[Solved] Merge identical nodes in craft recipe

[texmex]

I'm trying to write some code where I grab all craft recipes of all items respectively with. Most things work already, but I can't figure out how to count the occurances of identical items within the same craft recipe and "merge" them, that is combining them into one occurance of the item suffixed by a number equal to the number of occurances in the "old" recipe.

Essentially I want to turn

Code: Select all

	recipe = {
		{"",           "",           ""          },
		{"group:wood", "",           "group:wood"},
		{"group:wood", "group:wood", "group:wood"},
},

↳ into ↴

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	recipe = {{"group:wood 5"}},

Here's what I've written so far:

Spoiler

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function values(t)
  local i = 0
  return function() i = i + 1; return t[i] end
end

local items = minetest.registered_items

for _,a in pairs(items) do
	local recipe = minetest.get_all_craft_recipes(a.name)
	if a.tiles ~= nil and recipe ~= nil then
		for b in values(recipe) do
			for c in values(b.items) do
				--CODE??
			end
			crafting.register_recipe({
				type = "inv",
				output = b.output,
				items = b.items,
				always_known = true,
			})
		end
	end
end

[Hybrid Dog]

You could use a table as hash map to store the counts for each item.
An item in a craft recipe could be e.g. "default:stone 3", so the item name is not necessarily the itemstring, thus I used the ItemStack function to parse the itemstring reliably.
In the end a list is created which contains the items with their count as itemstring, i.e. the "new" recipe.

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local item_counts = {}
for y = 1, #recipe do
	local row = recipe[y]
	for x = 1, #row do
		local item = ItemStack(row[i])
		local itemname = item:get_name()
		if item_counts[itemname] then
			item_counts[itemname] = item_counts[itemname] + item:get_count()
		else
			item_counts[itemname] = item:get_count()
		end
	end
end

local new_recipe,n = {},1
for name, count in pairs(item_counts) do
	new_recipe[n] = name .. " " .. count
	n = n+1
end

[texmex]

That looks very promising, HybridDog. Thank your for this! I’ll try it out soon.

[texmex]

Hmm, I'm trying the code out but the for x = 1, #row do never gets to run with local recipe = minetest.get_all_craft_recipes(a.name):

Spoiler

Code: Select all

function values(t)
  local i = 0
  return function() i = i + 1; return t[i] end
end

local items = minetest.registered_items

for _,a in pairs(items) do
	local recipe = minetest.get_all_craft_recipes(a.name)
	if a.tiles ~= nil and recipe ~= nil then

		local item_counts = {}
		for y = 1, #recipe do
			--print("y runs now")
			local row = recipe[y]
			for x = 1, #row do
				print("x runs now")
				local item = ItemStack(row[i])
				local itemname = item:get_name()
				if item_counts[itemname] then
					item_counts[itemname] = item_counts[itemname] + item:get_count()
				else
					item_counts[itemname] = item:get_count()
				end
			end
		end

		local new_recipe,n = {},1
		for name, count in pairs(item_counts) do
			 new_recipe[n] = name .. " " .. count
			 n = n+1
		end

		for b in values(new_recipe) do
			crafting.register_recipe({
				type = "inv",
				output = b.output,
				items = b.items,
				always_known = true,
			})
		end
	end
end

[12Me21]

minetest.registered_items isn't an array, it uses the item names as keys.

[texmex]

minetest.registered_items isn't an array, it uses the item names as keys.

Yet this works fine:

Spoiler

Code: Select all

function values(t)
  local i = 0
  return function() i = i + 1; return t[i] end
end

local items = minetest.registered_items
--table.sort(items)

for _,a in pairs(items) do
	local recipe = minetest.get_all_craft_recipes(a.name)
	if a.tiles ~= nil and recipe ~= nil then
		for b in values(recipe) do
			for c in values(b.items) do

			end
			crafting.register_recipe({
				type = "inv",
				output = b.output,
				items = b.items,
				always_known = true,
			})
		end
	end
end

(Sorry, I wrote "ipairs" where in reality I use a "pairs" function, and I didn't publish my "values" function.)

[12Me21]

Make sure this is running after all mods have loaded.

EDIT:
the output of minetest.get_all_craft_recipes is: (from lua_api.txt)

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    * recipe entry table:
        * `method`: 'normal' or 'cooking' or 'fuel'
        * `width`: 0-3, 0 means shapeless recipe
        * `items`: indexed [1-9] table with recipe items
        * `output`: string with item name and quantity

The input items aren't split into rows.

Try this:

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local function combine(recipe)
	local item_counts = {}
	for _, itemstring in pairs(recipe.items) do -- must use pairs here because some slots are nil.
		local stack = ItemStack(itemstring)
		local item_name = stack:get_name()
		item_counts[item_name] = (item_counts[item_name] or 0) + stack:get_count()
	end
	return item_counts
end

minetest.register_on_mods_loaded(function()
	for name in pairs(minetest.registered_items) do
		local recipes = minetest.get_all_craft_recipes(name)
		if recipes then
			for _, recipe in ipairs(recipes) do
				print(dump(combine(recipe)))
			end
		end
	end
end)

[texmex]

Wow, I didn't know register_on_mods_loaded even existed. That will be super useful instead of soft depend on every other little mod!

Your function looks super slick, but it returns

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{["group:wood"] = 5,}

and not

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{{"group:wood 5"}},

[12Me21]

Wow, I didn't know register_on_mods_loaded even existed. That will be super useful instead of soft depend on every other little mod!

I think that was added in 5.0, but before that it was common to use minetest.after(0, function).

Your function looks super slick, but it returns

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{
	["default:stick"] = 2,
	["default:brick"] = 4
}

and not

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{{"group:wood 5"}},

Oh, right
just replace `return item_counts` with something like

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	local stacks = {}
	for name, count in pairs(item_counts) do
		table.insert(stacks, name.." "..count)
	end
	return stacks

I'm not sure whether items with metadata are allowed in recipes... That would break this.

[Hybrid Dog]

Sorry, I didn't read the api.
Converting the hashmap to a list should still work, as 12Me21 already showed.
I generally don't use table.insert.

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local new_recipe = {}
for name, count in pairs(item_counts) do
	new_recipe[#new_recipe+1] = name .. " " .. count
end

[texmex]

Thank you both, you've been immensely helpful!

I ended up building on 12Me21's solution and with the (for me) newly discovered register_on_mods_loaded function:

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local function combine(recipe)
	local item_counts = {}
	for _, itemstring in pairs(recipe.items) do -- must use pairs here because some slots are nil.
		local stack = ItemStack(itemstring)
		local item_name = stack:get_name()
		item_counts[item_name] = (item_counts[item_name] or 0) + stack:get_count()
	end
	local stacks = {}
	for name, count in pairs(item_counts) do
		table.insert(stacks, name.." "..count)
	end
	return stacks
end

minetest.register_on_mods_loaded(function()
	for name in spairs(minetest.registered_items) do
		local recipes = minetest.get_all_craft_recipes(name)
		if recipes then
			for _, recipe in ipairs(recipes) do
				if recipe.method == "normal" then
					crafting.register_recipe({
						type = "inv",
						output = recipe.output,
						items = combine(recipe),
						always_known = true,
					})
				end
			end
		end
	end
end)

(spairs is pairs but sorted)

Now I can finally haz grid-less crafting!

[Hybrid Dog]

Did you consider special recipes yet?
* Shapeless recipes are already grid-less I think, so you may want to handle them differently. recipe.width is 0 in this case.
* There're also replacements, where you get more than one itemstack as crafting output, an item in the craft grid is replaced with another one: https://github.com/minetest/minetest/bl ... .txt#L6130
* Mods might register functions which are executed when the player crafts something: https://github.com/minetest/minetest/bl ... .txt#L3669, a mod may for example make the player be teleported somewhere when it crafts something.

[texmex]

Nope, I haven't yet. This is merely to carry over the majority of MTG recipes to the other system in order to build and iterate upon it but not with the goal of having complete feature parity.

[texmex]

* Shapeless recipes are already grid-less I think, so you may want to handle them differently. recipe.width is 0 in this case.

I think they work equally good as the otherones, not seeing why I should treat them differently.

* There're also replacements, where you get more than one itemstack as crafting output, an item in the craft grid is replaced with another one: https://github.com/minetest/minetest/bl ... .txt#L6130

Can you show me a replacement recipe? I haven't found a single one in MTG at least, that's not a cooking recipe. (this code is only supposed to handle normal ones)

* Mods might register functions which are executed when the player crafts something: https://github.com/minetest/minetest/bl ... .txt#L3669, a mod may for example make the player be teleported somewhere when it crafts something.

I think that works already, at least the awards mod is able to detect crafted recipes.

[Hybrid Dog]

Here's a replacement recipe: https://github.com/minetest-mods/moretr ... s.lua#L110

[texmex]

Here's a replacement recipe: https://github.com/minetest-mods/moretr ... s.lua#L110

You're right, the recipe is craftable but the replacements aren't added. Not too interested in tending to since that requires changes to the crafting mod itself, of which I know nothing but the API.