Class CMProj4Grid extends CMProjector
  CMProj4Grid
 
  Projects data based on a grid.  This class uses a URL to a Proj4 grid file as created
  by the associated Python script.  This file is used when the user just wants to specify
  a single projection grid.  Otherwise, CMProj4WebService should be used which inherits
  from this class and allows various settings to be specified and a web service call will
  then produce a new grid for those settings.
 
  
  Copyright (C) 2020, Humboldt State University, Jim Graham 
  
  This program is free software: you can redistribute it and/or modify it under the terms of the GNU General 
  Public License as published by the Free Software  Foundation, either version 3 of the License, or (at your 
  option) any later  version. 
   
  This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the 
  implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 
  for more details. 
  
  You should have received a copy of the GNU General Public License along with this program. If not, see 
  .
Settings Group: Proj4Grid
| Setting | Name | Type | Options | Default | Comments | 
| URL | URL | CMTYPE_STRING |  | /Archive/ProjectionGrids/robin/BB=-180_-90_180_90/DegreeSpacing=10/ |  | 
Settings Group: Projection
Object Functions
Object Functions 
an=GetClippingPolys()
 Returns clipping bounds that can be used to clip geographic data for the current
 projection settings
Returns: an - array of clipping polys [Xs[],Ys[]]
RequestGrid()
 Requests a grid specified by a URL
RequestBackProjectionGrid()
 Requests a grid specified by a URL
CoordinateInside()
 Requests a grid specified by a URL