How to develop, to a program debug-version ascii inside lisp, before Vlx?>
How to install the programe AutoLisp work in once Drawing.File?
How to downloading DCL from the forum on the web,?
How develop the Libraries/files .zipped with Lisp source?
How build the file language.lng file for yourProgram.Lisp?
How to move all messages from the programe.lisp.lsp , to inside yourDrawing.dwg?
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If you need, extend the AutoCad-Drawing a long-term (many , many year/s) with visual-lisp-extra function/s
+1) then you must develop VLisp-Applet/s as zip files, and all program/s lisp contain many test/s of code-lisp.
+2) you must prepare the mix Drawings+AutoLisp+Notepad++Blade-insideBricsCad..

That reason you need use, the any AutoLisp-Generator, C# ,java ,.exe...
You must use many compilator/s of VLISP (Vlide+Blade+7ZipFm+VlaxCompilr+DclGenerator+C#+)

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Can we transform DrafterWorker to youtube-funny-movies?
https://youtu.be/-oWigoQzy0s

Please your images PDFs or JPEGs must have, >=300dpi.,.
If your PDF have dpiSize<300dpi then i have tool PDF-corectionpDPI.exe
PDF-corectionpDPI.exe , may be fail , if your PDF have bugs or problems,.,.
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Already i vectorize images to geographic dwg maps inside the autocad..
I understand your task,,
you need "calibrate" the jpeg/ and drawing in foreground on this jpeg.
.(you can draw the spline, polylline, circles...)