Screwdriver: allow simple wallmounted rotation.

Allows rotating things like signs and torches. Axis rotation
rotates over all 6 faces, face rotation flips upside down to
flat on floor only, and of course in the 4 horizontal directions.

Made the code a bit more modular to account for different rotation
schemes. Should be easier to extend from here on to other needs,
and the functions can be reused by other mods for convenience.

diff --git a/mods/screwdriver/init.lua b/mods/screwdriver/init.lua
index 383d29cd175206f4ad9aedcbc73e55def458744d..696637a021056efb51ff13257fb2f5452da8b193 100644 (file)
--- a/mods/screwdriver/init.lua
+++ b/mods/screwdriver/init.lua
@@ -19,6 +19,31 @@ screwdriver.rotate_simple = function(pos, node, user, mode, new_param2)
        end
 end
 
+screwdriver.rotate = {}
+
+screwdriver.rotate.facedir = function(node, mode)
+       -- Compute param2
+       local rotationPart = node.param2 % 32 -- get first 4 bits
+       local preservePart = node.param2 - rotationPart
+       local axisdir = math.floor(rotationPart / 4)
+       local rotation = rotationPart - axisdir * 4
+       if mode == screwdriver.ROTATE_FACE then
+               rotationPart = axisdir * 4 + nextrange(rotation, 3)
+       elseif mode == screwdriver.ROTATE_AXIS then
+               rotationPart = nextrange(axisdir, 5) * 4
+       end
+
+       return preservePart + rotationPart
+end
+
+local wallmounted_tbl = {
+       [screwdriver.ROTATE_FACE] = {[2] = 5, [3] = 4, [4] = 2, [5] = 3, [1] = 0, [0] = 1},
+       [screwdriver.ROTATE_AXIS] = {[2] = 5, [3] = 4, [4] = 2, [5] = 1, [1] = 0, [0] = 3}
+}
+screwdriver.rotate.wallmounted = function(node, mode)
+       return wallmounted_tbl[mode][node.param2]
+end
+
 -- Handles rotation
 screwdriver.handler = function(itemstack, user, pointed_thing, mode, uses)
        if pointed_thing.type ~= "node" then
@@ -34,23 +59,14 @@ screwdriver.handler = function(itemstack, user, pointed_thing, mode, uses)
 
        local node = minetest.get_node(pos)
        local ndef = minetest.registered_nodes[node.name]
-       -- verify node is facedir (expected to be rotatable)
-       if not ndef or ndef.paramtype2 ~= "facedir" then
+       -- can we rotate this paramtype2?
+       local fn = screwdriver.rotate[ndef.paramtype2]
+       if not fn then
                return
        end
-       -- Compute param2
-       local rotationPart = node.param2 % 32 -- get first 4 bits
-       local preservePart = node.param2 - rotationPart
-       local axisdir = math.floor(rotationPart / 4)
-       local rotation = rotationPart - axisdir * 4
-       if mode == screwdriver.ROTATE_FACE then
-               rotationPart = axisdir * 4 + nextrange(rotation, 3)
-       elseif mode == screwdriver.ROTATE_AXIS then
-               rotationPart = nextrange(axisdir, 5) * 4
-       end
 
-       local new_param2 = preservePart + rotationPart
        local should_rotate = true
+       local new_param2 = fn(node, mode)
 
        -- Node provides a handler, so let the handler decide instead if the node can be rotated
        if ndef and ndef.on_rotate then