Allow specifying an alternative URL base location for acquiring DEM SRTM files.

Advanced configuration setting only in viking.ini.
No GUI method provided ATM, as it's unlikely this setting needs changing.

diff --git a/help/C/viking.xml b/help/C/viking.xml
index 4de9f4b9074e1b6404048644c2c94c39a7800102..159c19099548b9f2f663a8cec147a506bac1910d 100644 (file)
--- a/help/C/viking.xml
+++ b/help/C/viking.xml
@@ -3457,6 +3457,11 @@ Accept: */*
          <listitem>
            <para>maps_scale_smaller_zoom_first=true</para>
          </listitem>
+         <listitem>
+           <para>srtm_http_base_url=https://dds.cr.usgs.gov/srtm/version2_1/SRTM3</para>
+           <para>Allows using an alternative service for acquiring DEM SRTM files.
+           Note that the layout on the server needs to be split into Continent directories.</para>
+         </listitem>
          <listitem>
            <para>mapnik_buffer_size=128 (in pixels)</para>
          </listitem>

diff --git a/src/vikdemlayer.c b/src/vikdemlayer.c
index d554f673170ba6553fdf84b6d744bf3d6247328b..934a755964a5409c8e06a86a384cdcdb33be14bf 100644 (file)
--- a/src/vikdemlayer.c
+++ b/src/vikdemlayer.c
@@ -47,9 +47,11 @@
 #include "icons/icons.h"
 
 #define MAPS_CACHE_DIR maps_layer_default_dir()
-
 #define SRTM_CACHE_TEMPLATE "%ssrtm3-%s%s%c%02d%c%03d.hgt.zip"
+
 #define SRTM_HTTP_BASE_URL "https://dds.cr.usgs.gov/srtm/version2_1/SRTM3"
+static gchar *base_url = NULL;
+#define VIK_SETTINGS_SRTM_HTTP_BASE_URL "srtm_http_base_url"
 
 #ifdef VIK_CONFIG_DEM24K
 #define DEM24K_DOWNLOAD_SCRIPT "dem24k.pl"
@@ -259,6 +261,16 @@ struct _VikDEMLayer {
   GtkMenu *right_click_menu;
 };
 
+// NB Only performed once per program run
+static void vik_dem_class_init ( VikDEMLayerClass *klass )
+{
+  // Note if suppling your own base URL - the site must still follow the Continent directory layout
+  if ( ! a_settings_get_string ( VIK_SETTINGS_SRTM_HTTP_BASE_URL, &base_url ) ) {
+    // Otherwise use the default
+    base_url = g_strdup ( SRTM_HTTP_BASE_URL );
+  }
+}
+
 GType vik_dem_layer_get_type ()
 {
   static GType vdl_type = 0;
@@ -270,7 +282,7 @@ GType vik_dem_layer_get_type ()
       sizeof (VikDEMLayerClass),
       NULL, /* base_init */
       NULL, /* base_finalize */
-      NULL, /* class init */
+      (GClassInitFunc) vik_dem_class_init, /* class init */
       NULL, /* class_finalize */
       NULL, /* class_data */
       sizeof (VikDEMLayer),
@@ -949,7 +961,7 @@ static void srtm_dem_download_thread ( DEMDownloadParams *p, gpointer threaddata
   }
 
   gchar *src_url = g_strdup_printf("%s/%s/%c%02d%c%03d.hgt.zip",
-                SRTM_HTTP_BASE_URL,
+                base_url,
                 continent_dir,
                (intlat >= 0) ? 'N' : 'S',
                ABS(intlat),
@@ -1209,7 +1221,7 @@ static void dem_layer_file_info ( GtkWidget *widget, struct LatLon *ll )
   gchar *source = NULL;
   if ( continent_dir )
     source = g_strdup_printf ( "%s/%s/%c%02d%c%03d.hgt.zip",
-                               SRTM_HTTP_BASE_URL,
+                               base_url,
                                continent_dir,
                                (intlat >= 0) ? 'N' : 'S',
                                ABS(intlat),