Add paramtype2s for 4 horizontal rotations and 64 colors (#11431)

4dir is like facedir, but only for 4 horizontal directions: NESW. It is identical in behavior to facedir otherwise. The reason why game makers would want to use this over facedir is 1) simplicity and 2) you get 6 free bits.
It can be used for things like chests and furnaces and you don't need or want them to "flip them on the side" (like you could with facedir).

color4dir is like colorfacedir, but you get 64 colors instead of only 8.

doc/lua_api.txt

@@ -758,6 +758,17 @@ appropriate `paramtype2`:
       first (= 0 + 1) pixel will be picked from the palette.
     * `param2 = 35` is 1 * 32 + 3, so the rotation is 3 and the
       second (= 1 + 1) pixel will be picked from the palette.
+* `paramtype2 = "color4dir"` for nodes which use the first
+  six bits of `param2` for palette indexing. The remaining
+  two bits are describing rotation, as in `4dir` paramtype2.
+  Division by 4 yields the palette index (without stretching the
+  palette). These nodes can have 64 different colors, and the
+  palette should contain 64 pixels.
+  Examples:
+    * `param2 = 17` is 4 * 4 + 1, so the rotation is 1 and the
+      fifth (= 4 + 1) pixel will be picked from the palette.
+    * `param2 = 35` is 8 * 4 + 3, so the rotation is 3 and the
+      ninth (= 8 + 1) pixel will be picked from the palette.
 
 To colorize a node on the map, set its `param2` value (according
 to the node's paramtype2).
@@ -1058,18 +1069,36 @@ The function of `param2` is determined by `paramtype2` in node definition.
     * Supported drawtypes: "torchlike", "signlike", "plantlike",
       "plantlike_rooted", "normal", "nodebox", "mesh"
     * The rotation of the node is stored in `param2`
+    * Node is 'mounted'/facing towards one of 6 directions
     * You can make this value by using `minetest.dir_to_wallmounted()`
     * Values range 0 - 5
     * The value denotes at which direction the node is "mounted":
       0 = y+,   1 = y-,   2 = x+,   3 = x-,   4 = z+,   5 = z-
+    * By default, on placement the param2 is automatically set to the
+      appropriate rotation, depending on which side was pointed at
 * `paramtype2 = "facedir"`
     * Supported drawtypes: "normal", "nodebox", "mesh"
-    * The rotation of the node is stored in `param2`. Furnaces and chests are
-      rotated this way. Can be made by using `minetest.dir_to_facedir()`.
+    * The rotation of the node is stored in `param2`.
+    * Node is rotated around face and axis; 24 rotations in total.
+    * Can be made by using `minetest.dir_to_facedir()`.
+    * Chests and furnaces can be rotated that way, and also 'flipped'
     * Values range 0 - 23
     * facedir / 4 = axis direction:
       0 = y+,   1 = z+,   2 = z-,   3 = x+,   4 = x-,   5 = y-
     * facedir modulo 4 = rotation around that axis
+    * By default, on placement the param2 is automatically set to the
+      horizondal direction the player was looking at (values 0-3)
+    * Special case: If the node is a connected nodebox, the nodebox
+      will NOT rotate, only the textures will.
+* `paramtype2 = "4dir"`
+    * Supported drawtypes: "normal", "nodebox", "mesh"
+    * The rotation of the node is stored in `param2`.
+    * Allows node to be rotated horizontally, 4 rotations in total
+    * Can be made by using `minetest.dir_to_fourdir()`.
+    * Chests and furnaces can be rotated that way, but not flipped
+    * Values range 0 - 3
+    * 4dir modulo 4 = rotation
+    * Otherwise, behavior is identical to facedir
 * `paramtype2 = "leveled"`
     * Only valid for "nodebox" with 'type = "leveled"', and "plantlike_rooted".
         * Leveled nodebox:
@@ -1112,6 +1141,10 @@ The function of `param2` is determined by `paramtype2` in node definition.
     * Same as `facedir`, but with colors.
     * The first three bits of `param2` tells which color is picked from the
       palette. The palette should have 8 pixels.
+* `paramtype2 = "color4dir"`
+    * Same as `facedir`, but with colors.
+    * The first six bits of `param2` tells which color is picked from the
+      palette. The palette should have 64 pixels.
 * `paramtype2 = "colorwallmounted"`
     * Same as `wallmounted`, but with colors.
     * The first five bits of `param2` tells which color is picked from the
@@ -5776,6 +5809,12 @@ Item handling
 * `minetest.facedir_to_dir(facedir)`
     * Convert a facedir back into a vector aimed directly out the "back" of a
       node.
+* `minetest.dir_to_fourdir(dir)`
+    * Convert a vector to a 4dir value, used in `param2` for
+      `paramtype2="4dir"`.
+* `minetest.fourdir_to_dir(fourdir)`
+    * Convert a 4dir back into a vector aimed directly out the "back" of a
+      node.
 * `minetest.dir_to_wallmounted(dir)`
     * Convert a vector to a wallmounted value, used for
       `paramtype2="wallmounted"`.
@@ -5788,7 +5827,7 @@ Item handling
     * Convert yaw (angle) to a vector
 * `minetest.is_colored_paramtype(ptype)`
     * Returns a boolean. Returns `true` if the given `paramtype2` contains
-      color information (`color`, `colorwallmounted` or `colorfacedir`).
+      color information (`color`, `colorwallmounted`, `colorfacedir`, etc.).
 * `minetest.strip_param2_color(param2, paramtype2)`
     * Removes everything but the color information from the
       given `param2` value.
@@ -7893,7 +7932,7 @@ Used by `minetest.register_node`, `minetest.register_craftitem`, and
         -- You can set the currently used color as the "palette_index" field of
         -- the item stack metadata.
         -- The palette is always stretched to fit indices between 0 and 255, to
-        -- ensure compatibility with "colorfacedir" and "colorwallmounted" nodes.
+        -- ensure compatibility with "colorfacedir" (and similar) nodes.
 
         color = "#ffffffff",
         -- Color the item is colorized with. The palette overrides this.