[SVRF] setting window size of "DENSITY" function using environment variables

Version 1

    Is it possible to set the size of window in "DENSITY" function using environment variable?

    I know that I can do it as follows:

    export env_var1=10 (in a shell)

     

    #IFDEF $env_var1 10

         #DEFINE env_var1 10

    #ELSE

         #IFDEF $env_var1 20

                   #DEFINE env_var1 20

         #ELSE

              #IFDEF ...

     

    I wonder whether I can directly set the size of window using an environment variable without writing multiple if-else clauses.