Terrain and Imagery Manual

For Golf Course Architect Software

By: Brian Zager

Introduction

This manual details using elevation data and imagery in creating digital models of golf courses. The courses are used for play on computers and simulators or to create visual renderings. The purpose of this manual is to maximize accuracy in a relatively simple, repeatable process.

There are three major parts to the process in using imagery and elevation data.

  • Data Sources - Finding and downloading data.
  • GIS Mapping Software - Working with data in mapping software known as Geographic Information System (GIS) software.
  • Golf Architect Software - Importing data into specialized golf architect software.

A lot of the research involved in arriving at this process is included in the manual. In particular the manual goes into detail on using GIS software. The primary GIS software program coveredis Global Mapper. It is somewhat expensive but allows for greater accuracy with less effort than other tools. Some of this detail is not applicable without Global Mapper or if attention to detail is not a priority. There is a section on using free or less expensive tools for those without Global Mapper.

The manual includes steps designed to stand outfor those with background knowledge already or do not want to know the reasons behind the decisions made to develop the process. This is not however a process where you follow every step in the manual from beginning to end. Rather it is a guide broken down into sections for doing different processes you may encounter. Not all of these sections are applicable to every project or person. Different projects require different combinations of Data Sources, GIS Software, and Golf Architect Software.

The table below is designed to help you build a step by step process of only what is required for a given project. It contains the sections with instructions on the left and some typical scenarios across the top. The sections used by a scenario are marked.

Sections for Typical Scenarios

(LiDAR, GeoComm, Golf Architect Software, Global Mapper, Free Tools, Red Chain, Headgate)

  • Elevation Data()
  • 135LiDAR
  • 4GeoComm
  • 2Golf Architect Software
  • Imagery(LiDAR, GeoComm, Golf Architect Software)
  • 12345SAS.Planet
  • Global Mapper
  • GIS Software(Global Mapper, Rectifying, Free Tools)
  • 125Display Projection
  • 2Rectifying a DXF Mesh
  • 125Gridding Data
  • 125Define the Plot
  • 343DEM
  • Golf Architect Software (Red Chain, Headgate)
  • 123Red Chain (CPG / WGC / Simulators)
  • 45Headgate (PGA 2000 / Tiger Woods Series)
  1. LiDAR using Global Mapper exporting to Red Chain
  2. PGA 2000 Data using Global Mapper exporting to Red Chain
  3. LiDAR using free GIS tools exporting to Red Chain
  4. NED using free GIS tools exporting to PGA 2000
  5. LiDAR using Global Mapper exporting to PGA 2000

Table of Contents

  • Introduction
  • Imagery and Elevation Data
  • Scenarios
  • Chapter 1: Data Sources
  • Part 1: Elevation Data
  • Quality
  • LiDAR
  • Data
  • Downloading
  • DEM
  • Data
  • Downloading
  • The National Map
  • GeoComm
  • Golf Architect Software
  • Part 2: Imagery
  • Quality
  • Sources
  • Downloading
  • SAS.Planet
  • Downloading Sources
  • Google Earth
  • Global Mapper
  • Map APIs
  • Chapter 2: GIS Mapping Software
  • Part 1: Global Mapper
  • Map Projection
  • Display Projection
  • Projection Distortion
  • Zero Dimension
  • Transverse Mercator Projection
  • Other Projections
  • Measuring Distortion
  • Angular Distance Measurement
  • Loading Data
  • Unknown Source Projection
  • Rectifying
  • Rectifying a DXF Mesh
  • Manual Adjustments to a Projection
  • Projection Parameters
  • Coordinate Transformation Shift
  • Measuring an Offset Adjustment
  • Gridding Data
  • Define the Plot
  • Input the Size of a Square
  • Create a Shape from a Source
  • Freehand Draw
  • Part 2: Free Tools
  • 3DEM
  • Chapter 3: Golf Architect Software
  • Part 1: Red Chain (CPG / WGC / Simulators)
  • Elevations
  • Elevation Resolution (Global Mapper)
  • Tile Offsets and Converting to DXF (Global Mapper)
  • Elevation Data Import
  • Imagery
  • Tile Offsets for Imagery (Global Mapper)
  • Blueprint Tool
  • Drawing Shapes
  • QCAD
  • Loading Imagery (Global Mapper)
  • Drawing Shapes
  • Shape Import
  • Part 2: Headgate (PGA 2000 / Tiger Woods Series)
  • Stuff goes here
  • Appendix A: Commonly Used Functions
  • Global Mapper Functions
  • Excel Functions

Chapter 1: Data Sources

Part 1: Elevation Data

Elevation data is a digital representation of real world terrain. It is used to generate plot wide elevations for doing real course renditions or fictional courses based on real locations.

Elevation Data Quality

How accurate elevation data is depends on its resolution. It is similar to the resolution of an image. Instead of pixels,elevation data is agrid of measured elevation points. A higher resolution produces sharper detail. The resolution is measured by how far apart the points are. A 1 meter resolution file is higher resolution than a 10 meterbecauseeach measured point on the grid is separated by only 1 meter instead of 10 meters. It is typically measured in meters although sometimes measured in feet.

Expected results from different resolution data are listed below.

  • 5 meter – Most elevations come in accurately. Sharp edges get rounded off so things like bunker lips or edges of tees and greens may need fixing.
  • 5to 30 meter– Good plot scale elevations but manual detail work is needed for things like green contours, mounding, bunker shaping, tee boxes, etc.
  • > 30 meter – Not very useful unless except for extreme elevation changes.

There is also vertical resolution which indicates how accurate elevation measurements are. This is typically about 0.1 meters. A resolution referred to is typically not the vertical resolution unless it is specifically stated as such.

LiDAR Data

Light Detection and Ranging (LiDAR) data is elevation data scanned using lasers. It is similar to radar except it uses laser light instead of radio waves. Using the known speed of light, the timing of the laser beam reflection back to the source is used to determine the distance traveled. Typically for elevation data this is done from an airplane. Reflections of trees, buildings or other objects are tagged and removed so only the land height data remains.

LiDAR in its raw form varies in resolution depending on the amount of obstructions in the scanned area. It is typically high resolution (1 to 3 meter) across most areas though and there are minimal obstructions over the inplay areas of golf courses.

LiDAR Downloads

Governments gather most of this data and as a result a lot of it isin the public domain, available free to download. Currently it is not aggregated on one central site though. There are a few national sites for the US with spotty coverage:

The best thing to do however is to Google “LiDAR” along with the state, county or city of the location you are looking for. For about half of the state of Wisconsin LiDAR data is available at (requires creating a free user account).

DEM Data

A Digital Elevation Model (DEM) is astandardized format many different types of elevation data use. In some cases downloadedLiDAR is already processed into a DEM file.

The United States Geological Survey (USGS) created a National Elevation Dataset (NED) compiled from multiple sources. It primarily uses survey maps but also combines digital photogrammetry and some LiDAR and Interferometric Synthetic Aperture Radar (IfSAR) which is a form of scanning using radar. If there is not specific LiDAR available for the area you need, this is typically your next best option. Resolution is as high as 1 meter (1/9 arc second) in some areas while othersare only 30 meter (1 arc second) but most of the US is at least available in 10 meter (1/3 arc second) resolution.

DEM Downloads

Below is a list of common sources forDEMdownloads:

  • The National Map - Primary source for downloading NED data for Global Mapper.
  • GeoComm - NED data in a file format that free tools are able to open. Changes to the NED are not always updated here as soon as they are on The National Map.
  • GeoBase - DEM Coverage of Canada.
  • NetGIS - DEM coverage of Europe.

This tutorial goes into detail on downloading from the following sources:

  • The National Map - adf, flt, img, all work in global mapper, img is smallest, cancel picking projection for shape, close other shape overlay
  • GeoComm

Golf Architect Software

Some golf architect software allows you to export elevations asa meshto useas a very high resolution data source. This is useful for transferring manual elevation work to other golf architect software. It saves the need to redo work already done when recreating fictional courses or real courses where no high resolution LiDAR data exists.

Below are the steps for exporting a mesh from PGA 2000 or the Tiger Woods software.

  1. Load the architect file.
  2. Push Ctrl + []
  3. Enter a name for the export file, choose a location, and save it.

Part 2: Imagery

Using satellite and other aerial imagery as a transparency over your plot allows you to accurately trace fairways, greens, tees, water, etc. and place objects in the correct location on your plot.

Image Quality

Generally a higher resolution image makes it easier to layout your course. This tutorial explains how to get the highest resolution image from your source. It's not the only factor though. Shadows, the season an image was taken in, how old an image is, etc. sometimes make different parts of your image difficult to use or inaccurate. Because of this it is better to use multiple images if they are available for your location.

Imagery Sources

Below is a list of common sources for imagery downloads:

  • Google Earth/Maps - High resolution color imagery around the world. No complete coverage of any specific area.
  • Microsoft Virtual Earth - High resolution color imagery around the world. Complete coverage of the US.
  • USGS Seamless - Black and white imagery and topographic maps covering the entire US. Color Imagery in some areas.
  • TerraServer - of the same imagery available from USGS Seamless.

Downloading Imagery

There are several programs for downloading imagery.

  • SAS.Planet
  • Terra Incognita
  • Global Mapper
  • Google and Microsoft APIs

This tutorial goes into detail on

  • SAS.Planet – This program makes downloading imagery from many different sources the easiest.
  • Global Mapper
  • Google and Microsoft APIs - Mostly here for historical reasons as a backup plan. I developed this method before programs existed for doing the same task.

Downloading

One source for downloading NED data is The National Map ( /)

  1. Zoom in to the area you want to download.
  2. Click on Download by Bounding Box
  3. Draw a box around the area you want to download.
  4. Put a check mark next to Elevation and click next.
  5. You may also wish to put a check box in US Topo, Orthoimagery and Contours.
  6. Put a check next to the best resolution available (typically 1/3 arc-second).

The three formats available are ArcGrid, IMG, and GridFloat. Global Mapper can open any of them. In the comparisons I did there was no detectable difference in quality but the IMG file type had a slightly smaller file size so this is the file type I use. Unfortunately the free tools I’m familiar with aren’t able to open any of these formats.

  1. Click the Checkout button.
  2. Enter an e-mail address and click the Place Order button.
  3. When you receive an e-mail click on the Click here to download link.

GeoComm

GeoComm is an alternate source for downloading NED data. Without Global Mapper this is the best place to download data as it is in a file format that free tools I’m familiar with are able to open. This is a 3rd party site so changes in the NED are notalways updated as soon as they are on the USGS’s own site, The National Map.

To get started you need to register for a free account on the GeoComm Site. Once you log in you're ready to start looking for the DEM. The site sorts tiles by state, county and city. If you know the town or city where your course is located try doing a Google search to find the county in which it resides. Another way to find the county is to gradually zoom out in Google Earth until it displays counties.

  1. Open the GeoComm Site and select the state your course is located in.
  2. Select the county the course is located in.
  3. Select the first item on the list "Digital Elevation Models (DEM) - 24K".
  4. Select the city or town your course is near and click on the green download button to the right.
  5. Depending on your location, there is sometimes more than one resolution option to download. Download the highest resolution available. For more on resolutions see the DEM Overview. [link]

SAS.Planet

SAS.Planet is a free program for downloading and stitching together imagery from many sources on the internet including Google and Microsoft. Their website, SASGIS is in Russian but the program at the option to work in English. To download it click the button with the green arrow pointing down on the top right side of the page. This takes you to a page of different versions but after waiting 10 seconds the latest stable release download automatically starts. They also have an older archived site but downloads do not work there anymore. For a rough translation of the webpages use Google Translate [link] and paste in the URLs. The information and instructions I’ve written below hopefully prevent you from needing to do this.

Some data sources block you for a period of time if you download too much. For example, Google blocks you from downloading more than around 500 MB of satellite imagery at a time from Google Maps. If you pass this mark you typically can’t view new imagery for 24-48 hours in any application that uses the maps APIon the desktop or web. Google Earth still works because it is separate from the Google Maps API. If a zoom level of about 22 or better is available, this is becomes a problem for downloading imagery of an entire course. SAS.Planet caches imagery to help avoid hitting caps and avoid wasting bandwidth on something already downloaded. This cache is still visible while you are blocked from downloading new content.

Bulk downloading breaks the terms of service for most companies but it is primarily concerned with downloading on a much larger scale then the size of a golf course. There is questionable legality but since the companies do not offer an official way to download imagery, paid or not, it is currently the nature of things. Do take this into consideration however and limit downloads to your needs.

Below are instructions for downloading and saving imagery. This includes satellite imagery from Google Maps but not Google Earth. There are special instructions for accessing imagery only available through Google Earth.

  1. Find the area you want to download imagery.

To pan, click and drag with the left mouse button.

To zoom use the mouse wheel or side bar button navigation.

  1. Click on the Selected Basemap button on the toolbar.

This is the button that says the name of the data source currently selected. The default is Satellite (Google maps).

  1. Select adata source.

There are many choices including satellite imagery, street maps, and topo maps. Many of the sources are for specific parts of the world. Some good sources to try for imagery in the US or globally include:

  • Google > Satellite (Google Maps)
  • Bing > Bing Maps – Satellite
  • Bing > Bing Maps - Bird’s Eye North
  • Yahoo! > Satellite (Yahoo!)
  • ESRI > ArcGIS.Imagery
  1. Find the highest resolution zoom level available.
  2. Zoom in one level at a time, moving toward the same location on the course you zoomed into on Google Earth LOCAL, until the image disappears.
  3. Zoom back out one level and make a note of the zoom number.

This is the maximum zoom level for that image. Usually it is in the usually in the 18-22 range. If the image does not disappear and only appears more pixelated you need to change the Use Maps from Lower Zooms setting. [link]

  1. Create a selection box covering the area you want to download.
  2. Click on the Selection Manager button and choose Rectangular Selection.

Selection Manager is second from left on the toolbar.

  1. Click one corner of the area you want to download.

The mouse begins drawing a blue box to outline the download area.

  1. Click the opposite corner of the area you want to download.

The area inside the blue box is what is downloaded if you proceed.

The Selection Manager dialog box pops up.

  1. On the Download Tab under the Map: choose the source you want to use from the drop down.
  2. Under Zoom: choose the highest level zoom level you found earlier.
  3. Check Try to re-download missing tiles.
  4. Click Start.

SAS.Planetshows a progress bar for downloading.

  1. Click the Quit Button when it is finished downloading.

Stitching Tiles