Subnautica Below Zero map maker

mass_convert_bz.cmd

@echo off

rem ==== start of user settings ====

rem minimum level (0...24)
set LEVEL=16

rem input raw files from AssetStudio (https://github.com/Perfare/AssetStudio)
set MESH_DIR=h:\raw

rem output directories
set OBJ_DIR=h:\obj
set LEVEL_DIR=h:\level

set LUA=lua54_static.exe

rem ==== end of user settings ====

set LUA_DIR=%~dp0%
rem goto :merge

:convert
if not exist "%OBJ_DIR%" mkdir "%OBJ_DIR%"
for /r "%MESH_DIR%" %%i in (*.dat) do (
    "%LUA%" "%LUA_DIR%\mesh2obj_bz.lua" "%%i" "%OBJ_DIR%" %LEVEL%
    if ERRORLEVEL 1 goto eof
)

:merge
if not exist "%LEVEL_DIR%" mkdir "%LEVEL_DIR%"
pushd "%LEVEL_DIR%"
for /l %%i in (%LEVEL% 1 24) do (
    echo merge level %%i
    copy /y "%OBJ_DIR%\*-%%i-*.obj" level-%%i.obj >NUL 2>&1
)
popd

:eof
pause

mesh2obj_bz.lua

local FN = arg[1] or [[h:\sub_raw\unnamed asset-resources.assets-10072.dat]]
local DIR = arg[2] or [[h:\sub_obj]]
local SKIP = tonumber(arg[3]) or 0

print(FN)

if "\\" ~= DIR:sub(-1) then
    DIR = DIR .. "\\"
end

local function writeObj(obj)
    local withNormal = obj.normal[1] and true or false
    local n = withNormal and "_wn" or ""

    local fn = DIR .. obj.name:sub(7) .. n .. ".obj"
    local w = assert(io.open(fn, "w+b"))

    local fmt = {
        head = "#o n_%s\n# %d points, %d faces\n",
        point = "v %f %f %f\n",
        normal = "vn %f %f %f\n",
        group = "g g_%s\ns 1\n",
        face_n = "f -%d//-%d -%d//-%d -%d//-%d\n",
        face = "f -%d -%d -%d\n"
    }

    w:write(fmt.head:format(obj.name, #obj.point, #obj.face))
    for i = 1, #obj.point do
        local p = obj.point[i]
        w:write(fmt.point:format(p[1], p[2], p[3]))
    end

    if withNormal then
        for i = 1, #obj.normal do
            local n = obj.normal[i]
            w:write(fmt.normal:format(n[1], n[2], n[3]))
        end
        w:write(fmt.group:format(obj.name))
        for i = 1, #obj.face do
            local f = obj.face[i]
            w:write(fmt.face_n:format(f[1], f[1], f[2], f[2], f[3], f[3]))
        end
    else
        w:write(fmt.group:format(obj.name))
        for i = 1, #obj.face do
            local f = obj.face[i]
            w:write(fmt.face:format(f[1], f[2], f[3]))
        end
    end

    w:close()
end

local function convert()
    local m = require("mesh_utils_bz")
    local obj
    if SKIP >= 0 then
        local level = m.open(FN) -- get fileSize, name, offset
        if level >= SKIP then
            obj = m.processMesh()
            writeObj(obj)
        end
    else
        m.just_open(FN)
        obj = m.processMesh()
        writeObj(obj)
    end
end

convert()

mesh_utils_bz.lua

local m = {}

local obj = {}

local r
local su = string.unpack

local function uint8()
    local res, _ = su("B", r:read(1))
    return res
end
local function uint16()
    local res, _ = su("H", r:read(2))
    return res
end
local function uint32()
    local res, _ = su("I4", r:read(4))
    return res
end
local function str(len)
    return r:read(len)
end
local function float()
    local res, _ = su("f", r:read(4))
    if res ~= res then res = 0.0 end
    return res
end

local function seek(n) r:seek("cur", n) end

local function padding()
    local pos = r:seek()
    pos = pos % 4
    if pos > 0 then
        seek(4 - pos)
    end
    return r:seek()
end

local function pos() print("!!! pos:" .. r:seek()) end


local function string()
    local sz = uint32()
    local name = str(sz)
    padding()
    return name
end

local function AABB()
    local t = {}
    t.center = {float(), float(), float()}
    t.extent = {float()*2, float()*2, float()*2}
--    print(("center: %s\nextent: %s"):format(
--            table.concat(t.center, ", "), table.concat(t.extent, ", ")))
    return t
end


local function SubMeshes()  -- vector
    local sz = uint32()
    assert(1 == sz, sz)
    seek(4) -- firstByte
    obj.indexCount = uint32()
    seek(4*3)   -- topology, baseVertex, firstVertex
    obj.points = uint32() -- vertexCount
    obj.AABB = AABB()
    
    print(("%s:\t%d points, %d faces"):format(obj.name, obj.points, obj.indexCount//3))
--    print(("center: %s\nextent: %s"):format(
--            table.concat(obj.AABB.center, ", "), table.concat(obj.AABB.extent, ", ")))
end

local function BlendShapeData()
    -- // BlendShapeData Shapes
    assert(0 == uint32())   -- vector vertices
    assert(0 == uint32())   -- vector shape
    assert(0 == uint32())   -- vector channels
    assert(0 == uint32())   -- vector fullWeights
    -- \\ BlendShapeData Shapes
end

local function vars()
    assert(0 == uint32())   -- vector BindPose
    assert(0 == uint32())   -- vector BoneNameHashes
    seek(4*1)               -- unsigned int RootBoneNameHash
    assert(0 == uint32())   -- vector BonesAABB
    assert(0 == uint32())   -- VariableBoneCountWeights VariableBoneCountWeights
    obj.MeshCompression = uint8()       -- UInt8 MeshCompression
    seek(3*1 + 4)         -- bool IsReadable, KeepVertices, KeepIndices, int IndexFormat
end

local function other()
    local localAABB = AABB()
    seek(4) -- MeshUsageFlags
    assert(0 == uint32())   -- vector BakedConvexCollisionMesh
    assert(0 == uint32())   -- vector BakedTriangleCollisionMesh
        seek(4) -- float MeshMetrics[0]
        seek(4) -- float MeshMetrics[1]

    -- StreamingInfo StreamData
    seek(4)     -- unsigned int offset
    seek(4)     -- unsigned int size
    local sz = uint32()
    seek(sz)    -- string path
end



local function bitUnpacker(t)
    local result = {}

    local idx = 1
    local sz = 0
    local buf = 0
    local mask = (1 << t.bitSize) - 1

--    local num = 0
--    while num < t.count do
    for _ = 1, t.count do
        local buf_add
        while sz < t.bitSize do
            buf_add, idx = su("B", t.data, idx)

            buf = (buf_add << sz) + buf
            sz = sz + 8
        end
        local res = buf & mask
        table.insert(result, res)
--        num = num + 1

        buf = buf >> t.bitSize
        sz = sz - t.bitSize
        --print("num", num, "res", res, "buf", buf, "sz", sz)
    end

    return result
end

local function packedBitVector(str, withOpt)
    local t = {}
    local p1 = r:seek()
    t.count = uint32()
    if withOpt then
        t.range = float()
        t.start = float()
    end
    t.sz = uint32()
    t.data = r:read(t.sz)
    padding()
    t.bitSize = uint8()
    local p2 = padding()
--    print(("%12s count:%6d, %10f %10f, sz:%6d, b:%2d, %d-%d"):format(
--        str, t.count, t.range or 0, t.start or 0, t.sz, t.bitSize, p1, p2))
    return t
end

local function processVertices(v)
    local point = {}
    local scale = v.range -- t.start    -- CHECK
    local o = obj.offset
    if v.bitSize == 16 then
        local h, pos = 0, 1
        for i = 1, v.count, 3 do
            local pp = {}
            for j = 1, 3 do
                h, pos = su("H", v.data, pos)
                h = (h * scale / 65535.0) + v.start
                table.insert(pp, h)
            end
            -- fix coord
            pp[1] = o.x + pp[1]
            pp[2] = o.y + pp[2]
            pp[3] = o.z - pp[3]
            table.insert(point, pp)
        end
    else
        assert(false, "not implemented")
    end
    return point
end

local function processNormals(n, s)
    local sign = {}
    local tmp = bitUnpacker(s)
    for i = 1, #tmp do
        sign[i] = tmp[i] == 1 and 1 or -1
    end

    local norm = {}
    tmp = bitUnpacker(n)
    local scale = n.range -- t.start    -- CHECK
    for i = 1, #tmp, 2 do
        local n1 = tmp[i] * scale / 255.0 + n.start
        local n2 = tmp[i+1] * scale / 255.0 + n.start

        local n3s = sign[(i+1)/2]
        local n3 = (1.0 - (n1^2 + n2^2))
        
        n3 = math.abs(n3)^0.5 * n3s
        
        table.insert(norm, {n1, n2, -n3})
    end

    return norm
end

local function processFaces(t)
--    for i = 1, faces do
--        local f1, f2, f3 = points-uint16(), points-uint16(), points-uint16()
--        table.insert(face, { f1, f3, f2 })
--    end
    local face = {}
    local tmp = bitUnpacker(t)
--assert(t.count == #tmp, t.count .. " ~= " .. #tmp)
    local p = obj.points
    
    for i = 1, t.count, 3 do
        local ff = {p - tmp[i], p - tmp[i+2], p - tmp[i+1]}
        table.insert(face, ff)
    end
--assert(t.count // 3 == #f)

    return face
end

local function compressedMesh()
    local t = {}
    assert(0 == uint32())   -- vector IndexBuffer
    -- // VertexData VertexData
    assert(0 == uint32())   -- unsigned int VertexCount
    sz = uint32()           -- vector m_Channels
    seek(sz * 4)            -- ChannelInfo data, 4 * uint8
    assert(0 == uint32())   -- TypelessData DataSize
    -- \\ VertexData VertexData

    -- CompressedMesh CompressedMesh
    local v = packedBitVector("Vertices", true)
    packedBitVector("UV", true)
    local n = packedBitVector("Normals", true, true)
    packedBitVector("Tangents", true)
    packedBitVector("Weights")
    local s = packedBitVector("NormalSigns")
    packedBitVector("TangentSigns")
    packedBitVector("FloatColors")
    packedBitVector("BoneIndices")
    seek(8)     -- ???
    local f = packedBitVector("Triangles")
    seek(4*1)   -- unsigned int UVInfo

    obj.point = processVertices(v)
    obj.normal = {} --processNormals(n, s)
    obj.face = processFaces(f)
end

local function uncompressedMesh()
    obj.face = {}
    local p = obj.points
    -- // vector IndexBuffer
    local sz = uint32()
    for i = 1, sz // 6 do
        local f1, f2, f3 = p-uint16(), p-uint16(), p-uint16()
        table.insert(obj.face, { f1, f3, f2 })
    end
    -- \\ vector IndexBuffer

    -- // VertexData VertexData
    sz = uint32()
--    assert(points == sz)

    sz = uint32()   -- vector m_Channels
    seek(sz * 4)    -- ChannelInfo data, 4 * uint8

    sz = uint32()
--    assert(points == sz // 24)

    obj.point = {}
    obj.normal = {}
    local o = obj.offset
    for _ = 1, obj.points do
        local x, y, z = float() + o.x, float() + o.y, o.z - float()
        table.insert(obj.point, { x, y, z })

--        table.insert(obj.normal, { float(), float(), -float() })
        seek(4*3)
    end
    -- \\ VertexData VertexData

    -- CompressedMesh CompressedMesh
    packedBitVector("Vertices", true)
    packedBitVector("UV", true)
    packedBitVector("Normals", true)
    packedBitVector("Tangents", true)
    packedBitVector("Weights")
    packedBitVector("NormalSigns")
    packedBitVector("TangentSigns")
    packedBitVector("FloatColors")
    packedBitVector("BoneIndices")
    seek(8)     -- ???
    packedBitVector("Triangles")
    seek(4*1)   -- unsigned int UVInfo
end

function m.open(fn)
    r = assert(io.open(fn, "rb"))
    obj.fileSize = r:seek("end")
    r:seek("set")
    obj.name = string()
    for x, y, z in obj.name:gmatch("-(.+)-(.+)-(.+)") do
        obj.offset = {x = x * 32.0, y = y * 32.0, z = z * -32.0}
    end
    
    return obj.offset.y // 32
end

function m.just_open(fn)
    r = assert(io.open(fn, "rb"))
    obj.fileSize = r:seek("end")
    r:seek("set")
    obj.name = string()
    obj.offset = {x = 0.0, y = 0.0, z = 0.0}
end

function m.processMesh()
    SubMeshes()
    BlendShapeData()
    vars()
    if     0 == obj.MeshCompression then uncompressedMesh()
    elseif 2 == obj.MeshCompression then compressedMesh()
    else assert(false, obj.MeshCompression)
    end
    other()
    
    local pos = r:seek()
    assert(obj.fileSize == pos, obj.fileSize .. " ~= " .. pos)

    return obj
end

return m

static Lua executable: https://mega.nz/file/39hykALT#boTEEu_UhGl51HSZcGK-P66XdaadKGmUuQ78TZ-KWx4