respectively. Each palette has 64 color entries, which can be set to any
    RGB value. The palette entry number 0 is used as the background color
    (in the "white" palette this entry cannot be modified, since this palette
    will also be used for printing, where the background is always white).
  - The color palettes can be modified either through the dialog under
    "Options/Set.../Colors" or by using the command

    SET PALETTE <index> <rgb>

    where <index> is a number in the range 0..63 and <rgb> is a hexadecimal
    RGB value, like 0xFFFF00 (which would result in a bright yellow). Note
    that the RGB value must begin with "0x", otherwise it would be taken as a
    decimal number. You can use

    SET PALETTE BLACK|WHITE|COLORED

    to switch to the black, white or colored background palette, respectively.
    Note that there will be no automatic window refresh after this command, so
    you should do a WINDOW; command after this.
  - By default only the palette entries 0..15 are used and they contain the
    same colors as previous versions.
  - The palette entries are grouped into "normal" and "highlight" colors. There
    are always 8 "normal" colors, followed by the corresponding 8 "highlight"
    colors. So colors 0..7 are "normal" colors, 8..15 are their "highlight"
    values, 16..23 are another 8 "normal" colors with 24..31 being their
    "highlight" values and so on. The "highlight" colors are used to visualize
    objects, for instance in the SHOW command.
  - The background color for layout and schematic can now be set to any color.
    Note, though, that in case the background color is neither pure black nor
    pure white, the drawing will be displayed layer by layer, which usually
    makes a window refresh slower than with black or white background.
  - Changes to the "Options/Set..." dialog:
    + The "Grid" Tab has been renamed to "Colors".
    + The minimum visible grid size parameter has been moved to the "Misc" tab.
  - The new User Language builtin function 'palette()' can be used to determine
    the currently used palette as well as the palette entries (see "Help/User
    Language/Builtins/Builtin Functions/Miscellaneous Functions/palette()").

* Control Panel:

  - The tree view in the Control Panel can now be sorted by 'name' or by
    'type' via the pulldown menu option "View/Sort".
  - The Control Panel's pulldown menu option "File/Refresh tree" has been
    moved to "View/Refresh".
  - Directory entries in the Control Panel's tree view which can contain
    libraries now all have the "Use all" and "Use none" options in their
    context menus.
  - New context menu options for libraries, device sets and packages as well
    as Drag&Drop features for copying and updating library objects, and for
    creating new package variants.
  - Drag&Drop of a board, schematic or library file into the appropriate
    editor window now loads the file into that window for editing. The
    previous functionality of performing a library update when dropping a
    library into any editor window has been removed.

* Design Rules:

  - The new Design Rule parameters Shapes/Elongation can be used to define
    the elongation of Long and Offset shaped Pads. Valid values are from 0 to
    200, where 0 results in a regular octagon shape (no elongation) and 100
    gives you a side ratio of 2:1 (100% elongation), which is the ratio that
    has been hard-coded in previous program versions.
  - The Design Rules dialog now has a new tab named "Layers", which defines
    the layer setup for multilayer boards (see "Help/Design Checks/Design Rules").
  - The Design Rules tab "Shapes" contains a new combo box named "First", which
    defines the shape of the "first" pad within a package.
  - The Design Rules tab "Sizes" contains the two new parameters "Min. Micro Via"
    and "Min. Blind Via Ratio".
  - The Design Rules tab "Restring" contains a new set of restring parameters
    for micro vias.

* User Language:

  - The User Language member functions UL_PAD.shape and UL_VIA.shape now return
    PAD_SHAPE_ANNULUS, PAD_SHAPE_THERMAL, VIA_SHAPE_ANNULUS and
    VIA_SHAPE_THERMAL, respectively, if their shape is requested for a supply
    layer (see Help/User Language/Object Types/UL_PAD and UL_VIA).
  - The User Language dialog object dlgListView now accepts a new parameter
    that defines the column and direction to use for sorting.
  - The User Language functions strchr(), strstr(), strrchr() and strrstr()
    now accept an 'index' parameter to start the search at a given position.
  - Opening the same file concurrently in two output() statements in a User
    Language Program is now treated as an error.
  - The User Language objects UL_HOLE, UL_PAD and UL_VIA now have a new
    data member 'drillsymbol'.
  - A User Language Program can now be aborted even if it is currently
    executing a lengthy 'for' or 'while' loop.
  - The new ULP function status() can be used to display a message in the
    editor window's status bar.
  - The User Language dialog function dlgTextView now accepts a second
    parameter to support hyperlinks in Rich Text (see "Help/User
    Language/Dialogs/Dialog objects/dlgTextView()").
  - The User Language dialog function dlgMessageBox can now add an icon
    to the message box by prepending the message string with one of the
    characters '!', ';' or ':' (see "Help/User Language/Dialogs/Predefined
    Dialogs/dlgMessageBox()").
  - Due to the implementation of arbitrary angles and "spin" the following new
    member functions have been added to the User Language:
    UL_PAD.angle, UL_SMD.angle, UL_RECTANGLE.angle, UL_ELEMENT.angle,
    UL_ELEMENT.spin and UL_TEXT.spin.
    Make sure you take these into account in your own ULPs as necessary,
    otherwise boards containing objects with these new features may be handled
    incorrectly. See the 'dxf.ulp' for an example.
  - Due to the modifications of pad shapes, the User Language constants
    PAD_SHAPE_XLONGOCT and PAD_SHAPE_YLONGOCT have been replaced with
    PAD_SHAPE_LONG, and the new constant PAD_SHAPE_OFFSET has been introduced.
  - The new User Language member function UL_PAD.elongation returns the
    elongation value for pads with shapes Long or Offset.
  - The User Language object UL_VIA, now has two new data members 'start' and
    'end', which return the layer numbers in which that via starts and ends.
    The value of 'start' will always be less than that of 'end'. Note that the
    data members 'diameter' and 'shape' will always return the diameter or shape
    that a via would have in the given layer, even if that particular via doesn't
    cover that layer (or if that layer isn't used in the layer setup at all).
  - Due to the implementation of different arc cap styles the member function
    UL_ARC.cap has been added to the User Language.
  - The loop member functions UL_BOARD.arcs(), UL_PACKAGE.arcs(), UL_SHEET.arcs()
    and UL_SYMBOL.arcs() no longer exist, since arcs are now treated a lot like
    wires. Any ULPs that used to loop through arcs must now check the new data
    member UL_WIRE.arc when looping through the wires (see "Help/User
    Language/Object Types/UL_WIRE").
    To convert an existing ULP that uses the arcs() loop member functions
    consider the following example:

    Assume you have a ULP that looks like this:

    void ProcessArc(UL_ARC A) { /* do something with the arc */ }
    void ProcessWire(UL_WIRE W) { /* do something with the wire */ }
    board(B) {
      B.arcs(A) ProcessArc(A);
      B.wires(W) ProcessWire(W);
      }

    To make it run with EAGLE version 4.1 you need to eliminate the 'arcs()'
    call and move the actual arc processing into the ProcessWire() function:

    void ProcessArc(UL_ARC A) { /* do something with the arc */ }
    void ProcessWire(UL_WIRE W)
    {
      if (W.arc)
         ProcessArc(W.arc);
      else
         /* do something with the wire */
    }
    board(B) {
      B.wires(W) ProcessWire(W);
      }

    Note that you only need this explicit handling of arcs if you actually
    need to gain access to parameters only the UL_ARC can provide. If you are
    not interested in that kind of information, you can handle the arcs just
    like ordinary wires, using the parameters the UL_WIRE provides.
  - To be able to handle any UL_ARC on UL_WIRE level the UL_WIRE object now
    has the two additional members 'cap' and 'curve'.
  - The User Language objects UL_PAD, UL_VIA and UL_SMD have a new data member
    'flags', which returns the setting of the flags that control mask and
    thermal generation (see "Help/User Language/Object Types/UL_PAD",
    "Help/User Language/Object Types/UL_VIA" and "Help/User Language/Object
    Types/UL_SMD").
  - The User Language object UL_HOLE has a new data member 'diameter[]' which
    returns the diameter of the solder stop masks.
  - The output() statement in a User Language Program now supports the new
    mode character 'D', which causes the file to be automatically deleted at
    the end of the EAGLE session (see "Help/User Language/Builtins/Builtin
    Statements/output()").
  - The User Language object UL_GRID now has an additional data member named
    'unitdist', which returns the grid unit that was used to define the actual
    grid distance (see "Help/User Language/Object Types/UL_GRID).

* Autorouter:

  - The Autorouter no longer attempts to route within the borders of the
    signal's surrounding rectangle first, because that way it sometimes was
    forced to take an "expensive" path, which it would have avoided if it
    had been allowed to use the entire board area in the first place. This
    may cause longer routing times in some cases, but may just as well speed
    up the routing, especially on complex boards.

* CAM Processor:

  - The new parameter MaxApertureSize can be used in the 'eagle.def' file to
    define an upper limit for the size of the generated apertures for the
    GERBERAUTO and GERBER_RS274X devices. If objects larger than this limit
    are to be displayed, apertures will be emulated for them.
  - If the board contains blind or buried vias, the CAM Processor generates a
    separate drill file for each via length that is actually used in the board.
    The file names are built by adding the number of the start and end layer
    to the base file name, as in

    boardname.drd.0104

    which would be the drill file for the layer stack 1-4. If you want to have
    the layer numbers at a different position, you can use the placeholder %L,
    as in

    .%L.drd

    which would result in

    boardname.0104.drd

    The drill info file name is always generated without layer numbers, and
    any '.' before the %L will be dropped.
    Any previously existing files that would match the given drill file name
    pattern, but would not result from the current job, will be deleted before
    generating any new files. There will be one drill info file per job, which
    contains (amoung other information) a list of all generated drill data files.
  - The aperture wheel file is now checked for duplicate D-codes (see
    "Help/Generating Output/CAM Processor/Output Device/Device
    Parameters/Aperture Wheel File").

* Text editor:

  - Setting the font in a text editor window is now done via the pulldown
    menu option "File/Font..." and no longer via the printer setup. The
    selected font is now also used in the text editor window.

* ADD command:

  - The ADD command now mirrors the object that is attached to the cursor
    when the center mouse button is pressed.

* ARC command:

  - Arcs are now part of a signal if drawn in a signal layer of a board.
    When updating an existing board drawing, arcs in signal layers are
    transferred into signals (either newly generated ones or the ones that
    the arcs are apparently connected to by sharing the same end points).
  - The ARC command now accepts a signal name (just like the WIRE command).
  - The endings of arcs can now be either round or flat (the ARC command
    therefore accepts the new parameters ROUND and FLAT).
    When updating an existing drawing, the 'cap' parameter of all arcs in
    boards, packages and symbols, that have their endings covered by other
    objects (like wires or vias) will be set to 'round'. This allows them
    to be drawn more easily on the various output devices.

* BUS command:

  - The BUS command now has an extended syntax to allow drawing arcs (see
    "Help/Editor Commands/BUS").

* CHANGE command:

  - When changing the layer of a signal wire, only the minimum necessary
    via will be set (according to the layer setup in the Design Rules). It may
    happen that an already existing via of the same signal is extended
    accordingly, or that existing vias are combined to form a longer via if
    that's necessary to allow the desired layer change.
  - The CHANGE command has a new option named VIA, which can be used to change
    the layers a via covers. The syntax is

    CHANGE VIA from-to *

    where 'from' and 'to' are the layer numbers the via shall cover. If that
    exact via is not available in the layer setup of the Design Rules, the
    next longer via will be used (or an error message will be issued in case
    no such via can be set).
  - The CHANGE command can now change the cap style of arcs by using