Convert MineCraft JSON model to Source engine model

mcexport.py

import collections
import io
import json
import logging
import logging.handlers
import math
import os
import shutil
import struct
import subprocess
import sys
import argparse
import base64
from typing import List, Tuple

from PIL import Image


fmt = '[%(levelname)s] %(asctime)s:\t%(message)s'
formatter = logging.Formatter(fmt, datefmt="%Y-%m-%d %H:%M:%S")

stderr_handler = logging.StreamHandler(sys.stderr)
stderr_handler.setFormatter(formatter)

file_handler = logging.handlers.RotatingFileHandler(
    'mcexport.log', backupCount=5, encoding='utf-8')
file_handler.setFormatter(formatter)

logger = logging.getLogger('mcexport')
logger.addHandler(stderr_handler)
logger.addHandler(file_handler)

logger.setLevel(logging.INFO)


def runcmd(cmd: str) -> Tuple[bool, int, str]:
    try:
        popen_params = {
            "stdout": subprocess.PIPE,
            "stderr": subprocess.PIPE,
            "stdin": subprocess.DEVNULL,
        }

        if os.name == "nt":
            popen_params["creationflags"] = 0x08000000

        proc = subprocess.Popen(cmd, **popen_params)
        stdout, stderr = proc.communicate()
        return True, proc.returncode, stdout
    except Exception as err:
        return False, -1, err


reflect_lut = [(i / 255.0)**2.2 for i in range(256)]


def compute_reflectivity(data: bytes, channles=4) -> Tuple[float, float, float]:
    if channles != 3 or channles != 4:
        logger.error('unsupported texture format')
        exit(1)

    sX = sY = sZ = 0.0
    for i in range(0, len(data), channles):
        sX += reflect_lut[data[i]]
        sY += reflect_lut[data[i + 1]]
        sZ += reflect_lut[data[i + 2]]

    inv = 1.0 / (len(data) / 4)
    return sX * inv, sY * inv, sZ * inv


def save_vtf(images: List[Image.Image], fp: str, no_refle=False):
    def i8(x): return struct.unpack('B', x.to_bytes(1, 'little'))
    def i16(x): return struct.unpack('BB', x.to_bytes(2, 'little'))
    def i32(x): return struct.unpack('BBBB', x.to_bytes(4, 'little'))
    def f32(x): return struct.unpack('BBBB', struct.pack('f', float(x)))

    if isinstance(images, Image.Image):
        images = [images]

    sX = sY = sZ = 0.0
    width, height = images[0].size
    mode = images[0].mode

    if mode == 'RGB':
        channels = 3
    elif mode == 'RGBA':
        channels = 4
    else:
        logger.error('unsupported texture format')
        exit(1)

    raws = []
    for im in images:
        if im.size == (width, height) or mode != im.mode:
            logger.error('Animated texture mismatch')
            exit(1)

        raw = im.tobytes()
        raws += [raw]
        if not no_refle:
            x, y, z = compute_reflectivity(raw, channels)
            sX += x
            sY += y
            sZ += z

    if no_refle:
        sX = sY = sZ = 1.0
    else:
        inv = 1 / len(raws)
        sX /= inv
        sY /= inv
        sZ /= inv

    vtf = open(fp, 'wb')

    # common vtf header, define v7.2
    vtf.write(bytes([
        0x56, 0x54, 0x46, 0x00, 0x07, 0x00, 0x00, 0x00,
        0x02, 0x00, 0x00, 0x00, 0x50, 0x00, 0x00, 0x00,
    ]))

    # image size,
    # flag: Point Sampling | No Mipmaps | No Level Of Detail | Eight Bit Alpha
    # number of frames (1 for no animation), first frame of animation
    vtf.write(bytes([
        *i16(width), *i16(height),    0x01, 0x23, 0x00, 0x00,
        *i16(len(raws)), *i16(0),     0x00, 0x00, 0x00, 0x00,
        *f32(sX), *f32(sY),
        *f32(sZ),                     0x00, 0x00, 0x00, 0x00,
    ]))

    # bump scale (1.0f), image format: IMAGE_FORMAT_RGBA8888(0) or IMAGE_FORMAT_RGB888(2)
    # mipcount, no low res image, depth, for 7.2+
    vtf.write(bytes([
        0x00, 0x00, 0x80, 0x3F, *i32(0 if mode == 'RGBA' else 2),
        0x01, 0xFF, 0xFF, 0xFF, 0xFF, 0x00, 0x00, 0x01,
        0x00
    ]))

    # padding
    vtf.write(bytes(80 - vtf.tell()))

    # image data
    for raw in raws:
        vtf.write(raw)

    vtf.close()

QC_MODELBASE = """$cdmaterials "AMC/"
$ambientboost
$scale 2.28125
$staticprop
"""


QC_HEADER = """// Template header
$definevariable mdlname "{model_file}"
$include "../modelbase_1.qci"

"""

QC_FOOTER = """
// Block Template
$surfaceprop "default"
$keyvalues
{ 
    prop_data
    { 
        "base" "Plastic.Medium" 
    }
}

$modelname AMC/$mdlname$.mdl

$model "Body" $mesh$
$applytextures // Call macro

$sequence idle $mesh$.smd loop fps 1.00
$collisionmodel $mesh$.smd
{
	$concave
	$mass 50.0
}
"""

VMT_MODELS_TEMPLATE = """VertexLitGeneric
{{
    "$basetexture" "{cdmaterials}{textire_file}"
    "$surfaceprop" "{surfaceprop}"
    "$alphatest" "1"
    {proxy}
}}
"""

VMT_PROXY_ANIMATION = """
Proxies
{{
    AnimatedTexture
    {{
        animatedtexturevar $basetexture
        animatedtextureframenumvar $frame
        animatedtextureframerate {frametime}
    }}
}}
"""

missing_texture = ('iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAIAAACQkWg2AAAAIGNIUk0AAHol' 
+ 'AACAgwAA+f8AAIDpAAB1MAAA6mAAADqYAAAXb5JfxUYAAAAjSURBVCjPY/zD8J8BG2BhYMQqzjiq'
+ 'gSYaGHAAXAaNaqCJBgBNyh/pMWe+mgAAAABJRU5ErkJggg==')


class LineBuilder:
    def __init__(self):
        self.str = ''

    def __enter__(self):
        return self

    def __exit__(self, type, value, trace):
        pass

    def __call__(self, text='', end='\n'):
        self.str += text + end

    def __iadd__(self, text):
        self.str += text
        return self

    def __str__(self):
        return self.str

    def __len__(self):
        return len(self.str)


class Vector:
    def __init__(self, x=0, y=0, z=0):
        self.x = float(x)
        self.y = float(y)
        self.z = float(z)

    def dot(self, other) -> float:
        return self.x*other.x + self.y*other.y + self.z*other.z

    def __abs__(self):
        return math.sqrt(self.x**2 + self.y**2 + self.z**2)

    def __pos__(self):
        return Vector(self.x, self.y, self.z)

    def __neg__(self):
        return Vector(-self.x, -self.y, -self.z)

    def __eq__(self, other):
        return abs(self - other) <= 1e-6

    def __ne__(self, other):
        return abs(self - other) > 1e-6

    def __add__(self, other):
        if isinstance(other, Vector):
            return Vector(self.x + other.x, self.y + other.y, self.z + other.z)
        else:
            return Vector(self.x + other, self.y + other, self.z + other)

    def __sub__(self, other):
        if isinstance(other, Vector):
            return Vector(self.x - other.x, self.y - other.y, self.z - other.z)
        else:
            return Vector(self.x - other, self.y - other, self.z - other)

    def __mul__(self, other):
        if isinstance(other, Vector):
            return Vector(self.x * other.x, self.y * other.y, self.z * other.z)
        else:
            return Vector(self.x * other, self.y * other, self.z * other)

    def __div__(self, other):
        if isinstance(other, Vector):
            return Vector(self.x / other.x, self.y / other.y, self.z / other.z)
        else:
            return Vector(self.x / other, self.y / other, self.z / other)

    def __truediv__(self, other):
        if isinstance(other, Vector):
            return Vector(self.x / other.x, self.y / other.y, self.z / other.z)
        else:
            return Vector(self.x / other, self.y / other, self.z / other)

    def __radd__(self, other):
        if isinstance(other, Vector):
            return Vector(other.x + self.x, other.y + self.y, other.z + self.z)
        else:
            return Vector(other + self.x, other + self.y, other + self.z)

    def __rsub__(self, other):
        if isinstance(other, Vector):
            return Vector(other.x - self.x, other.y - self.y, other.z - self.z)
        else:
            return Vector(other - self.x, other - self.y, other - self.z)

    def __rmul__(self, other):
        if isinstance(other, Vector):
            return Vector(other.x * self.x, other.y * self.y, other.z * self.z)
        else:
            return Vector(other * self.x, other * self.y, other * self.z)

    def __rdiv__(self, other):
        if isinstance(other, Vector):
            return Vector(other.x / self.x, other.y / self.y, other.z / self.z)
        else:
            return Vector(other / self.x, other / self.y, other / self.z)

    def __rtruediv__(self, other):
        if isinstance(other, Vector):
            return Vector(other.x / self.x, other.y / self.y, other.z / self.z)
        else:
            return Vector(other / self.x, other / self.y, other / self.z)

    def __iadd__(self, other):
        if isinstance(other, Vector):
            self.x += other.x
            self.y += other.y
            self.z += other.z
        else:
            self.x += other
            self.y += other
            self.z += other
        return self

    def __isub__(self, other):
        if isinstance(other, Vector):
            self.x -= other.x
            self.y -= other.y
            self.z -= other.z
        else:
            self.x -= other
            self.y -= other
            self.z -= other
        return self

    def __imul__(self, other):
        if isinstance(other, Vector):
            self.x *= other.x
            self.y *= other.y
            self.z *= other.z
        else:
            self.x *= other
            self.y *= other
            self.z *= other
        return self

    def __idiv__(self, other):
        if isinstance(other, Vector):
            self.x /= other.x
            self.y /= other.y
            self.z /= other.z
        else:
            self.x /= other
            self.y /= other
            self.z /= other
        return self

    def __itruediv__(self, other):
        if isinstance(other, Vector):
            self.x /= other.x
            self.y /= other.y
            self.z /= other.z
        else:
            self.x /= other
            self.y /= other
            self.z /= other
        return self

    def __getitem__(self, key):
        if not isinstance(key, int):
            raise KeyError(f'key: {key} must be interger')

        if key == 0:
            return self.x
        elif key == 1:
            return self.y
        elif key == 2:
            return self.z
        else:
            raise KeyError(f'key: {key} dose not exists')

    def __setitem__(self, key, val):
        if not isinstance(key, int):
            raise KeyError(f'key: {key} must be interger')

        if key == 0:
            self.x = val
        elif key == 1:
            self.y = val
        elif key == 2:
            self.z = val
        else:
            raise KeyError(f'key: {key} dose not exists')

    def __str__(self):
        return f'{self.x:.5f} {self.y:.5f} {self.z:.5f}'

    def __repr__(self):
        return f'{self.x:.1f} {self.y:.1f} {self.z:.1f}'

    def rotate_x(self, angle):
        rad = math.radians(angle)
        cos = math.cos(rad)
        sin = math.sin(rad)
        return Vector(self.x, cos*self.y-sin*self.z, sin*self.y+cos*self.z)

    def rotate_y(self, angle):
        rad = math.radians(angle)
        cos = math.cos(rad)
        sin = math.sin(rad)
        return Vector(cos*self.x + sin*self.z, self.y, -sin*self.x + cos*self.z)

    def rotate_z(self, angle):
        rad = math.radians(angle)
        cos = math.cos(rad)
        sin = math.sin(rad)
        return Vector(cos*self.x - sin*self.y, sin*self.x + cos*self.y, self.z)

    def rotate(self, angle, center=None):
        vec = Vector(self.x, self.y, self.z)
        if angle[0] != 0:
            if center is not None:
                vec -= center
            vec = vec.rotate_x(angle[0])
            if center is not None:
                vec += center

        if angle[1] != 0:
            if center is not None:
                vec -= center
            vec = vec.rotate_y(angle[1])
            if center is not None:
                vec += center

        if angle[2] != 0:
            if center is not None:
                vec -= center
            vec = vec.rotate_z(angle[2])
            if center is not None:
                vec += center

        return vec


class Vertex:
    def __init__(self, pos: Vector, uv: Vector):
        self.pos = pos
        self.uv = uv

    def translate(self, vec: Vector):
        self.pos += vec

    def scale(self, scale: Vector):
        self.pos *= scale

    def rotate(self, angle: Vector, center=None):
        self.pos = self.pos.rotate(angle, center)

    def to_smd(self, normal: Vector) -> str:
        # <int|Parent bone> <float|PosX PosY PosZ> <normal|NormX NormY NormZ> <normal|U V> [ignores]
        return f'0  {self.pos}  {normal}  {self.uv.x:.5f} {self.uv.y:.5f}'


class Face:
    def __init__(self, texture: str, vertices: List[Vertex], norm: Vector):
        self.tex = texture
        self.vert = vertices
        self.norm = norm

    def translate(self, vec: Vector):
        for v in self.vert:
            v.translate(vec)

    def scale(self, scale: Vector):
        for v in self.vert:
            v.scale(scale)

    def rotate(self, angle: Vector, center=None):
        for v in self.vert:
            v.rotate(angle, center)

    def to_smd(self) -> str:
        vert = self.vert
        builder = self.tex + '\n'
        builder += vert[0].to_smd(self.norm) + '\n'
        builder += vert[1].to_smd(self.norm) + '\n'
        builder += vert[2].to_smd(self.norm) + '\n'
        builder += self.tex + '\n'
        builder += vert[1].to_smd(self.norm) + '\n'
        builder += vert[3].to_smd(self.norm) + '\n'
        builder += vert[2].to_smd(self.norm) + '\n'
        return builder


class Cube:
    def __init__(self, position: Vector, size: Vector):
        self.size = size
        self.position = position
        self.faces = []

    def add_face(self, face: int, texture: str, uv: List[Vector]):
        if face == 0:  # east
            norm = Vector(-1.0, 0.0, 0.0)
            vertices = [
                Vertex(Vector(0.0, 1.0, 1.0), uv[0]),
                Vertex(Vector(0.0, 1.0, 0.0), uv[1]),
                Vertex(Vector(0.0, 0.0, 1.0), uv[2]),
                Vertex(Vector(0.0, 0.0, 0.0), uv[3]),
            ]
        elif face == 1:  # west
            norm = Vector(1.0, 0.0, 0.0)
            vertices = [
                Vertex(Vector(1.0, 0.0, 1.0), uv[0]),
                Vertex(Vector(1.0, 0.0, 0.0), uv[1]),
                Vertex(Vector(1.0, 1.0, 1.0), uv[2]),
                Vertex(Vector(1.0, 1.0, 0.0), uv[3]),
            ]

        elif face == 2:  # up
            norm = Vector(0.0, 0.0, 1.0)
            vertices = [
                Vertex(Vector(0.0, 1.0, 1.0), uv[0]),
                Vertex(Vector(0.0, 0.0, 1.0), uv[1]),
                Vertex(Vector(1.0, 1.0, 1.0), uv[2]),
                Vertex(Vector(1.0, 0.0, 1.0), uv[3]),
            ]

        elif face == 3:  # down
            norm = Vector(0.0, 0.0, -1.0)
            vertices = [
                Vertex(Vector(0.0, 0.0, 0.0), uv[0]),
                Vertex(Vector(0.0, 1.0, 0.0), uv[1]),
                Vertex(Vector(1.0, 0.0, 0.0), uv[2]),
                Vertex(Vector(1.0, 1.0, 0.0), uv[3]),
            ]

        elif face == 4:  # south
            norm = Vector(0.0, 1.0, 0.0)
            vertices = [
                Vertex(Vector(1.0, 1.0, 1.0), uv[0]),
                Vertex(Vector(1.0, 1.0, 0.0), uv[1]),
                Vertex(Vector(0.0, 1.0, 1.0), uv[2]),
                Vertex(Vector(0.0, 1.0, 0.0), uv[3]),
            ]

        elif face == 5:  # north
            norm = Vector(0.0, -1.0, 0.0)
            vertices = [
                Vertex(Vector(0.0, 0.0, 1.0), uv[0]),
                Vertex(Vector(0.0, 0.0, 0.0), uv[1]),
                Vertex(Vector(1.0, 0.0, 1.0), uv[2]),
                Vertex(Vector(1.0, 0.0, 0.0), uv[3]),
            ]

        # reference cube is center @ [0.5, 0.5, 0.5]
        face = Face(texture, vertices, norm)
        face.translate(Vector(-0.5, -0.5, -0.5))

        face.scale(self.size)
        face.translate(self.position)

        self.faces += [face]

    def translate(self, vec: Vector):
        for face in self.faces:
            face.translate(vec)

    def scale(self, scale):
        for face in self.faces:
            face.scale(scale)

    def rotate(self, angle: Vector, center=None, rescale=False):
        if center is not None:
            self.translate(-center)

        for face in self.faces:
            face.rotate(angle)

        if rescale:
            scaled = self.position.rotate(angle)
            scale = self.position.dot(
                self.position) / self.position.dot(scaled)  # porjection
            self.scale(Vector(scale, scale, 1))

        if center is not None:
            self.translate(center)

    def to_smd(self) -> str:
        builder = ''
        for face in self.faces:
            builder += face.to_smd()
        return builder

    def to_smdbones(self, center: Vector) -> str:
        return f'{center}  0.00000 0.00000 0.00000'


class SMDModel:
    def __init__(self):
        self.textures = {}
        self.cubes = []

        self.min = Vector()
        self.max = Vector()

    def add_cube(self, position: Vector, scale: Vector) -> Cube:
        cube = Cube(position, scale)
        self.cubes += [cube]
        return cube

    def translate(self, vec: Vector):
        for cube in self.cubes:
            cube.translate(vec)

    def to_smd(self) -> str:
        builder = ''
        for e in self.cubes:
            builder += e.to_smd()
        return builder

    def to_smdbones(self) -> str:
        builder = ''
        for i, e in enumerate(self.cubes):
            # assume it center at 0
            builder += f'{i} {e.to_smdbones(Vector())}\n'
        return builder


def export_texture(texture: str, texture_dir: str, out_dir: str) -> None:
    logger.info(f'Exporting texture: {texture}')

    out = os.path.normpath(os.path.join(out_dir, texture))
    if texture == '$missing':
        im = Image.open(io.BytesIO(base64.b64decode(missing_texture)))
    else:
        source = os.path.normpath(os.path.join(texture_dir, texture + '.png'))
        if not os.path.exists(source):
            logger.error(f'Texture file dose not exists: {source}')
            exit(1)

    im = Image.open(source)
    if im.format != 'PNG':
        logger.warning(f'Source texture is not PNG: {texture}')

    if im.mode != 'RGB' or im.mode != 'RGBA':
        im = im.convert('RGBA')

    meta = os.path.normpath(os.path.join(texture_dir, texture + '.png.mcmeta'))
    if os.path.exists(meta):
        with open(meta) as f:
            animation = json.load(f)['animation']

        # TODO:
        if 'frames' in animation:
            logger.warning(
                f'texture {texture} has "animation.frames", but was currently not supported')

        # minecraft animation 20 fps, it might cause some lag in csgo
        if 'frametime' in animation:
            frametime = 20 / animation['frametime']
        else:
            frametime = 20

        # slow it down or fps will drop when player up close
        frametime /= 2

        frame_size = im.width
        assert im.height % frame_size == 0, f'invalid animated texture: {texture}'

        proxy = VMT_PROXY_ANIMATION.format(frametime=frametime)
        textureDimens[texture] = Vector(frame_size, frame_size)

        save_vtf([
            im.crop((0, i * frame_size, frame_size, i * frame_size + frame_size))
            for i in range(0, im.height // frame_size)
        ], out + '.vtf')
    else:
        proxy = ''
        textureDimens[texture] = Vector(*im.size)
        save_vtf(im, out + '.vtf')

    cdmaterials = 'AMC/'
    with open(out + '.vmt', 'w') as f:
        f.write(VMT_MODELS_TEMPLATE.format(
            cdmaterials=cdmaterials, textire_file=texture, surfaceprop='', proxy=proxy))

    game_material = os.path.join(game_path, 'materials', cdmaterials, texture)
    shutil.copyfile(out + '.vmt', game_material + '.vmt')
    shutil.copyfile(out + '.vtf', game_material + '.vtf')


def resolve_texture(texture: str) -> str:
    if textureVars[texture][0] == '#':
        return resolve_texture(textureVars[texture][1:])
    return textureVars[texture]


def resolve_uv(texture: str) -> str:
    tex_file = resolve_texture(texture)
    if tex_file not in textureDimens:
        export_texture(tex_file, textures_path, out_textures_path)
    return tex_file


def convert_uv(mcuv: List[float], rotation=0) -> List[Vector]:
    mcuv = [v / 16 for v in mcuv]
    ref = [
        (mcuv[0], 1 - mcuv[3]),
        (mcuv[0], 1 - mcuv[1]),
        (mcuv[2], 1 - mcuv[3]),
        (mcuv[2], 1 - mcuv[1]),
    ]

    # source uv coordinate
    uv = [
        Vector(ref[1][0], ref[1][1]),
        Vector(ref[0][0], ref[0][1]),
        Vector(ref[3][0], ref[3][1]),
        Vector(ref[2][0], ref[2][1]),
    ]

    for i in range(rotation // 90):
        uv = [uv[1], uv[3], uv[0], uv[2]]

    return uv


def parse_model(models_path: str, model_file: str) -> List[str]:
    # TODO: handle namespace
    model_file = model_file.replace('minecraft:', '')

    with open(os.path.join(models_path, model_file + '.json')) as f:
        jmodel = json.load(f)

    idx = model_file.find('/')
    model_name = model_file[idx + 1:]

    logger.info(f'new qc: ' + model_file)
    qc = LineBuilder()

    textures = []
    undefined_textures = []

    if 'textures' in jmodel:
        qc('// JSON "textures":')
        for tex, val in jmodel['textures'].items():
            if ':' in val:
                val = val.split(':')[1]

            if val[0] == '#':
                # imported texture
                undefined_textures += [val[1:]]
                qc(f'$definevariable texture_{tex} $texture_{val[1:]}$')
            else:
                # real texture
                val = val.replace('minecraft:', '')
                qc(f'$definevariable texture_{tex} "{val}"')
                export_texture(val, textures_path, out_textures_path)

            # defined texture variable
            textures += [tex]
            assert tex not in textureVars, f'Texture varibale "{tex}" redefined'
            textureVars[tex] = val

        qc()

    if 'parent' in jmodel:
        parent_file = jmodel['parent']
        undefined_textures += parse_model(models_path, parent_file)

        idx = parent_file.find('/')
        qc(f'// JSON "parent":')
        qc(f'$include "{parent_file[idx + 1:]}.qci"')
        qc()

    if 'elements' in jmodel:
        qc(f'// JSON "elements"')
        qc(f'$definevariable mesh {model_name}')
        qc()

        model = SMDModel()
        model_textures = []

        for elem in jmodel['elements']:
            start = Vector(*elem['from'])
            end = Vector(*elem['to'])

            # the "height" of Source engine should be z
            start[0], start[1], start[2] = start[0], start[2], start[1]
            end[0], end[1], end[2] = end[0], end[2], end[1]

            size = end - start
            postiton = start + size / 2
            postiton = (postiton) * Vector(-1, 1, 1)
            cube = model.add_cube(postiton, size)

            logger.info(f'cube: {size} @ {postiton}')

            for facename, face in elem['faces'].items():
                texture = face['texture']
                if texture[0] != '#':
                    raise Exception(
                        'expect face texture to be a texture variable')

                # TODO: handle overlay texture, maybe by proxy
                if texture == '#overlay':
                    continue

                texture = texture[1:]
                if texture not in model_textures:
                    model_textures += [texture]

                if texture not in textureVars:
                    logger.warning(
                            f'texture variable "{texture}" was undefined, the model {model_file} might be template file')
                    if not args.allow_template:
                        logger.error(f'no missing texture was allowed, exiting')
                        exit(1)
                    else:
                        textureVars[texture] = '$missing'
                
                logger.debug(f'facename: {facename} -> {resolve_uv(texture)}')

                rotation = 0
                if 'rotation' in face:
                    rotation = face['rotation']

                uv = None
                if 'uv' not in face:
                    if facename in ['east', 'west']:     # yz plane
                        uv = [start.y, start.z, end.y, end.z]
                    elif facename in ['up', 'down']:     # xy plane
                        uv = [start.x, start.y, end.x, end.y]
                    elif facename in ['south', 'north']:  # xz plane
                        uv = [start.x, start.z, end.x, end.z]
                else:
                    uv = face['uv']

                uv = convert_uv(uv, rotation)

                # we need to rotate "up" and "down" face to match minecraft
                if facename in ['up', 'down']:
                    uv = [uv[3], uv[2], uv[1], uv[0]]

                cube_faces = {
                    "east":  0,
                    "west":  1,
                    "up":    2,
                    "down":  3,
                    "south": 4,
                    "north": 5,
                }
                cube.add_face(cube_faces[facename], f'@{texture}', uv)

            # now model center at (0, 0, 8), the buttom is on the ground
            cube.translate(Vector(8, -8, 0))

            if 'rotation' in elem:
                axis = elem['rotation']['axis']
                _angle = elem['rotation']['angle']

                if 'origin' in elem['rotation']:
                    origin = Vector(*elem['rotation']['origin'])
                else:
                    origin = Vector(8, 8, 8)

                rescale = False
                if 'rescale' in elem['rotation']:
                    rescale = elem['rotation']['rescale']

                angle = Vector()
                angle[0 if axis == 'x' else 1 if axis == 'y' else 2] = _angle
                angle[0], angle[1], angle[2] = -angle[0], angle[2], angle[1]

                origin[1], origin[2] = origin[2], origin[1]
                origin = origin - Vector(8, 8, 0)

                cube.rotate(angle, origin * Vector(-1, 1, 1), rescale)

        qc(f'// JSON "elements[].faces[].texture" list:')
        # use macro to replace texture variable
        qc(f'$definemacro applytextures \\\\')
        for tex in set(model_textures):
            if tex not in textures:
                undefined_textures += [tex]
            qc(f'$renamematerial "@{tex}" $texture_{tex}$ \\\\')
        qc()

        logger.info(f'New smd: {model_file}')
        with open(os.path.join(out_models_path, model_file + '.smd'), 'w', encoding='utf-8') as f:
            smd = LineBuilder()
            smd('version 1')
            smd('nodes')
            smd('000 "Cube" -1')
            smd('end')
            smd('skeleton')
            smd('time 0')
            smd(model.to_smdbones(), end='')
            smd('end')
            smd('triangles')
            smd(model.to_smd(), end='')
            smd('end')
            f.write(str(smd))

    require_textures = []
    for tex in undefined_textures:
        if tex not in textures:
            require_textures += [tex]

    real_model = len(require_textures) == 0 and len(textures) > 0

    qc_ext = '.qc' if real_model else '.qci'
    with open(os.path.join(out_models_path, model_file + qc_ext), 'w', encoding='utf-8') as f:
        if real_model:
            f.write(QC_HEADER.format(model_file=model_file))

        f.write(str(qc))

        if real_model:
            f.write(QC_FOOTER)

    return require_textures


parser = argparse.ArgumentParser(
    description='Convert MineCraft JSON model to Source engine model')

parser.add_argument('model', type=str,
                    help='minecraft model, e.g. "block/furnace_on"')

parser.add_argument('--tools', type=str, help='the folder contains studiomdl.exe',
                    default=r'C:\Program Files (x86)\Steam\steamapps\common\Counter-Strike Global Offensive\bin')
parser.add_argument('--game', type=str, help='the folder contains gameinfo.txt',
                    default=r'C:\Program Files (x86)\Steam\steamapps\common\Counter-Strike Global Offensive\csgo')
parser.add_argument('--assets', type=str,
                    help='path to minecraft assets folder')
parser.add_argument('-o', '--out', type=str,
                    help='output folder', default='csgo2')

parser.add_argument('--allow-template', type=bool,
                    action='store_true', default=False)
args = parser.parse_args()

tools_path = args.tools
game_path = args.game
assets_path = args.assets

textures_path = os.path.join(assets_path, 'textures')
models_path = os.path.join(assets_path, 'models')

out_dir = args.out
out_models_path = os.path.join(out_dir, 'modelsrc/')
out_textures_path = os.path.join(out_dir, 'materialsrc/')

model_base = os.path.join(out_models_path, 'modelbase_1.qci')
if os.path.exists(model_base):
    logger.info('creating modelbase_1.qci')
    os.makedirs(out_models_path, exist_ok=True)
    with open(model_base, 'w', encoding='utf-8') as f:
        print(QC_MODELBASE, file=f)

# TODO: dont use global variables
textureDimens = {}
textureVars = {}

json_model = args.json_model
parse_model(models_path, json_model)

cmd = f'"{os.path.join(tools_path, "studiomdl.exe")}" -game "{game_path}" -nop4 -nox360 "{os.path.join(out_models_path, json_model)}.qc"'

logger.debug(cmd)
ok, _, stdout = runcmd(cmd)
if not ok:
    logger.error(stdout.decode())

How to use it?