Possibly save 1 hour of your time: If you are using schema compare in your database solution project within Visual Studio, the initial compare shows nothing on the project vs your target database. It tells you the difference is to delete all objects such as tables and stored procedures.
The problem was that the scripts (.sql) files are added to the folder outside of Visual Studio. You need to right click on the folder and choose Add >> New Item. Then you can select under each SQL Server menu sub category and the SQL object.