How to do item with more the one fuel category?

[Hideki2D]

I wanna create new furnace, it must use only coal and wood as fuel.
I created new fuel type - "light-fuel", and tried to add it for coal and wood...
But I ran into a problem fuel_category property of item it's a string, and it can't have more than one type of fuel
Do you have some solutions?

[Silari]

Generally you'll want to make those two items in your new category, then add your new category to the buildings that should be able to also burn those things.

[Hideki2D]

If I understand you correctly, I should assign a new group to the items I need, and then go through all the existing entities, find those that use the group that these items were previously in and add a new group to them.
This suits me, then I have a custom furnace that only uses coal and wood, but at the same time other mechanisms that should use it do not break
Code in my data-updates.lua

Code: Select all

local function add_fuel_category_to_entity(entity, new_category)
    local energy = entity.burner or entity.energy_source
    if not energy then return end

    if energy.fuel_category == "chemical" then
        energy.fuel_categories = { "chemical", new_category }
        energy.fuel_category = nil
    elseif energy.fuel_categories then
        local found = false
        for _, cat in pairs(energy.fuel_categories) do
            if cat == new_category then
                found = true
                break
            end
        end
        if not found then
            for _, cat in pairs(energy.fuel_categories) do
                if cat == "chemical" then
                    table.insert(energy.fuel_categories, new_category)
                    break
                end
            end
        end
    end
end

for _, prototypes in pairs(data.raw) do
    for _, entity in pairs(prototypes) do
        add_fuel_category_to_entity(entity, "light-fuel")
    end
end