FAQ 1   -   INPUT & DATA IMPORT
Q.	What is the format of the imported ASCII data?
A.	This file should contain Width x Height floating point numbers in a text file. Each value corresponds to a Z (height) value of the height matrix. These numbers are loaded row wise, so the first Width numbers will be the first row of the landscape. For purposes of comparison and testing, we have prepared a sample ASCII text data file. ASCII DEM Data in regular Zip format; ASCII DEM Data in WinZip .exe self-extracting format.
Q.	What is the format of the imported RAW data?
A.	This is like the binary version of the ASCII format except it supports integers only. Generally speaking this is a standard RAW format file that can be opened as an image in Adobe Photoshop. Each value contains a height value. Data is loaded row wise. Data format can be 8 or 16 bits signed or unsigned. Byte order can be Macintosh or PC. For purposes of comparison and testing, we have prepared a sample RAW format file. RAW DEM Data in regular Zip format; RAW DEM Data in WinZip .exe self-extracting format.
Q.	Where can I obtain seamless DEM data from the USGS?
A.	Seamless DEM data available from the USGS National Elevation Dataset web site at http://seamless.usgs.gov/ can be downloaded at no cost providing the file sizes remain under a specified size, generally 100 MB. File larger than the limit are written to CDR and shipped for a modest price. Follow the prompts for View and Order Data Sets selecting either United States or International. For the US, a National Map will appear - alternatively either click, hold down cursor and drag an area on the map to select your area of interest, or, preferably, click on Define Area by Coordinates found in the left panel towards the bottom of the screen. This approach allows a specific quad to be selected and enables exact matches when combining multiple map resources. Confirm the selected area. When the SDDS Request Summary Page appears, click Modify the Request to specify the format, altering the ArcGrid format to BIL for the selected NED - National Elevation Dataset, and choosing ZIP for the download compression. At this stage also remove any other unwanted data selections. Click on Save Changes and Return to Summary. Proceed with Download. For detailed instructions on processing the data into MapRender3D check the next question below.
Q.	How do I work with the USGS seamless DEM data once I get it?
A.	Firstly unzip the NED dataset and locate the .bil file (it will be the biggest file size of the group). Second, open the .hdr file using a text editor and note the NROWS and NCOLS value, and the NBITS value - these will be used shortly. The contents are shown in the image alongside. Third, rename the .bil data set as .raw - shorten up the name so that there is only one dot extension. Fourth, open MapRender3D and select 'Load Height data' and change the type to 'raw'. Fifth, next a dialog window (shown below) will appear for you to enter the DEM dataset parameters. For data options, select NCOLS value x NROWS value for width and height, 16 bit and unsigned, select IBM PC - if the NBITS was set to 8 bits no Mac/IBM box appears. Generally the Header is zero for files of this type; also switch off Automatic Elevation Data Boundaries. Any remaining information can remain blank or as default. Sixth, click OK and proceed with the MapRender renderings as normal.
Q.	Error using Convert when you open a PSB file - gives the message "Error! Database reading error!"
A.	1 - Copy the 1kmglobe.psb or other .psb from the Install CD to C:\program files\GHZ\Maprender3d directory were the MapRender3D was installed to - see picture below. 2 - Double click the icon for the copied PSB file
Q.	OUTPUT & IMAGE EXPORT
A.	Issues and FAQ's relating to image export....... more details
Q.	MAP PROJECTION
A.	Issues and FAQ's relating to map projections....... more details
Q.	MAPRENDER3D OPERATIONS
A.	Issues and FAQ's relating to running the MapRender3D application....... more details