From 845f700335fb31318acf831bc42d62a230478eae Mon Sep 17 00:00:00 2001
From: Martin Dobias <wonder.sk@gmail.com>
Date: Sun, 23 Feb 2020 21:46:47 +0100
Subject: Add alternative grid for JTSK - JTSK03 transform (EPSG:8364)

The definition of EPSG:8364 uses NADCON method for horizontal grid (.las/.los files)
but this format is not supported by PROJ.

UGKK (Slovak Geodetic and Cartographic Institute) provides NADCON .las/.los files here:
https://www.geoportal.sk/files/gz/slovakia_jtsk03_to_jtsk.zip

Additionally UGKK also provides the same grid file in NTv2 format:
https://www.geoportal.sk/files/gz/slovakia_jtsk03_to_jtsk_ntv2.zip

So let's add the NTv2 file the grid_alternatives table so that PROJ can automatically pick it up...
---
 data/sql/grid_alternatives.sql | 8 ++++++++
 1 file changed, 8 insertions(+)

(limited to 'data/sql/grid_alternatives.sql')

diff --git a/data/sql/grid_alternatives.sql b/data/sql/grid_alternatives.sql
index b9c2e323..e545c7bf 100644
--- a/data/sql/grid_alternatives.sql
+++ b/data/sql/grid_alternatives.sql
@@ -176,6 +176,14 @@ VALUES
 ('Icegeoid_ISN2016.gtx','is_lmi_Icegeoid_ISN2016.tif','Icegeoid_ISN2016.gtx','GTiff','geoid_like',0,NULL,'https://cdn.proj.org/is_lmi_Icegeoid_ISN2016.tif',1,1,NULL),
 -- New Zealand grid shift models.
 ('auckland-1946-to-nzvd2016-conversion.csv','nz_linz_auckht1946-nzvd2016.tif','auckht1946-nzvd2016.gtx','GTiff','vgridshift',0,NULL,'https://cdn.proj.org/nz_linz_auckht1946-nzvd2016.tif',1,1,NULL),
+-- Slovakia
+--
+-- The definition of EPSG:8364 (JTSK03 to JTSK) uses NADCON method which is not supported by PROJ.
+-- UGKK (Slovak Geodetic and Cartographic Institute) provides also NTv2 grid file in addition
+-- to NADCON .las/.los files, so we define the NTv2 file here as an alternative.
+-- The file is available online but it does not have a confirmed open license yet,
+-- so it is not available in proj-datumgrid-europe for now
+('Slovakia_JTSK03_to_JTSK.LAS', 'Slovakia_JTSK03_to_JTSK.gsb', 'Slovakia_JTSK03_to_JTSK.gsb', 'NTv2', 'hgridshift', 0, NULL, 'https://www.geoportal.sk/files/gz/slovakia_jtsk03_to_jtsk_ntv2.zip', 0, 0, NULL),
 -- Superseded entries
 ('bluff-1955-to-nzvd2016-conversion.csv','nz_linz_blufht1955-nzvd2016.tif','blufht1955-nzvd2016.gtx','GTiff','vgridshift',0,NULL,'https://cdn.proj.org/nz_linz_blufht1955-nzvd2016.tif',1,1,NULL),
 ('dunedin-1958-to-nzvd2016-conversion.csv','nz_linz_duneht1958-nzvd2016.tif','duneht1958-nzvd2016.gtx','GTiff','vgridshift',0,NULL,'https://cdn.proj.org/nz_linz_duneht1958-nzvd2016.tif',1,1,NULL),
-- 
cgit v1.2.3

