Automating 3D Scene Creation in Cinema 4D with Python: From CAD to VR

Overview

With the rapid growth of offline business at 58 Daojia, the demand for store design and renovation has surged. By leveraging a VR platform, the company can visually present design concepts, align stakeholder goals, and ensure high‑quality implementation.

Technical Approach

The solution uses Cinema 4D (C4D) together with Python to automate the creation of 3D scenes from CAD files. C4D can import AutoCAD files, read layer and block information, and then construct walls and place furniture accordingly.

Workflow Steps

CAD layer and block preparation : Separate CAD layers for different objects (e.g., glassdoor, wall, glasswall) and create corresponding furniture blocks.

Model preparation in C4D : Import or model objects, match model names to CAD layer names, and set the model’s pivot to the bottom‑center.

Python scripting : Use the C4D Python API to read CAD data, build walls, create door and window openings, place doors, windows, furniture, lights, and cameras.

Key Code Snippets

def getlayers(self, name=None):
    dic = {}
    for layer in self.layers(mode='all'):
        dic[layer] = []
        for obj in self.childrens():
            if obj.GetLayerObject(doc)[c4d.ID_BASELIST_NAME] == layer:
                dic[layer].append(obj)
        continue
    if name is None:
        return dic
    return dic[name]

def createWall(self, up=None):
    connect_wall = c4d.BaseObject(1011010)
    connect_wall[c4d.CONNECTOBJECT_WELD] = 0
    connect_wall[c4d.CONNECTOBJECT_PHONG_MODE] = 3
    if up is None:
        self.doc.InsertObject(connect_wall)
    else:
        self.doc.InsertObject(connect_wall, up)
    # ... create foot, wall extrusion, set materials, build spline connections ...
    c4d.EventAdd()
    return connect_wall

def subtractWindow(self):
    extruding = c4d.BaseObject(5116)
    extruding[c4d.EXTRUDEOBJECT_EXTRUSIONOFFSET] = self.WINDOWUP - self.WINDOWDOWN
    extruding[c4d.ID_BASELIST_NAME] = self.WINDOWNAME
    extruding[c4d.ID_BASEOBJECT_ROTATION_ORDER] = 5
    extruding[c4d.ID_BASEOBJECT_REL_POSITION, c4d.VECTOR_Y] = self.WINDOWDOWN
    extruding[c4d.ID_BASEOBJECT_REL_ROTATION, c4d.VECTOR_X] = c4d.utils.DegToRad(-90)
    return extruding

def setDoors(self, hardData):
    harddata = hardData.GetChildren()
    for obj in harddata:
        for layername, splines in self.layersdic.items():
            if obj[c4d.ID_BASELIST_NAME] == layername and 'door' in layername:
                for spline in splines:
                    pos = spline.GetAbsPos()
                    length_vec, angle_vec = self.getSplineAngle(spline)
                    newobj = obj.GetClone()
                    newobj = self.stretchModel(newobj, length_vec, self.DOORHEIGHT, self.DEFAULT_DOORSIZE)
                    newobj.SetAbsPos(c4d.Vector(pos.x, 0, pos.y))
                    newobj.SetAbsRot(angle_vec)
                    self.doc.InsertObject(newobj)
                    c4d.EventAdd()
    return True

def CreateLight(self, pos, size):
    obj = c4d.BaseObject(5102)
    obj[c4d.LIGHT_TYPE] = 8
    obj[c4d.ID_BASEOBJECT_REL_POSITION] = c4d.Vector(pos.x, self.LIGHTHEIGHT, pos.y)
    obj.SetRotationOrder(c4d.ROTATIONORDER_XYZGLOBAL)
    obj[c4d.ID_BASEOBJECT_REL_ROTATION] = c4d.Vector(-1.571, 0, 0)
    obj[c4d.LIGHT_AREADETAILS_SIZEX] = size.x * self.SCALE
    obj[c4d.LIGHT_AREADETAILS_SIZEY] = size.y * self.SCALE
    # add light tag settings ...
    obj.InsertTag(tarTag1)
    doc.InsertObject(obj)
    c4d.EventAdd()
    return obj

def setCamera(self, pos):
    campos = c4d.Vector(pos.x, self.POSY, pos.y)
    camobj = c4d.BaseObject(5103)
    camTag = c4d.BaseTag(1029524)
    camTag[1439] = 1
    camTag[c4d.OCTANECAMERA_ENABLE_IMAGER] = 1
    camTag[c4d.OCT_CAMIMAGER_EN_DENOISER] = 1
    camTag[c4d.OCTANECAMERA_EXPOSURE] = 4.0
    camTag[c4d.OCTANECAMERA_HCOMPRESSION] = 1.0
    camTag[c4d.OCT_CAMERA_IMAGER_ORDER] = 1
    camTag[c4d.OCTANECAMERA_RESPONSE] = 5221
    camTag[c4d.OCTANECAMERA_NAT_RESPONSE] = 1
    camTag[c4d.OCTANECAMERA_GAMMA] = 4.0
    camobj[c4d.CAMERAOBJECT_SHOW] = 0
    camobj.InsertTag(camTag)
    camobj.SetRelPos(campos)
    doc.InsertObject(camobj)
    c4d.EventAdd()
    return camobj

Result

By combining CAD data extraction with C4D’s modeling capabilities, the workflow automatically builds walls, doors, windows, places furniture, and adds lighting and camera setups, producing ready‑to‑render VR scenes that streamline interior design visualization.