Adds coordinates to the chess and checkers holodeck modules (#70866)

## About The Pull Request
This PR aims to add coordinates on both edges of the preset chess and
checkers (sure, why not) templates used in the holodeck feature: top row
and right column on the inner border of the board; the bottom and left,
just outside it.

## Why It's Good For The Game
This ought to help the player take advantage of the algebraic notation
if they wish to. It also adds, like, an itsy bitsy of decor to both
modules (alas, the checkers module still uses mapedited carboard cutouts
which partially cover some of the letters and numbers, but changing them
is outside the scope of this PR).

## Changelog

🆑
add: Added two sets of coordinates to the checkers and chess modules for
the holodeck.
/🆑

_maps/templates/holodeck_spacecheckers.dmm

@@ -12,6 +12,12 @@
 "d" = (
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
+"f" = (
+/obj/effect/turf_decal/board_letter/e{
+	dir = 1
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
 "g" = (
 /obj/item/cardboard_cutout/adaptive{
 	icon_state = "cutout_clown";
@@ -33,6 +39,86 @@
 	icon_state = "cutout_clown";
 	name = "White King"
 	},
+/obj/effect/turf_decal/board_letter/h{
+	dir = 1
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"i" = (
+/obj/item/cardboard_cutout/adaptive{
+	color = "#9999BB";
+	icon_state = "cutout_greytide";
+	name = "Black Pawn"
+	},
+/obj/effect/turf_decal/board_letter/f{
+	dir = 1
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"j" = (
+/obj/effect/turf_decal/board_letter/f{
+	dir = 1
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"k" = (
+/obj/effect/turf_decal/board_number/four{
+	dir = 4
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"n" = (
+/obj/effect/turf_decal/board_number/seven{
+	dir = 4
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
+"p" = (
+/obj/effect/turf_decal/board_letter/c{
+	dir = 1
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"r" = (
+/obj/item/cardboard_cutout/adaptive{
+	icon_state = "cutout_greytide";
+	name = "White Pawn"
+	},
+/obj/effect/turf_decal/board_number/two{
+	dir = 4
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"s" = (
+/obj/effect/turf_decal/board_letter/a{
+	dir = 1
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"t" = (
+/obj/effect/turf_decal/board_letter/b{
+	dir = 1
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"v" = (
+/obj/effect/turf_decal/board_number/two{
+	dir = 4
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"w" = (
+/obj/effect/turf_decal/board_number/seven{
+	dir = 4
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"x" = (
+/obj/effect/turf_decal/board_number/one{
+	dir = 4
+	},
 /turf/open/floor/holofloor/plating,
 /area/template_noop)
 "z" = (
@@ -63,11 +149,79 @@
 	},
 /turf/open/floor/holofloor/plating,
 /area/template_noop)
+"A" = (
+/obj/effect/turf_decal/board_number/three{
+	dir = 4
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
+"B" = (
+/obj/item/cardboard_cutout/adaptive{
+	color = "#9999BB";
+	icon_state = "cutout_greytide";
+	name = "Black Pawn"
+	},
+/obj/effect/turf_decal/board_letter/h{
+	dir = 1
+	},
+/obj/effect/turf_decal/board_number/eight{
+	dir = 4
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"D" = (
+/obj/effect/turf_decal/board_letter/d{
+	dir = 1
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"E" = (
+/obj/effect/turf_decal/board_letter/a{
+	dir = 1
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
+"F" = (
+/obj/effect/turf_decal/board_number/five{
+	dir = 4
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"G" = (
+/obj/effect/turf_decal/board_number/six{
+	dir = 4
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"H" = (
+/obj/effect/turf_decal/board_number/one{
+	dir = 4
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
 "J" = (
 /turf/open/floor/holofloor{
 	icon_state = "white"
 	},
 /area/template_noop)
+"K" = (
+/obj/effect/turf_decal/board_number/three{
+	dir = 4
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"L" = (
+/obj/effect/turf_decal/board_number/four{
+	dir = 4
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
 "M" = (
 /obj/item/cardboard_cutout/adaptive{
 	color = "#9999BB";
@@ -76,22 +230,99 @@
 	},
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
+"N" = (
+/obj/item/cardboard_cutout/adaptive{
+	color = "#9999BB";
+	icon_state = "cutout_greytide";
+	name = "Black Pawn"
+	},
+/obj/effect/turf_decal/board_number/six{
+	dir = 4
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"O" = (
+/obj/effect/turf_decal/board_letter/c{
+	dir = 1
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
+"P" = (
+/obj/effect/turf_decal/board_letter/g{
+	dir = 1
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"T" = (
+/obj/item/cardboard_cutout/adaptive{
+	color = "#9999BB";
+	icon_state = "cutout_greytide";
+	name = "Black Pawn"
+	},
+/obj/effect/turf_decal/board_letter/b{
+	dir = 1
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"V" = (
+/obj/item/cardboard_cutout/adaptive{
+	color = "#9999BB";
+	icon_state = "cutout_greytide";
+	name = "Black Pawn"
+	},
+/obj/effect/turf_decal/board_letter/d{
+	dir = 1
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"W" = (
+/obj/effect/turf_decal/board_letter/g{
+	dir = 1
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
+"X" = (
+/obj/effect/turf_decal/board_number/five{
+	dir = 4
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
+"Y" = (
+/obj/effect/turf_decal/board_number/eight{
+	dir = 4
+	},
+/turf/open/floor/holofloor/plating,
+/area/template_noop)
+"Z" = (
+/obj/effect/turf_decal/board_letter/e{
+	dir = 1
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
 
 (1,1,1) = {"
 a
-a
-a
-a
-a
-a
-a
-a
-a
+Y
+w
+G
+F
+k
+K
+v
+x
 a
 "}
 (2,1,1) = {"
 a
-J
+E
 M
 J
 d
@@ -99,11 +330,11 @@ J
 c
 J
 c
-a
+s
 "}
 (3,1,1) = {"
 a
-M
+T
 J
 M
 J
@@ -111,11 +342,11 @@ d
 J
 c
 J
-a
+t
 "}
 (4,1,1) = {"
 a
-J
+O
 M
 J
 d
@@ -123,11 +354,11 @@ J
 c
 J
 c
-a
+p
 "}
 (5,1,1) = {"
 a
-M
+V
 J
 M
 J
@@ -135,11 +366,11 @@ d
 J
 c
 J
-a
+D
 "}
 (6,1,1) = {"
 a
-J
+Z
 M
 J
 d
@@ -147,11 +378,11 @@ J
 c
 J
 c
-a
+f
 "}
 (7,1,1) = {"
 a
-M
+i
 J
 M
 J
@@ -159,11 +390,11 @@ d
 J
 c
 J
-a
+j
 "}
 (8,1,1) = {"
 a
-J
+W
 M
 J
 d
@@ -171,17 +402,17 @@ J
 c
 J
 c
-a
+P
 "}
 (9,1,1) = {"
 z
-M
-J
-M
-J
-d
-J
-c
-J
+B
+n
+N
+X
+L
+A
+r
+H
 g
 "}

_maps/templates/holodeck_spacechess.dmm

@@ -6,18 +6,98 @@
 /obj/structure/chess/blackbishop,
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
+"c" = (
+/obj/structure/chess/blackpawn,
+/obj/effect/turf_decal/board_number/two{
+	dir = 4
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"e" = (
+/obj/effect/turf_decal/board_number/one{
+	dir = 4
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"f" = (
+/obj/effect/turf_decal/board_number/four{
+	dir = 4
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
 "g" = (
 /obj/structure/chess/whitepawn,
 /turf/open/floor/holofloor{
 	icon_state = "white"
 	},
 /area/template_noop)
+"h" = (
+/obj/effect/turf_decal/board_letter/b{
+	dir = 1
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"i" = (
+/obj/effect/turf_decal/board_number/six{
+	dir = 4
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"j" = (
+/obj/effect/turf_decal/board_number/five{
+	dir = 4
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
+"k" = (
+/obj/structure/chess/whitepawn,
+/obj/effect/turf_decal/board_number/seven{
+	dir = 4
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
+"l" = (
+/obj/effect/turf_decal/board_letter/a{
+	dir = 1
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"m" = (
+/obj/effect/turf_decal/board_number/seven{
+	dir = 4
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"n" = (
+/obj/effect/turf_decal/board_number/three{
+	dir = 4
+	},
+/turf/open/floor/holofloor{
+	icon_state = "white"
+	},
+/area/template_noop)
 "o" = (
 /obj/structure/chess/whitebishop,
+/obj/effect/turf_decal/board_letter/f{
+	dir = 1
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"p" = (
+/obj/effect/turf_decal/board_number/four{
+	dir = 4
+	},
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
 "q" = (
 /obj/structure/chess/blackrook,
+/obj/effect/turf_decal/board_number/one{
+	dir = 4
+	},
 /turf/open/floor/holofloor{
 	icon_state = "white"
 	},
@@ -28,14 +108,41 @@
 /area/template_noop)
 "s" = (
 /obj/structure/chess/whiterook,
+/obj/effect/turf_decal/board_number/eight{
+	dir = 4
+	},
+/obj/effect/turf_decal/board_letter/h{
+	dir = 1
+	},
+/turf/open/floor/holofloor/dark,
+/area/template_noop)
+"t" = (
+/obj/effect/turf_decal/board_number/six{
+	dir = 4
+	},
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
 "u" = (
 /obj/structure/chess/whiteknight,
+/obj/effect/turf_decal/board_letter/g{
+	dir = 1
+	},
 /turf/open/floor/holofloor{
 	icon_state = "white"
 	},
 /area/template_noop)
+"v" = (
+/obj/effect/turf_decal/board_letter/c{
+	dir = 1
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"w" = (
+/obj/effect/turf_decal/board_number/three{
+	dir = 4
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
 "y" = (
 /obj/structure/chess/blackbishop,
 /turf/open/floor/holofloor{
@@ -44,6 +151,9 @@
 /area/template_noop)
 "z" = (
 /obj/structure/chess/whiterook,
+/obj/effect/turf_decal/board_letter/a{
+	dir = 1
+	},
 /turf/open/floor/holofloor{
 	icon_state = "white"
 	},
@@ -54,14 +164,50 @@
 	icon_state = "white"
 	},
 /area/template_noop)
+"B" = (
+/obj/effect/turf_decal/board_letter/g{
+	dir = 1
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"C" = (
+/obj/effect/turf_decal/board_number/five{
+	dir = 4
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"E" = (
+/obj/effect/turf_decal/board_letter/d{
+	dir = 1
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
 "G" = (
 /obj/structure/chess/whiteknight,
+/obj/effect/turf_decal/board_letter/b{
+	dir = 1
+	},
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
 "H" = (
 /obj/structure/chess/whiteking,
+/obj/effect/turf_decal/board_letter/d{
+	dir = 1
+	},
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
+"J" = (
+/obj/effect/turf_decal/board_letter/h{
+	dir = 1
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
+"K" = (
+/obj/effect/turf_decal/board_letter/e{
+	dir = 1
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
 "L" = (
 /obj/structure/chess/blackknight,
 /turf/open/floor/holofloor/dark,
@@ -82,11 +228,26 @@
 	icon_state = "white"
 	},
 /area/template_noop)
+"P" = (
+/obj/effect/turf_decal/board_number/two{
+	dir = 4
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
 "Q" = (
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
+"S" = (
+/obj/effect/turf_decal/board_number/eight{
+	dir = 4
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
 "U" = (
 /obj/structure/chess/whitebishop,
+/obj/effect/turf_decal/board_letter/c{
+	dir = 1
+	},
 /turf/open/floor/holofloor{
 	icon_state = "white"
 	},
@@ -95,6 +256,12 @@
 /obj/structure/chess/blackrook,
 /turf/open/floor/holofloor/dark,
 /area/template_noop)
+"W" = (
+/obj/effect/turf_decal/board_letter/f{
+	dir = 1
+	},
+/turf/open/floor/holofloor/carpet,
+/area/template_noop)
 "X" = (
 /turf/open/floor/holofloor{
 	icon_state = "white"
@@ -106,6 +273,9 @@
 /area/template_noop)
 "Z" = (
 /obj/structure/chess/whitequeen,
+/obj/effect/turf_decal/board_letter/e{
+	dir = 1
+	},
 /turf/open/floor/holofloor{
 	icon_state = "white"
 	},
@@ -113,14 +283,14 @@
 
 (1,1,1) = {"
 a
-a
-a
-a
-a
-a
-a
-a
-a
+S
+m
+i
+C
+f
+w
+P
+e
 a
 "}
 (2,1,1) = {"
@@ -133,7 +303,7 @@ X
 Q
 A
 V
-a
+l
 "}
 (3,1,1) = {"
 a
@@ -145,7 +315,7 @@ Q
 X
 r
 O
-a
+h
 "}
 (4,1,1) = {"
 a
@@ -157,7 +327,7 @@ X
 Q
 A
 b
-a
+v
 "}
 (5,1,1) = {"
 a
@@ -169,7 +339,7 @@ Q
 X
 r
 M
-a
+E
 "}
 (6,1,1) = {"
 a
@@ -181,7 +351,7 @@ X
 Q
 A
 Y
-a
+K
 "}
 (7,1,1) = {"
 a
@@ -193,7 +363,7 @@ Q
 X
 r
 y
-a
+W
 "}
 (8,1,1) = {"
 a
@@ -205,17 +375,17 @@ X
 Q
 A
 L
-a
+B
 "}
 (9,1,1) = {"
 a
 s
-g
-Q
-X
-Q
-X
-r
+k
+t
+j
+p
+n
+c
 q
-a
+J
 "}

code/game/objects/effects/decals/turfdecal/markings.dm

@@ -492,3 +492,53 @@
 
 /obj/effect/turf_decal/siding/wideplating_new/terracotta/end
 	icon_state = "siding_wideplating_new_end"
+
+/// ALPHANUMERIC DECALS (SO FAR ONLY FOR CHESS ALGEBRAIC NOTATION) ///
+
+/obj/effect/turf_decal/board_number/one
+	icon_state = "board_1"
+
+/obj/effect/turf_decal/board_number/two
+	icon_state = "board_2"
+
+/obj/effect/turf_decal/board_number/three
+	icon_state = "board_3"
+
+/obj/effect/turf_decal/board_number/four
+	icon_state = "board_4"
+
+/obj/effect/turf_decal/board_number/five
+	icon_state = "board_5"
+
+/obj/effect/turf_decal/board_number/six
+	icon_state = "board_6"
+
+/obj/effect/turf_decal/board_number/seven
+	icon_state = "board_7"
+
+/obj/effect/turf_decal/board_number/eight
+	icon_state = "board_8"
+
+/obj/effect/turf_decal/board_letter/a
+	icon_state = "board_a"
+
+/obj/effect/turf_decal/board_letter/b
+	icon_state = "board_b"
+
+/obj/effect/turf_decal/board_letter/c
+	icon_state = "board_c"
+
+/obj/effect/turf_decal/board_letter/d
+	icon_state = "board_d"
+
+/obj/effect/turf_decal/board_letter/e
+	icon_state = "board_e"
+
+/obj/effect/turf_decal/board_letter/f
+	icon_state = "board_f"
+
+/obj/effect/turf_decal/board_letter/g
+	icon_state = "board_g"
+
+/obj/effect/turf_decal/board_letter/h
+	icon_state = "board_h"