I'm mainly an AutoCAD and Revit user for architecture workflows. I don't have any professional surveyor training, but I know the fundamentals of coordinate systems including working with latitude, longitude and the conversion to state plane or other projected coordinate systems. I'd like to expand my knowledge into the surveying realm to enhance my abilities to create 3D topography and link site drawings containing geodetic location information into Revit.
In researching, I noticed that there are all kinds of GIS file types such as KML files, shapefiles, point clouds, CSV files, and many more. I know that Civil 3D and Map 3d are used to create surfaces with GIS information in files that have a coordinate system assigned to the drawing. I have linked such drawings into Revit using "location" tools available to create site plans. Apparently Revit doesn't natively recognize global or state plane coordinate systems yet. So, the Revit Survey Point stands in for a known global survey point. Revit can also create topography from DWGs with contour data or from CSV point files.
I'd like to explore creating my own DWG site plans with accurate location information within AutoCAD and then use those files to link into Revit for a site location, and then to use a DWG or CSV file to create an accurate 3D topography within Revit. I know that standard AutoCAD (without plugins) has some limited abilities to be assigned a projected coordinate system and import and use KML files compared to Civil 3D's more advanced abilities. I don't currently have access to a Civil 3D license, but I've looked at some tutorials to get started learning the basics.
So, what is a good beginner workflow and where can I best obtain accurate and affordable GIS files (shapefiles, KML files, CSV files) that contain street lines, building outlines, and elevation information? Are the best files obtained only by using an ArcGIS account and exporting from there? Which GIS files are of value to me? Are the free city/ county/ state files of any real value to me? I'd be looking for building, street, river outlines and for elevations at points. I've looked online and downloaded some simple KML files/ shapefiles (building outlines) of the entire city of Chicago but the file size was huge. AutoCAD (regular) could not even open it due to the multi GB size.
I've seen that I can draw polygons over a map background to represent streets and building outlines and then download the scene as a KML files from Google Earth. But, when I import those files into AutoCAD I don't see the polygons. It's also possible to simply import the map and just trace around all the streets and buildings in AutoCAD and use that as a simple "shapefile" containing an "accurate" location.
Do I need Civil 3D and an ArcGIS account to do anything of value in this realm? Is QGis freeware worth learning? Can any free software tools and downloads compete with paid GIS websites, downloads and software? What workflow and files are used when really accurate GIS information is needed by construction to position building components compared to creating an approximate site plan intended primarily for visualization?
Links to favorite GIS information/ map sites are welcome. I know that's a lot of questions, but any help is appreciated.
Thanks
