[raiguard][2.1.7] Fluid mixing prevention breaks existing fluidboxes from 2.0 mods (Example code provided)

[MeteorSwarm]

Nothing in the documentation or changelog suggests that it's necessary to change fluidbox code to accommodate the new fluid mixing prevention system described in FFF 442. This is why I think the following behavior is a bug. The newest stable version of Muluna for 2.0.X uses fluidbox code in the greenhouse and fluidbox indices in greenhouse recipes identical to the following: This code works in 2.0.X, but in 2.1.7, connecting carbon dioxide pipes to carbon dioxide input results in a "no fluid mixing" warning.

Recipe

Code: Select all

{
        type = "recipe",
        name = "muluna-tree-growth-greenhouse",
        enabled = false,
        categories = {"muluna-greenhouse"},
        icons = dual_icon("muluna-sapling","carbon-dioxide"),
        ingredients = {
            {type = "item",name = "tree-seed", amount=10}, --Reminder: 1 tree seed = 2 wood
            {type = "fluid",name = "carbon-dioxide", amount=10000,fluidbox_index = 1},
            {type = "fluid",name = "water", amount=500,fluidbox_index = 2},
        },
        results = {
            {type = "item",name = "muluna-sapling", amount=10},
            {type = "fluid",name = "oxygen", amount=10000,ignored_by_productivity=10000,fluidbox_index = 1}
        },
        energy_required=5*60,
        subgroup="muluna-forestry",
        max_productivity = 3,
        allow_quality = false,
        auto_recycle=false,
        allow_productivity = true,
        hide_from_signal_gui = false,
        surface_conditions = {
            {
                property = "temperature",
                max = 314
            }
        }
    },

Greenhouse fluidboxes:

Code: Select all

fluid_boxes = {
      {
        volume = 200,
        pipe_covers = pipecoverspictures(),
        pipe_picture = Muluna.pipe_pictures.greenhouse_pipe_pictures(),
        pipe_connections =
        {
          {flow_direction = "input-output", direction = defines.direction.west, position = {-4.0, 3}},
          {flow_direction = "input-output", direction = defines.direction.east, position = {4.0, 3}},
          {flow_direction = "input-output", direction = defines.direction.south, position = {-3.0, 4}},
          {flow_direction = "input-output", direction = defines.direction.north, position = {-3, -4}},
        },
        production_type = "input",
        --filter = "carbon-dioxide"
      },
        {
          volume = 200,
          pipe_covers = pipecoverspictures(),
          pipe_picture = Muluna.pipe_pictures.greenhouse_pipe_pictures(),
          pipe_connections =
          {
            --{flow_direction = "input", direction = defines.direction.west, position = {-5.0, 0}},
            --{flow_direction = "input", direction = defines.direction.east, position = {5.0, 0}},
            --{flow_direction = "input", direction = defines.direction.south, position = {-0.0, 5}},
            {flow_direction = "input", direction = defines.direction.north, position = {-0, -4}},
          },
          production_type = "input",
          --filter = "water"
        },
        
        {
            volume = 200,
            pipe_covers = pipecoverspictures(),
            pipe_picture = Muluna.pipe_pictures.greenhouse_pipe_pictures(),
            --pipe_picture =  require("__space-age__.prototypes.entity.cryogenic-plant-pictures").pipe_picture,
            --always_draw_covers = true, -- fighting against FluidBoxPrototype::always_draw_covers crazy default
            pipe_connections =
            {
              {flow_direction = "input-output", direction = defines.direction.west, position = {-4.0, -3}},
              {flow_direction = "input-output", direction = defines.direction.east, position = {4.0, -3}},
              {flow_direction = "input-output", direction = defines.direction.south, position = {3.0, 4}},
            {flow_direction = "input-output", direction = defines.direction.north, position = {3, -4}},
            },
            production_type = "output",
            --filter = "oxygen"
        },
        {
          volume = 200,
          pipe_covers = pipecoverspictures(),
          pipe_picture = Muluna.pipe_pictures.greenhouse_pipe_pictures(),
          pipe_connections =
          {
            --{flow_direction = "input", direction = defines.direction.west, position = {-5.0, 0}},
            --{flow_direction = "input", direction = defines.direction.east, position = {5.0, 0}},
            --{flow_direction = "input", direction = defines.direction.south, position = {-0.0, 5}},
            {flow_direction = "input", direction = defines.direction.west, position = {-4, 0}},
          },
          production_type = "input",
          --filter = "fluoroketone-cold",
        },
        {
          volume = 200,
          pipe_covers = pipecoverspictures(),
          pipe_picture = Muluna.pipe_pictures.greenhouse_pipe_pictures(),
          pipe_connections =
          {
            --{flow_direction = "input", direction = defines.direction.west, position = {-5.0, 0}},
            --{flow_direction = "input", direction = defines.direction.east, position = {5.0, 0}},
            --{flow_direction = "input", direction = defines.direction.south, position = {-0.0, 5}},
            {flow_direction = "output", direction = defines.direction.east, position = {4, 0}},
          },
          production_type = "output",
          --filter = "fluoroketone-hot",
        },
    },

I don't believe this fluid mixing prevention system was intended to break existing fluidboxes or recipe fluidbox indices.

Muluna repo: https://github.com/nicholasgower/planet ... 6b663729c9

[darkszero]

This also happens with Moshine Start. There's no fluid indices, but there's an assembling machine with a Fluid Energy source and an fluid box, both passthrough.

06-24-2026, 23-24-57.png (927.75 KiB) Viewed 2011 times

Fluid boxes part of the entity

Code: Select all

    energy_source = {
        type = "fluid",
        maximum_temperature = 165,
        scale_fluid_usage = true,
        effectivity = 0.35,
        fluid_box = {
            production_type = "input",
            filter = "steam",
            volume = 50,
            pipe_connections = {
                { flow_direction = "input-output", direction = defines.direction.east, position = { 1, 0 } },
                { flow_direction = "input-output", direction = defines.direction.west, position = { -1, 0 } }
            },
            pipe_picture = assembler2pipepictures,
            pipe_covers = pipecoverspictures(),
        }
    },

    fluid_boxes = {
        {
            production_type = "input",
            pipe_picture = assembler2pipepictures,
            pipe_covers = pipecoverspictures(),
            volume = 1000,
            pipe_connections = {
                { flow_direction = "input-output", direction = defines.direction.north, position = { 0, -1 } },
                { flow_direction = "input-output", direction = defines.direction.south, position = { 0, 1 } },
            },
        },
    },

The rest of the code can be found at https://github.com/henriquegemignani/mo ... hammer.lua

[darkszero]

With the Steam Hammer, removing the fluidboxes does nothing.

06-24-2026, 23-39-42.png (896.84 KiB) Viewed 1989 times

However just removing the filter for steam in the energy source's fluidbox causes the issue to go away

06-24-2026, 23-40-21.png (1004.75 KiB) Viewed 1989 times

So this seems somewhat different from Muluna's issue.

[MeteorSwarm]

"I'm unable to use [Muluna's] vacuum boiler for most recipes, presumably because of how the bidirectional inputs/outputs interact with the changes to the fluid system."

[MeteorSwarm]

From the Foundry Discord server, in reference to Lignumis: "i can't seem to power a steam assembler with steam from a boiler"

06-28-2026, 19-11-09.png (1.43 MiB) Viewed 1649 times

[raiguard]

This also happens with Moshine Start. There's no fluid indices, but there's an assembling machine with a Fluid Energy source and an fluid box, both passthrough.

06-24-2026, 23-24-57.png

Fluid boxes part of the entity

Code: Select all

    energy_source = {
        type = "fluid",
        maximum_temperature = 165,
        scale_fluid_usage = true,
        effectivity = 0.35,
        fluid_box = {
            production_type = "input",
            filter = "steam",
            volume = 50,
            pipe_connections = {
                { flow_direction = "input-output", direction = defines.direction.east, position = { 1, 0 } },
                { flow_direction = "input-output", direction = defines.direction.west, position = { -1, 0 } }
            },
            pipe_picture = assembler2pipepictures,
            pipe_covers = pipecoverspictures(),
        }
    },

    fluid_boxes = {
        {
            production_type = "input",
            pipe_picture = assembler2pipepictures,
            pipe_covers = pipecoverspictures(),
            volume = 1000,
            pipe_connections = {
                { flow_direction = "input-output", direction = defines.direction.north, position = { 0, -1 } },
                { flow_direction = "input-output", direction = defines.direction.south, position = { 0, 1 } },
            },
        },
    },

The rest of the code can be found at https://github.com/henriquegemignani/mo ... hammer.lua

Please attach a save file with this case - I installed moshine start but I don't have that entity.

Edit: resolved on discord - I needed Moshine Start and to select Moshine in the any planet start settings.

[Thremtopod]

Crucible's pressure forge, which uses steam as its energy source, also has this issue. In the attached save, the pump separating the steam turbines from the pressure forges can't be replaced with pipes.