Embed 3D models (U3D) in PDF files using Python

#---------------------------------------------------------------------------------------
# Copyright (c) 2001-2023 by Apryse Software Inc. All Rights Reserved.
# Consult LICENSE.txt regarding license information.
#---------------------------------------------------------------------------------------

import site
site.addsitedir("../../../PDFNetC/Lib")
import sys
from PDFNetPython import *

sys.path.append("../../LicenseKey/PYTHON")
from LicenseKey import *

# Relative path to the folder containing the test files.
input_path = "../../TestFiles/"
output_path = "../../TestFiles/Output/"

def Create3DAnnotation(doc, annots):
    # ---------------------------------------------------------------------------------
    # Create a 3D annotation based on U3D content. PDF 1.6 introduces the capability 
    # for collections of three-dimensional objects, such as those used by CAD software, 
    # to be embedded in PDF files.
    link_3D = doc.CreateIndirectDict()
    link_3D.PutName("Subtype", "3D")
    
    # Annotation location on the page
    link_3D_rect = Rect(25, 180, 585, 643)
    link_3D.PutRect("Rect", link_3D_rect.x1, link_3D_rect.y1,
                    link_3D_rect.x2, link_3D_rect.y2)
    annots.PushBack(link_3D)
    
    # The 3DA entry is an activation dictionary (see Table 9.34 in the PDF Reference Manual) 
    # that determines how the state of the annotation and its associated artwork can change.
    activation_dict_3D = link_3D.PutDict("3DA")
    
    # Set the annotation so that it is activated as soon as the page containing the 
    # annotation is opened. Other options are: PV (page view) and XA (explicit) activation.
    activation_dict_3D.PutName("A", "PO")  
    
    # Embed U3D Streams (3D Model/Artwork).
    u3d_file = MappedFile(input_path + "dice.u3d")
    u3d_reader = FilterReader(u3d_file)
    
    u3d_data_dict = doc.CreateIndirectStream(u3d_reader, FlateEncode(Filter()))
    u3d_data_dict.PutName("Subtype", "U3D")
    link_3D.Put("3DD", u3d_data_dict)
    
    # Set the initial view of the 3D artwork that should be used when the annotation is activated.
    view3D_dict = link_3D.PutDict("3DV")
    
    view3D_dict.PutString("IN", "Unnamed")
    view3D_dict.PutString("XN", "Default")
    view3D_dict.PutName("MS", "M")
    view3D_dict.PutNumber("CO", 27.5)
    
    # A 12-element 3D transformation matrix that specifies a position and orientation 
    # of the camera in world coordinates.
    tr3d = view3D_dict.PutArray("C2W")
    tr3d.PushBackNumber(1)
    tr3d.PushBackNumber(0)
    tr3d.PushBackNumber(0) 
    tr3d.PushBackNumber(0) 
    tr3d.PushBackNumber(0) 
    tr3d.PushBackNumber(-1)
    tr3d.PushBackNumber(0) 
    tr3d.PushBackNumber(1) 
    tr3d.PushBackNumber(0) 
    tr3d.PushBackNumber(0) 
    tr3d.PushBackNumber(-27.5) 
    tr3d.PushBackNumber(0)
    
    # Create annotation appearance stream, a thumbnail which is used during printing or
    # in PDF processors that do not understand 3D data.
    ap_dict = link_3D.PutDict("AP")
    
    builder = ElementBuilder()
    writer = ElementWriter()
    writer.Begin(doc.GetSDFDoc())
    
    thumb_pathname = input_path + "dice.jpg"
    image = Image.Create(doc.GetSDFDoc(), thumb_pathname)
    writer.WritePlacedElement(builder.CreateImage(image, 0.0, 0.0, link_3D_rect.Width(), link_3D_rect.Height()))
    
    normal_ap_stream = writer.End()
    normal_ap_stream.PutName("Subtype", "Form")
    normal_ap_stream.PutRect("BBox", 0, 0, link_3D_rect.Width(), link_3D_rect.Height())
    ap_dict.Put("N", normal_ap_stream)

def main():
    PDFNet.Initialize(LicenseKey)
    
    doc = PDFDoc()
    page = doc.PageCreate()
    doc.PagePushBack(page)
    annots = doc.CreateIndirectArray()
    page.GetSDFObj().Put("Annots", annots)
    
    Create3DAnnotation(doc, annots)
    doc.Save(output_path + "dice_u3d.pdf", SDFDoc.e_linearized)
    doc.Close()
    PDFNet.Terminate()
    print("Done.")

if __name__ == '__main__':
    main()