3 is pushed (R)
#define FL_BUTTONS      0x07000000      ///< Any mouse button (1-3) is pushed
#define FL_BUTTON(n)   (0x00800000<<(n)) ///< Mouse button n (n > 0) is pushed

#define FL_KEY_MASK     0x0000ffff      ///< All keys are 16 bit for now
                                        //   FIXME: Unicode needs 21 bits!

/**@}*/          // group: Event States

/** \name Box Types
    \brief FLTK standard box types

    This enum defines the standard box types included with FLTK.

   \note The documented \p enum \p Fl_Boxtype contains some values (names)
      with leading underscores, e.g. \p \b _FL_SHADOW_BOX. This is due to
      technical reasons - please use the same values (names) without the
      leading underscore in your code! Enum values with leading underscores
      are reserved for internal use and subject to change without notice!

    FL_NO_BOX means nothing is drawn at all, so whatever is already
    on the screen remains. The FL_..._FRAME types only draw their edges,
    leaving the interior unchanged. The blue color in the image below
    is the area that is not drawn by the frame types.

    \anchor boxTypesImage
    \image html  boxtypes.png "FLTK Standard Box Types"
    \image latex boxtypes.png "FLTK Standard Box Types" width=12cm

    \note       Not all box types are depicted in the figure above.
                See enum  \ref Fl_Boxtype below for the complete list of box types.
    \see Fl::get_system_colors()
*/

/**@{*/          // group: Box Types

/**
    \brief FLTK standard box types

    This enum defines the standard box types included with FLTK.

   \note The documented \p enum \p Fl_Boxtype contains some values (names)
      with leading underscores, e.g. \p \b _FL_SHADOW_BOX. This is due to
      technical reasons - please use the same values (names) without the
      leading underscore in your code! Enum values with leading underscores
      are reserved for internal use and subject to change without notice!
*/
enum Fl_Boxtype { // boxtypes (if you change these you must also change fl_boxtype.cxx):

  FL_NO_BOX = 0,                ///< nothing is drawn at all, this box is invisible
  FL_FLAT_BOX,                  ///< a flat box
  FL_UP_BOX,                    ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_DOWN_BOX,                  ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_UP_FRAME,                  ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_DOWN_FRAME,                ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_THIN_UP_BOX,               ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_THIN_DOWN_BOX,             ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_THIN_UP_FRAME,             ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_THIN_DOWN_FRAME,           ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_ENGRAVED_BOX,              ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_EMBOSSED_BOX,              ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_ENGRAVED_FRAME,            ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_EMBOSSED_FRAME,            ///< see figure [Standard Box Types](@ref boxTypesImage)
  FL_BORDER_BOX,                ///< see figure [Standard Box Types](@ref boxTypesImage)
  _FL_SHADOW_BOX,               ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_SHADOW_BOX
  FL_BORDER_FRAME,              ///< see figure [Standard Box Types](@ref boxTypesImage)
  _FL_SHADOW_FRAME,             ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_SHADOW_FRAME
  _FL_ROUNDED_BOX,              ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_ROUNDED_BOX
  _FL_RSHADOW_BOX,              ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_RSHADOW_BOX
  _FL_ROUNDED_FRAME,            ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_ROUNDED_FRAME
  _FL_RFLAT_BOX,                ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_RFLAT_BOX
  _FL_ROUND_UP_BOX,             ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_ROUND_UP_BOX
  _FL_ROUND_DOWN_BOX,           ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_ROUND_DOWN_BOX
  _FL_DIAMOND_UP_BOX,           ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_DIAMOND_UP_BOX
  _FL_DIAMOND_DOWN_BOX,         ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_DIAMOND_DOWN_BOX
  _FL_OVAL_BOX,                 ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_OVAL_BOX
  _FL_OSHADOW_BOX,              ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_OSHADOW_BOX
  _FL_OVAL_FRAME,               ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_OVAL_FRAME
  _FL_OFLAT_BOX,                ///< see figure [Standard Box Types](@ref boxTypesImage), use FL_OFLAT_BOX
  _FL_PLASTIC_UP_BOX,           ///< plastic version of FL_UP_BOX, use FL_PLASTIC_UP_BOX
  _FL_PLASTIC_DOWN_BOX,         ///< plastic version of FL_DOWN_BOX, use FL_PLASTIC_DOWN_BOX
  _FL_PLASTIC_UP_FRAME,         ///< plastic version of FL_UP_FRAME, use FL_PLASTIC_UP_FRAME
  _FL_PLASTIC_DOWN_FRAME,       ///< plastic version of FL_DOWN_FRAME, use FL_PLASTIC_DOWN_FRAME
  _FL_PLASTIC_THIN_UP_BOX,      ///< plastic version of FL_THIN_UP_BOX, use FL_PLASTIC_THIN_UP_BOX
  _FL_PLASTIC_THIN_DOWN_BOX,    ///< plastic version of FL_THIN_DOWN_BOX, use FL_PLASTIC_THIN_DOWN_BOX
  _FL_PLASTIC_ROUND_UP_BOX,     ///< plastic version of FL_ROUND_UP_BOX, use FL_PLASTIC_ROUND_UP_BOX
  _FL_PLASTIC_ROUND_DOWN_BOX,   ///< plastic version of FL_ROUND_DOWN_BOX, use FL_PLASTIC_ROUND_DOWN_BOX
  _FL_GTK_UP_BOX,               ///< gtk+ version of FL_UP_BOX, use FL_GTK_UP_BOX
  _FL_GTK_DOWN_BOX,             ///< gtk+ version of FL_DOWN_BOX, use FL_GTK_DOWN_BOX
  _FL_GTK_UP_FRAME,             ///< gtk+ version of FL_UP_FRAME, use FL_GTK_UP_FRAME
  _FL_GTK_DOWN_FRAME,           ///< gtk+ version of FL_DOWN_FRAME, use FL_GTK_DOWN_FRAME
  _FL_GTK_THIN_UP_BOX,          ///< gtk+ version of FL_THIN_UP_BOX, use FL_GTK_THIN_UP_BOX
  _FL_GTK_THIN_DOWN_BOX,        ///< gtk+ version of FL_THIN_DOWN_BOX, use FL_GTK_THIN_DOWN_BOX
  _FL_GTK_THIN_UP_FRAME,        ///< gtk+ version of FL_THIN_UP_FRAME, use FL_GTK_THIN_UP_FRAME
  _FL_GTK_THIN_DOWN_FRAME,      ///< gtk+ version of FL_THIN_DOWN_FRAME, use FL_GTK_THIN_DOWN_FRAME
  _FL_GTK_ROUND_UP_BOX,         ///< gtk+ version of FL_ROUND_UP_BOX, use FL_GTK_ROUND_UP_BOX
  _FL_GTK_ROUND_DOWN_BOX,       ///< gtk+ version of FL_ROUND_DOWN_BOX, use FL_GTK_ROUND_DOWN_BOX
  _FL_GLEAM_UP_BOX,             ///< gleam version of FL_UP_BOX, use FL_GLEAM_UP_BOX
  _FL_GLEAM_DOWN_BOX,           ///< gleam version of FL_DOWN_BOX, use FL_GLEAM_DOWN_BOX
  _FL_GLEAM_UP_FRAME,           ///< gleam version of FL_UP_FRAME, use FL_GLEAM_UP_FRAME
  _FL_GLEAM_DOWN_FRAME,         ///< gleam version of FL_DOWN_FRAME, use FL_GLEAM_DOWN_FRAME
  _FL_GLEAM_THIN_UP_BOX,        ///< gleam version of FL_THIN_UP_BOX, use FL_GLEAM_THIN_UP_BOX
  _FL_GLEAM_THIN_DOWN_BOX,      ///< gleam version of FL_THIN_DOWN_BOX, use FL_GLEAM_THIN_DOWN_BOX
  _FL_GLEAM_ROUND_UP_BOX,       ///< gleam version of FL_ROUND_UP_BOX, use FL_GLEAM_ROUND_UP_BOX
  _FL_GLEAM_ROUND_DOWN_BOX,     ///< gleam version of FL_ROUND_DOWN_BOX, use FL_GLEAM_ROUND_DOWN_BOX
  _FL_OXY_UP_BOX,               ///< oxy version of FL_UP_BOX, use FL_OXY_UP_BOX
  _FL_OXY_DOWN_BOX,             ///< oxy version of FL_DOWN_BOX, use FL_OXY_DOWN_BOX
  _FL_OXY_UP_FRAME,             ///< oxy version of FL_UP_FRAME, use FL_OXY_UP_FRAME
  _FL_OXY_DOWN_FRAME,           ///< oxy version of FL_DOWN_FRAME, use FL_OXY_DOWN_FRAME
  _FL_OXY_THIN_UP_BOX,          ///< oxy version of FL_THIN_UP_BOX, use FL_OXY_THIN_UP_BOX
  _FL_OXY_THIN_DOWN_BOX,        ///< oxy version of FL_THIN_DOWN_BOX, use FL_OXY_THIN_DOWN_BOX
  _FL_OXY_THIN_UP_FRAME,        ///< oxy version of FL_THIN_UP_FRAME, use FL_OXY_THIN_UP_FRAME
  _FL_OXY_THIN_DOWN_FRAME,      ///< oxy version of FL_THIN_DOWN_FRAME, use FL_OXY_THIN_DOWN_FRAME
  _FL_OXY_ROUND_UP_BOX,         ///< oxy version of FL_ROUND_UP_BOX, use FL_OXY_ROUND_UP_BOX
  _FL_OXY_ROUND_DOWN_BOX,       ///< oxy version of FL_ROUND_DOWN_BOX, use FL_OXY_ROUND_DOWN_BOX
  _FL_OXY_BUTTON_UP_BOX,        ///< FL_OXY_BUTTON_UP_BOX (new boxtype ?), use FL_OXY_BUTTON_UP_BOX
  _FL_OXY_BUTTON_DOWN_BOX,      ///< FL_OXY_BUTTON_DOWN_BOX (new boxtype ?), use FL_OXY_BUTTON_DOWN_BOX
  FL_FREE_BOXTYPE,              ///< the first free box type for creation of new box types
  FL_MAX_BOXTYPE = 255          ///< highest legal index for a box type
};

#ifndef FL_DOXYGEN

extern FL_EXPORT Fl_Boxtype fl_define_FL_ROUND_UP_BOX();
#define FL_ROUND_UP_BOX fl_define_FL_ROUND_UP_BOX()
#define FL_ROUND_DOWN_BOX (Fl_Boxtype)(fl_define_FL_ROUND_UP_BOX()+1)
extern FL_EXPORT Fl_Boxtype fl_define_FL_SHADOW_BOX();
#define FL_SHADOW_BOX fl_define_FL_SHADOW_BOX()
#define FL_SHADOW_FRAME (Fl_Boxtype)(fl_define_FL_SHADOW_BOX()+2)
extern FL_EXPORT Fl_Boxtype fl_define_FL_ROUNDED_BOX();
#define FL_ROUNDED_BOX fl_define_FL_ROUNDED_BOX()
#define FL_ROUNDED_FRAME (Fl_Boxtype)(fl_define_FL_ROUNDED_BOX()+2)
extern FL_EXPORT Fl_Boxtype fl_define_FL_RFLAT_BOX();
#define FL_RFLAT_BOX fl_define_FL_RFLAT_BOX()
extern FL_EXPORT Fl_Boxtype fl_define_FL_RSHADOW_BOX();
#define FL_RSHADOW_BOX fl_define_FL_RSHADOW_BOX()
extern FL_EXPORT Fl_Boxtype fl_define_FL_DIAMOND_BOX();
#define FL_DIAMOND_UP_BOX fl_define_FL_DIAMOND_BOX()
#define FL_DIAMOND_DOWN_BOX (Fl_Boxtype)(fl_define_FL_DIAMOND_BOX()+1)
extern FL_EXPORT Fl_Boxtype fl_define_FL_OVAL_BOX();
#define FL_OVAL_BOX fl_define_FL_OVAL_BOX()
#define FL_OSHADOW_BOX (Fl_Boxtype)(fl_define_FL_OVAL_BOX()+1)
#define FL_OVAL_FRAME (Fl_Boxtype)(fl_define_FL_OVAL_BOX()+2)
#define FL_OFLAT_BOX (Fl_Boxtype)(fl_define_FL_OVAL_BOX()+3)

extern FL_EXPORT Fl_Boxtype fl_define_FL_PLASTIC_UP_BOX();
#define FL_PLASTIC_UP_BOX fl_define_FL_PLASTIC_UP_BOX()
#define FL_PLASTIC_DOWN_BOX (Fl_Boxtype)(fl_define_FL_PLASTIC_UP_BOX()+1)
#define FL_PLASTIC_UP_FRAME (Fl_Boxtype)(fl_define_FL_PLASTIC_UP_BOX()+2)
#define FL_PLASTIC_DOWN_FRAME (Fl_Boxtype)(fl_define_FL_PLASTIC_UP_BOX()+3)
#define FL_PLASTIC_THIN_UP_BOX (Fl_Boxtype)(fl_define_FL_PLASTIC_UP_BOX()+4)
#define FL_PLASTIC_THIN_DOWN_BOX (Fl_Boxtype)(fl_define_FL_PLASTIC_UP_BOX()+5)
#define FL_PLASTIC_ROUND_UP_BOX (Fl_Boxtype)(fl_define_FL_PLASTIC_UP_BOX()+6)
#define FL_PLASTIC_ROUND_DOWN_BOX (Fl_Boxtype)(fl_define_FL_PLASTIC_UP_BOX()+7)

extern FL_EXPORT Fl_Boxtype fl_define_FL_GTK_UP_BOX();
#define FL_GTK_UP_BOX fl_define_FL_GTK_UP_BOX()
#define FL_GTK_DOWN_BOX (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+1)
#define FL_GTK_UP_FRAME (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+2)
#define FL_GTK_DOWN_FRAME (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+3)
#define FL_GTK_THIN_UP_BOX (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+4)
#define FL_GTK_THIN_DOWN_BOX (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+5)
#define FL_GTK_THIN_UP_FRAME (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+6)
#define FL_GTK_THIN_DOWN_FRAME (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+7)
#define FL_GTK_ROUND_UP_BOX (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+8)
#define FL_GTK_ROUND_DOWN_BOX (Fl_Boxtype)(fl_define_FL_GTK_UP_BOX()+9)

extern FL_EXPORT Fl_Boxtype fl_define_FL_GLEAM_UP_BOX();
#define FL_GLEAM_UP_BOX fl_define_FL_GLEAM_UP_BOX()
#define FL_GLEAM_DOWN_BOX (Fl_Boxtype)(fl_define_FL_GLEAM_UP_BOX()+1)
#define FL_GLEAM_UP_FRAME (Fl_Boxtype)(fl_define_FL_GLEAM_UP_BOX()+2)
#define FL_GLEAM_DOWN_FRAME (Fl_Boxtype)(fl_define_FL_GLEAM_UP_BOX()+3)
#define FL_GLEAM_THIN_UP_BOX (Fl_Boxtype)(fl_define_FL_GLEAM_UP_BOX()+4)
#define FL_GLEAM_THIN_DOWN_BOX (Fl_Boxtype)(fl_define_FL_GLEAM_UP_BOX()+5)
#define FL_GLEAM_ROUND_UP_BOX (Fl_Boxtype)(fl_define_FL_GLEAM_UP_BOX()+6)
#define FL_GLEAM_ROUND_DOWN_BOX (Fl_Boxtype)(fl_define_FL_GLEAM_UP_BOX()+7)

extern FL_EXPORT Fl_Boxtype fl_define_FL_OXY_UP_BOX();
#define FL_OXY_UP_BOX fl_define_FL_OXY_UP_BOX()
#define FL_OXY_DOWN_BOX (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+1)
#define FL_OXY_UP_FRAME (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+2)
#define FL_OXY_DOWN_FRAME (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+3)
#define FL_OXY_THIN_UP_BOX (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+4)
#define FL_OXY_THIN_DOWN_BOX (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+5)
#define FL_OXY_THIN_UP_FRAME (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+6)
#define FL_OXY_THIN_DOWN_FRAME (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+7)
#define FL_OXY_ROUND_UP_BOX (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+8)
#define FL_OXY_ROUND_DOWN_BOX (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+9)
#define FL_OXY_BUTTON_UP_BOX (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+10)
#define FL_OXY_BUTTON_DOWN_BOX (Fl_Boxtype)(fl_define_FL_OXY_UP_BOX()+11)

#endif // ! FL_DOXYGEN

// conversions of box types to other boxtypes:
/**
  Get the filled version of a frame.
  If no filled version of a given frame exists, the behavior of this function
  is undefined and some random box or frame is returned.
 */
inline Fl_Boxtype fl_box(Fl_Boxtype b) {
  return (Fl_Boxtype)((b<FL_UP_BOX||b%4>1)?b:(b-2));
}
/**
  Get the "pressed" or "down" version of a box.
  If no "down" version of a given box exists, the behavior of this function
  is undefined and some random box or frame is returned.
 */
inline Fl_Boxtype fl_down(Fl_Boxtype b) {
  return (Fl_Boxtype)((b<FL_UP_BOX)?b:(b|1));
}
/**
  Get the unfilled, frame only version of a box.
  If no frame version of a given box exists, the behavior of this function
  is undefined and some random box or frame is returned.
 */
inline Fl_Boxtype fl_frame(Fl_Boxtype b) {
  return (Fl_Boxtype)((b%4<2)?b:(b+2));
}

// back-compatibility box types:
#define FL_FRAME FL_ENGRAVED_FRAME
#define FL_FRAME_BOX FL_ENGRAVED_BOX
#define FL_CIRCLE_BOX FL_ROUND_DOWN_BOX
#define FL_DIAMOND_BOX FL_DIAMOND_DOWN_BOX

/**@}*/  // group: Box Types

/**
   The labeltype() method sets the type of the label.

   \note The documented \p enum \p Fl_Labeltype contains some values (names)
      with leading underscores, e.g. \p \b _FL_IMAGE_LABEL. This is due to
      technical reasons - please use the same values (names) without the
      leading underscore in your code! Enum values with leading underscores
      are reserved for internal use and subject to change without notice!

   The following standard label types are included:
*/
enum Fl_Labeltype {    // labeltypes:
  FL_NORMAL_LABEL = 0, ///< draws the text (0)
  FL_NO_LABEL,         ///< does nothing
  _FL_SHADOW_LABEL,    ///< draws a drop shadow under the text
  _FL_ENGRAVED_LABEL,  ///< draws edges as though the text is engraved
  _FL_EMBOSSED_LABEL,  ///< draws edges as though the text is raised
  _FL_MULTI_LABEL,     ///< draws a composite label \see Fl_Multi_Label
  _FL_ICON_LABEL,      ///< draws the icon associated with the text
  _FL_IMAGE_LABEL,     ///< the label displays an "icon" based on a Fl_Image

  FL_FREE_LABELTYPE    ///< first free labeltype to use for creating own labeltypes
};

/**
  Sets the current label type and returns its corresponding Fl_Labeltype value.
  @{
*/

/** FL_SYMBOL_LABEL is an alias for FL_NORMAL_LABEL.

  '@' symbols can be drawn with normal labels as well.\n
  This definition is for historical reasons only (forms compatibility).
  You should use FL_NORMAL_LABEL instead.
*/
#define FL_SYMBOL_LABEL FL_NORMAL_LABEL
/**
  Initializes the internal table entry for FL_SHADOW_LABEL and returns
  its internal value. Internal use only.
*/
extern Fl_Labeltype FL_EXPORT fl_define_FL_SHADOW_LABEL();
/**
  Draws a label with shadows behind the text.
*/
#define FL_SHADOW_LABEL fl_define_FL_SHADOW_LABEL()

/**
  Initializes the internal table entry for FL_ENGRAVED_LABEL and returns
  its internal value. Internal use only.
*/
extern Fl_Labeltype FL_EXPORT fl_define_FL_ENGRAVED_LABEL();
/**
  Draws a label with engraved text.
*/
#define FL_ENGRAVED_LABEL fl_define_FL_ENGRAVED_LABEL()

/**
  Initializes the internal table entry for FL_EMBOSSED_LABEL and returns
  its internal value. Internal use only.
*/
extern Fl_Labeltype FL_EXPORT fl_define_FL_EMBOSSED_LABEL();
/**
  Draws a label with embossed text.
*/
#define FL_EMBOSSED_LABEL fl_define_FL_EMBOSSED_LABEL()

/**
  Initializes the internal table entry for FL_MULTI_LABEL and returns
  its internal value. Internal use only.
*/
extern Fl_Labeltype FL_EXPORT fl_define_FL_MULTI_LABEL();
/**
  Draws a label that can comprise several parts like text and images.
  \see Fl_Multi_Label
*/
#define FL_MULTI_LABEL fl_define_FL_MULTI_LABEL()

/**
  Initializes the internal table entry for FL_ICON_LABEL and returns
  its internal value. Internal use only.
*/
extern Fl_Labeltype FL_EXPORT fl_define_FL_ICON_LABEL();
/**
  Draws an icon as the label.
*/
#define FL_ICON_LABEL fl_define_FL_ICON_LABEL()

/**
  Initializes the internal table entry for FL_IMAGE_LABEL and returns
  its internal value. Internal use only.
*/
extern Fl_Labeltype FL_EXPORT fl_define_FL_IMAGE_LABEL();
/**
  Draws an image (Fl_Image) as the label.
  This is useful for one particular part of an Fl_Multi_Label.
  Use Fl_Widget::image() and/or Fl_Widget::deimage() for normal widgets
  with images as labels.
*/
#define FL_IMAGE_LABEL fl_define_FL_IMAGE_LABEL()

/** @} */

/** \name Alignment Flags
  Flags to control the label alignment.

  This controls how the label is displayed next to or inside the widget.
  The default value is FL_ALIGN_CENTER (0) for most widgets, which centers
  the label inside the widget.

  All alignment flags use the common prefix "FL_ALIGN_". In the following
  descriptions this prefix is sometimes omitted for brevity.

  Flags can be or'd to achieve a combination of alignments, but there
  are some \e "magic values" (e.g. combinations of TOP and BOTTOM and of
  LEFT and RIGHT) that have special meanings (see below). For instance:\n
  FL_ALIGN_TOP_LEFT == (FL_ALIGN_TOP | FL_ALIGN_LEFT) != FL_ALIGN_LEFT_TOP.

  \code
    Outside alignments (FL_ALIGN_INSIDE is not set):

               TOP_LEFT        TOP       TOP_RIGHT
               +---------------------------------+
       LEFT_TOP|                                 |RIGHT_TOP
               |                                 |
           LEFT|             CENTER              |RIGHT
               |                                 |
    LEFT_BOTTOM|                                 |RIGHT_BOTTOM
               +---------------------------------+
               BOTTOM_LEFT   BOTTOM   BOTTOM_RIGHT

    Inside alignments (FL_ALIGN_INSIDE is set):

               +---------------------------------+
               |TOP_LEFT       TOP      TOP_RIGHT|
               |                                 |
               |LEFT         CENTER         RIGHT|
               |                                 |
               |BOTTOM_LEFT  BOTTOM  BOTTOM_RIGHT|
               +---------------------------------+
  \endcode
  \see Fl_Align, #FL_ALIGN_CENTER, etc.

  \note
    -# Bit positions not defined in the following constants of type
       \p Fl_Align are reserved for future extensions. Do not use.
    -# The \e "magic values" (FL_ALIGN_)LEFT_TOP, RIGHT_TOP, LEFT_BOTTOM,
       and RIGHT_BOTTOM must not be used together with FL_ALIGN_INSIDE.
       Use TOP_LEFT, TOP_RIGHT, BOTTOM_LEFT, or BOTTOM_RIGHT instead.
    -# Although bits can be or'd together there are some unused/illegal
       combinations, for instance:
      - setting both FL_ALIGN_TOP and FL_ALIGN_BOTTOM in combinations other
        than those given in the \p Fl_Align constants below (magic values)
      - setting both FL_ALIGN_LEFT and FL_ALIGN_RIGHT in combinations other
        than those given in the \p Fl_Align constants below (magic values)
      - using one of the "magic values" (2) together with FL_ALIGN_INSIDE
  \note
    Using illegal bit combinations or undefined bits may yield unexpected
    behavior, and this behavior may be changed without notice in future
    FLTK versions.
 */
/**@{*/
/** FLTK type for alignment control. */
typedef unsigned Fl_Align;

  /** Align the label horizontally in the middle. */
const Fl_Align FL_ALIGN_CENTER          = 0x0000;

  /** Align the label at the top of the widget. Inside labels appear below the top,
      outside labels are drawn on top of the widget. */
const Fl_Align FL_ALIGN_TOP             = 0x0001;

  /** Align the label at the bottom of the widget. */
const Fl_Align FL_ALIGN_BOTTOM          = 0x0002;

  /** Align the label at the left of the widget. Inside labels appear left-justified
      starting at the left side of the widget, outside labels are right-justified and
      drawn to the left of the widget. */
const Fl_Align FL_ALIGN_LEFT            = 0x0004;

  /** Align the label to the right of the widget. */
const Fl_Align FL_ALIGN_RIGHT           = 0x0008;

  /** Draw the label inside of the widget. */
const Fl_Align FL_ALIGN_INSIDE          = 0x0010;

  /** If the label contains an image, draw the text on top of the image. */
const Fl_Align FL_ALIGN_TEXT_OVER_IMAGE = 0x0020;

  /** If the label contains an image, draw the text below the image. */
const Fl_Align FL_ALIGN_IMAGE_OVER_TEXT = 0x0000;

  /** All parts of the label that are larger than the widget will not be drawn. */
const Fl_Align FL_ALIGN_CLIP            = 0x0040;

  /** Wrap text that does not fit the width of the widget. */
const Fl_Align FL_ALIGN_WRAP            = 0x0080;

  /** If the label contains an image, draw the text to the right of the image. */
const Fl_Align FL_ALIGN_IMAGE_NEXT_TO_TEXT = 0x0100;

  /** If the label contains an image, draw the text to the left of the image. */
const Fl_Align FL_ALIGN_TEXT_NEXT_TO_IMAGE = 0x0120;

/** If the label contains an image, draw the image or deimage in the background. */
const Fl_Align FL_ALIGN_IMAGE_BACKDROP  = 0x0200;

const Fl_Align FL_ALIGN_TOP_LEFT        = FL_ALIGN_TOP | FL_ALIGN_LEFT;
const Fl_Align FL_ALIGN_TOP_RIGHT       = FL_ALIGN_TOP | FL_ALIGN_RIGHT;
const Fl_Align FL_ALIGN_BOTTOM_LEFT     = FL_ALIGN_BOTTOM | FL_ALIGN_LEFT;
const Fl_Align FL_ALIGN_BOTTOM_RIGHT    = FL_ALIGN_BOTTOM | FL_ALIGN_RIGHT;

/** Outside only, left of widget, top position, magic value: TOP | BOTTOM | LEFT. */
const Fl_Align FL_ALIGN_LEFT_TOP        = 0x0007;

/** Outside only, right of widget, top position, magic value: TOP | BOTTOM | RIGHT. */
const Fl_Align FL_ALIGN_RIGHT_TOP       = 0x000b;

/** Outside only, left of widget, bottom position, magic value: TOP | LEFT | RIGHT. */
const Fl_Align FL_ALIGN_LEFT_BOTTOM     = 0x000d;

/** Outside only, right of widget, bottom position, magic value: BOTTOM | LEFT | RIGHT. */
const Fl_Align FL_ALIGN_RIGHT_BOTTOM    = 0x000e;

/** Nothing, same as FL_ALIGN_CENTER, for back compatibility. */
const Fl_Align FL_ALIGN_NOWRAP          = 0x0000;

/** Mask value to test for TOP, BOTTOM, LEFT, and RIGHT flags. */
const Fl_Align FL_ALIGN_POSITION_MASK   = 0x000f;

/** Mask value to test for image alignment flags. */
const Fl_Align FL_ALIGN_IMAGE_MASK      = 0x0320;
/**@}*/


/** \name Font Numbers
    The following constants define the standard FLTK fonts:
 */
/**@{*/
/** A font number is an index into the internal font table. */
typedef int Fl_Font;

const Fl_Font FL_HELVETICA              = 0;    ///< Helvetica (or Arial) normal (0)
const Fl_Font FL_HELVETICA_BOLD         = 1;    ///< Helvetica (or Arial) bold
const Fl_Font FL_HELVETICA_ITALIC       = 2;    ///< Helvetica (or Arial) oblique
const Fl_Font FL_HELVETICA_BOLD_ITALIC  = 3;    ///< Helvetica (or Arial) bold-oblique
const Fl_Font FL_COURIER                = 4;    ///< Courier normal
const Fl_Font FL_COURIER_BOLD           = 5;    ///< Courier bold
const Fl_Font FL_COURIER_ITALIC         = 6;    ///< Courier italic
const Fl_Font FL_COURIER_BOLD_ITALIC    = 7;    ///< Courier bold-italic
const Fl_Font FL_TIMES                  = 8;    ///< Times roman
const Fl_Font FL_TIMES_BOLD             = 9;    ///< Times roman bold
const Fl_Font FL_TIMES_ITALIC           = 10;   ///< Times roman italic
const Fl_Font FL_TIMES_BOLD_ITALIC      = 11;   ///< Times roman bold-italic
const Fl_Font FL_SYMBOL                 = 12;   ///< Standard symbol font
const Fl_Font FL_SCREEN                 = 13;   ///< Default monospaced screen font
const Fl_Font FL_SCREEN_BOLD            = 14;   ///< Default monospaced bold screen font
const Fl_Font FL_ZAPF_DINGBATS          = 15;   ///< Zapf-dingbats font

const Fl_Font FL_FREE_FONT              = 16;   ///< first one to allocate
const Fl_Font FL_BOLD                   = 1;    ///< add this to Helvetica, Courier, or Times
const Fl_Font FL_ITALIC                 = 2;    ///< add this to Helvetica, Courier, or Times
const Fl_Font FL_BOLD_ITALIC            = 3;    ///< add this to Helvetica, Courier, or Times

/**@}*/

/** Size of a font in pixels.
    This is the approximate height of a font in pixels.
 */
typedef int Fl_Fontsize;

extern FL_EXPORT Fl_Fontsize FL_NORMAL_SIZE;    ///< normal font size

/** \name Colors
    The Fl_Color type holds an FLTK color value.

    Colors are either 8-bit indexes into a <a href="fltk-colormap.png">virtual colormap</a>
    or 24-bit RGB color values. (See \ref drawing_colors for the default FLTK colormap)

    Color indices occupy the lower 8 bits of the value, while
    RGB colors occupy the upper 24 bits, for a byte organization of RGBI.

<pre>
 Fl_Color => 0xrrggbbii
                | | | |
                | | | +--- \ref drawing_colors "index" between 0 and 255
                | | +----- blue color component (8 bit)
                | +------- green component (8 bit)
                +--------- red component (8 bit)
 </pre>

    A color can have either an index or an rgb value. Colors with rgb set
    and an index >0 are reserved for special use.

 */
/**@{*/
/** An FLTK color value; see also \ref drawing_colors  */
typedef unsigned int Fl_Color;

// Standard colors. These are used as default colors in widgets and altered as necessary
const Fl_Color FL_FOREGROUND_COLOR  = 0;        ///< the default foreground color (0) used for labels and text
const Fl_Color FL_BACKGROUND2_COLOR = 7;        ///< the default background color for text, list, and valuator widgets
const Fl_Color FL_INACTIVE_COLOR    = 8;        ///< the inactive foreground color
const Fl_Color FL_SELECTION_COLOR   = 15;       ///< the default selection/highlight color

  // boxtypes generally limit themselves to these colors so
  // the whole ramp is not allocated:

const Fl_Color FL_GRAY0   = 32;                 // 'A'
const Fl_Color FL_DARK3   = 39;                 // 'H'
const Fl_Color FL_DARK2   = 45;                 // 'N'
const Fl_Color FL_DARK1   = 47;                 // 'P'
/** Default background color */
const Fl_Color FL_BACKGROUND_COLOR  = 49;       // 'R' default background color
const Fl_Color FL_LIGHT1  = 50;                 // 'S'
const Fl_Color FL_LIGHT2  = 52;                 // 'U'
const Fl_Color FL_LIGHT3  = 54;                 // 'W'

  // FLTK provides a 5x8x5 color cube that is used with colormap visuals

const Fl_Color FL_BLACK   = 56;
const Fl_Color FL_RED     = 88;
const Fl_Color FL_GREEN   = 63;
const Fl_Color FL_YELLOW  = 95;
const Fl_Color FL_BLUE    = 216;
const Fl_Color FL_MAGENTA = 248;
const Fl_Color FL_CYAN    = 223;
const Fl_Color FL_DARK_RED = 72;

const Fl_Color FL_DARK_GREEN    = 60;
const Fl_Color FL_DARK_YELLOW   = 76;
const Fl_Color FL_DARK_BLUE     = 136;
const Fl_Color FL_DARK_MAGENTA  = 152;
const Fl_Color FL_DARK_CYAN     = 140;

const Fl_Color FL_WHITE         = 255;

/** Colors numbered between FL_FREE_COLOR and FL_FREE_COLOR + FL_NUM_FREE_COLOR - 1
are free for the user to be given any value using Fl::set_color(). */
#define FL_FREE_COLOR     (Fl_Color)16
#define FL_NUM_FREE_COLOR 16
#define FL_GRAY_RAMP      (Fl_Color)32
#define FL_NUM_GRAY       24
#define FL_GRAY           FL_BACKGROUND_COLOR
#define FL_COLOR_CUBE     (Fl_Color)56
#define FL_NUM_RED        5
#define FL_NUM_GREEN      8
#define FL_NUM_BLUE       5

FL_EXPORT Fl_Color fl_inactive(Fl_Color c);

/**
  Type of a custom fl_contrast() function.

  Use this signature to define your own custom fl_contrast() function together
  with fl_contrast_mode(FL_CONTRAST_CUSTOM).
  Example:
  \code
    Fl_Color my_contrast(Fl_Color fg, Fl_Color bg, int context, int size) {
      // calculate contrast and ...
      return color;
    }
    // call this early in your main() program:
    fl_contrast_function(my_contrast);
    fl_contrast_mode(FL_CONTRAST_CUSTOM);
    fl_contrast_level(50); // optional, must be called after fl_contrast_mode()
  \endcode

  For parameters and types see fl_contrast(Fl_Color, Fl_Color, int, int).

  \see fl_contrast(Fl_Color, Fl_Color, int, int)
  \see fl_contrast_mode(int)
*/
typedef Fl_Color (Fl_Contrast_Function)(Fl_Color, Fl_Color, int, int);

FL_EXPORT void fl_contrast_function(Fl_Contrast_Function *f);

/**
  Define the possible modes to calculate fl_contrast().
*/
enum Fl_Contrast_Mode {
  FL_CONTRAST_NONE = 0,     ///< always return foreground color
  FL_CONTRAST_LEGACY,       ///< legacy (FLTK 1.3.x) contrast function
  FL_CONTRAST_CIELAB,       ///< new (FLTK 1.4.0) default function
  FL_CONTRAST_CUSTOM,       ///< optional custom contrast function
  FL_CONTRAST_LAST          ///< internal use only (invalid contrast mode)
};

// The following functions are defined and documented in src/fl_contrast.cxx

FL_EXPORT void fl_contrast_level(int level);
FL_EXPORT int fl_contrast_level();
FL_EXPORT void fl_contrast_mode(int mode);
FL_EXPORT int fl_contrast_mode();

FL_EXPORT Fl_Color fl_contrast(Fl_Color fg, Fl_Color bg, int context = 0, int size = 0);

FL_EXPORT double fl_lightness(Fl_Color color);
FL_EXPORT double fl_luminance(Fl_Color color);

// Other color functions are defined and documented in src/fl_color.cxx

FL_EXPORT Fl_Color fl_color_average(Fl_Color c1, Fl_Color c2, float weight);

/** Returns a lighter version of the specified color. */
inline Fl_Color fl_lighter(Fl_Color c) { return fl_color_average(c, FL_WHITE, .67f); }

/** Returns a darker version of the specified color. */
inline Fl_Color fl_darker(Fl_Color c) { return fl_color_average(c, FL_BLACK, .67f); }

/** Returns the 24-bit color value closest to \p r, \p g, \p b. */
inline Fl_Color fl_rgb_color(uchar r, uchar g, uchar b) {
  if (!r && !g && !b) return FL_BLACK;
  else return (Fl_Color)(((((r << 8) | g) << 8) | b) << 8);
}

/** Returns the 24-bit color value closest to \p g (grayscale). */
inline Fl_Color fl_rgb_color(uchar g) {
  if (!g) return FL_BLACK;
  else return (Fl_Color)(((((g << 8) | g) << 8) | g) << 8);
}

/** Returns a gray color value from black (i == 0) to white (i == FL_NUM_GRAY - 1).
    FL_NUM_GRAY is defined to be 24 in the current FLTK release.
    To get the closest FLTK gray value to an 8-bit grayscale color 'I' use:

 \code
   fl_gray_ramp(I * (FL_NUM_GRAY - 1) / 255)
 \endcode
*/
inline Fl_Color fl_gray_ramp(int i) {return (Fl_Color)(i+FL_GRAY_RAMP);}

/** Returns a color out of the color cube.

  \p r must be in the range 0 to FL_NUM_RED (5) minus 1,
  \p g must be in the range 0 to FL_NUM_GREEN (8) minus 1,
  \p b must be in the range 0 to FL_NUM_BLUE (5) minus 1.

  To get the closest color to a 8-bit set of R,G,B values use:

  \code
    fl_color_cube(R * (FL_NUM_RED - 1) / 255,
       G * (FL_NUM_GREEN - 1) / 255,
       B * (FL_NUM_BLUE - 1) / 255);
  \endcode
 */
inline Fl_Color fl_color_cube(int r, int g, int b) {
  return (Fl_Color)((b*FL_NUM_RED + r) * FL_NUM_GREEN + g + FL_COLOR_CUBE);}

/**@}*/          // group: Colors

/** \name Cursors */
/**@{*/

/** The following constants define the mouse cursors that are available in FLTK.

    Cursors are provided by the system when available, or bitmaps built into
    FLTK as a fallback.
*/
/* FIXME: We should renumber these, but that will break the ABI */
enum Fl_Cursor {
  FL_CURSOR_DEFAULT    =  0, /**< the default cursor, usually an arrow: ↖*/ // U+2196
  FL_CURSOR_ARROW      = 35, /**< an arrow pointer: ↖*/ // U+2196
  FL_CURSOR_CROSS      = 66, /**< crosshair: ＋*/ // U+FF0B
  FL_CURSOR_WAIT       = 76, /**< busy indicator (for instance hourglass): ⌚,⌛*/ // U+231A, U+231B
  FL_CURSOR_INSERT     = 77, /**< I-beam: ⌶*/ // U+2336
  FL_CURSOR_HAND       = 31, /**< pointing hand: ☜*/ // U+261C
  FL_CURSOR_HELP       = 47, /**< question mark pointer:  ?*/
  FL_CURSOR_MOVE       = 27, /**< 4-pointed arrow or hand: ✥, ✋*/ // U+2725, U+270B

  /* Resize indicators */
  FL_CURSOR_NS         = 78, /**< up/down resize: ⇕ */ // U+21D5
  FL_CURSOR_WE         = 79, /**< left/right resize: ⇔*/ // U+21D4
  FL_CURSOR_NWSE       = 80, /**< diagonal resize: ⤡*/ // U+2921
  FL_CURSOR_NESW       = 81, /**< diagonal resize: ⤢*/ // U+2922
  FL_CURSOR_N          = 70, /**< upwards resize: ⤒*/ // U+2912
  FL_CURSOR_NE         = 69, /**< upwards, right resize: ↗*/ // U+2197
  FL_CURSOR_E          = 49, /**< rightwards resize: ⇥*/ // U+21E5
  FL_CURSOR_SE         =  8, /**< downwards, right resize: ⇲*/ // U+21F2
  FL_CURSOR_S          =  9, /**< downwards resize: ⤓*/ // U+2913
  FL_CURSOR_SW         =  7, /**< downwards, left resize: ↙*/ // U+2199
  FL_CURSOR_W          = 36, /**< leftwards resize: ⇤*/ // U+21E4
  FL_CURSOR_NW         = 68, /**< upwards, left resize: ⇱*/ // U+21F1

  FL_CURSOR_NONE       =255  /**< invisible. */
};
/**@}*/          // group: Cursors

/** FD "when" conditions */
enum { // values for "when" passed to Fl::add_fd()
  FL_READ   = 1, /**< Call the callback when there is data to be read. */
  FL_WRITE  = 4, /**< Call the callback when data can be written without blocking. */
  FL_EXCEPT = 8  /**< Call the callback if an exception occurs on the file. */
};

/** visual types and Fl_Gl_Window::mode() (values match Glut) */
enum Fl_Mode {
  FL_RGB        = 0,
  FL_INDEX      = 1,
  FL_SINGLE     = 0,
  FL_DOUBLE     = 2,
  FL_ACCUM      = 4,
  FL_ALPHA      = 8,
  FL_DEPTH      = 16,
  FL_STENCIL    = 32,
  FL_RGB8       = 64,
  FL_MULTISAMPLE= 128,
  FL_STEREO     = 256,
  FL_FAKE_SINGLE = 512, // Fake single buffered windows using double-buffer
  FL_OPENGL3    = 1024
};

// image alpha blending

#define FL_IMAGE_WITH_ALPHA 0x40000000

/** Damage masks */
enum Fl_Damage {
  FL_DAMAGE_CHILD    = 0x01, /**< A child needs to be redrawn. */
  FL_DAMAGE_EXPOSE   = 0x02, /**< The window was exposed. */
  FL_DAMAGE_SCROLL   = 0x04, /**< The Fl_Scroll widget was scrolled. Used by other widgets for other widget specific damages. */
  FL_DAMAGE_OVERLAY  = 0x08, /**< The overlay planes need to be redrawn. */
  FL_DAMAGE_USER1    = 0x10, /**< First user-defined damage bit. */
  FL_DAMAGE_USER2    = 0x20, /**< Second user-defined damage bit. */
  FL_DAMAGE_ALL      = 0x80  /**< Everything needs to be redrawn. */
};

// FLTK 1.0.x compatibility definitions (FLTK_1_0_COMPAT) dropped in 1.4.0

/** Arrow types define the type of arrow drawing function.

  FLTK schemes can draw several graphical elements in their particular way.
  One of these elements is an arrow type that can be in different GUI
  elements like scrollbars, choice buttons, and FLTK's Fl_Return_Button.

  \note This enum is not yet stable (as of FLTK 1.4.0) and may be changed
    without notice as necessary.

  \since 1.4.0
*/

enum Fl_Arrow_Type {
  FL_ARROW_SINGLE = 0x01, ///< Single arrow, e.g. in Fl_Scrollbar
  FL_ARROW_DOUBLE = 0x02, ///< Double arrow, e.g. in Fl_Counter
  FL_ARROW_CHOICE = 0x03, ///< Dropdown box, e.g. in Fl_Choice
  FL_ARROW_RETURN = 0x04  ///< Return arrow, e.g. in Fl_Return_Button
};

/** Fl_Orientation describes the orientation of a GUI element.

  FLTK schemes can draw several graphical elements, for instance arrows,
  pointing at different directions. This enum defines the direction
  to use for drawing a particular GUI element.

  The definition of this enum was chosen such that the enum value can
  be multiplied by 45 to get a rotation angle in degrees starting
  at the horizontal axis (0 = right, 1 = NE, 2 = up, ...) that can be
  used with fl_rotate(). Note: angle is counter-clockwise in degrees.

  The 'unspecified' value \b FL_ORIENT_NONE shall be used for elements
  that would usually not be rotated, like the return arrow of the
  Fl_Return_Button. It can still be used as an angle though since it is
  the same value as \p FL_ORIENT_RIGHT (0 degrees).

  \note This enum is not yet stable (as of FLTK 1.4.0) and may be changed
    without notice as necessary.

  \since 1.4.0
*/

enum Fl_Orientation {
  FL_ORIENT_NONE  = 0x00, ///< GUI element direction is unspecified
  FL_ORIENT_RIGHT = 0x00, ///< GUI element pointing right (  0°)
  FL_ORIENT_NE    = 0x01, ///< GUI element pointing NE    ( 45°)
  FL_ORIENT_UP    = 0x02, ///< GUI element pointing up    ( 90°)
  FL_ORIENT_NW    = 0x03, ///< GUI element pointing NW    (135°)
  FL_ORIENT_LEFT  = 0x04, ///< GUI element pointing left  (180°)
  FL_ORIENT_SW    = 0x05, ///< GUI element pointing SW    (225°)
  FL_ORIENT_DOWN  = 0x06, ///< GUI element pointing down  (270°)
  FL_ORIENT_SE    = 0x07  ///< GUI element pointing SE    (315°)
};

#endif