docs: Add links to some internal layouts that demonstrate various features, and udpate required MSYS64 packages for using lld.

docs/source/initialsetup/compilingmame.rst

@@ -101,8 +101,9 @@ with MSYS2 and the **pacman** package manager.
   ``mingw-w64-i686-python``.
 * For debugging you may want to install ``gdb``.
 * To link using the LLVM linker (generally much faster than the GNU linker),
-  you'll need ``mingw-w64-x86_64-lld`` for 64-bit builds, or
+  you'll need ``mingw-w64-x86_64-lld`` and ``mingw-w64-x86_64-libc++`` for
-  ``mingw-w64-i686-lld`` for 32-bit builds.
+  64-bit builds, or ``mingw-w64-i686-lld`` and ``mingw-w64-i686-libc++`` for
+  32-bit builds.
 * To build against the portable SDL interfaces, you'll need
   ``mingw-w64-x86_64-SDL2`` and ``mingw-w64-x86_64-SDL2_ttf`` for 64-bit builds,
   or ``mingw-w64-i686-SDL2`` and ``mingw-w64-i686-SDL2_ttf`` for 32-bit builds.

docs/source/techspecs/layout_files.rst

@@ -1365,3 +1365,42 @@ To check a layout file for common errors, run the script with the path to the
 file no check and no output file name or base variable name.  For example:
 
     **python scripts/build/complay.py artwork/dino/default.lay**
+
+
+.. _layout-examples:
+
+Example layout files
+--------------------
+
+These layout files demonstrate various artwork system features.  They are all
+internal layouts included in MAME.
+
+`sstrangr.lay <https://git.redump.net/mame/tree/src/mame/layout/sstrangr.lay?h=mame0226>`_
+    A simple case of using translucent colour overlays to visually separate and
+    highlight elements on a black and white screen.
+`seawolf.lay <https://git.redump.net/mame/tree/src/mame/layout/seawolf.lay?h=mame0226>`_
+    This system uses lamps for key gameplay elements.  Blending modes are used
+    for the translucent colour overlay placed over the monitor, and the lamps
+    reflected in front of the monitor.  Also uses collections to allow parts of
+    the layout to be disabled selectively.
+`armora.lay <https://git.redump.net/mame/tree/src/mame/layout/armora.lay?h=mame0226>`_
+    This game’s monitor is viewed directly through a translucent colour overlay
+    rather than being reflected from inside the cabinet.  This means the overlay
+    reflects ambient light as well as affecting the colour of the video image.
+`tranz330.lay <https://git.redump.net/mame/tree/src/mame/layout/tranz330.lay?h=mame0226>`_
+    A multi-segment alphanumeric display and keypad.  The keys are clickable,
+    and provide visual feedback when pressed.
+`esq2by16.lay <https://git.redump.net/mame/tree/src/mame/layout/esq2by16.lay?h=mame0226>`_
+    Builds up a multi-line dot matrix character display.  Repeats are used to
+    avoid repetition for the rows in a character, characters in a line, and
+    lines in a page.  Group colors allow a single element to be used for all
+    four display colours.
+`cgang.lay <https://git.redump.net/mame/tree/src/mame/layout/cgang.lay?h=mame0226>`_
+    Animates the position of element items to simulate an electromechanical
+    shooting gallery game.  Also demonstrates effective use of components to
+    build up complex graphics.
+`unkeinv.lay <https://git.redump.net/mame/tree/src/mame/layout/unkeinv.lay?h=mame0226>`_
+    Shows the position of a slider control with LEDs on it.
+`md6802.lay <https://git.redump.net/mame/tree/src/mame/layout/md6802.lay?h=mame0226>`_
+    Effectively using groups as a procedural programming language to build up an
+    image of a trainer board.