Changes between Version 6 and Version 7 of AlsprocDevelopment

Timestamp:

Aug 16, 2013, 4:58:59 PM (11 years ago)

Author:

besm

Comment:

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AlsprocDevelopment

@@ -19 +19 @@
 
 SCN reading is arguably the most complex part of the program. It's best not to debug it directly in alsproc if at all possible, as this bars the use of gdb. Instead, consider using the scn_info program, which is compiled normally but still uses the same code for reading SCN records.
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+== GTX Files ==
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+As ARSF often delivers data projected in the British National Grid, and Alsproc performs all projection operations using proj.4, performing the OSGM02 transformation specified by Ordnance Survey is essential to producing vertically accurate data. proj.4 can only perform grid-shift transformations vertically using .gtx files. For this purpose, a .gtx file had to be produced from the Ordnance Survey data from their website. You may need to produce or fine tune a .gtx file, so the tools used to generate them have been retained and are available in the svn repository under tools/gtx/.
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+You also require proj of at least version 4.8.0, the source code is available online, but be warned that as of the time of writing this doesn't compile out-of-the-box. It will compile, but requires minor adjustments to one source file and possibly the Makefile.