feat(editor): heightmap terrain from the terrain model of GUGiK, fitted to the tracks of the scenery

- editorNmt: squares of 500 m of the NMT at 1 m from the WCS service of geoportal.gov.pl, as GeoTIFF, fetched in the
  background, kept in editor/cache/nmt and sampled in the coordinates of the scenery, placed as its orthophoto is
- the terrain panel's Terrain model section: Fit to the tracks moves the model up or down by the median of the
  differences to the formation of the tracks (Biała Podlaska, built at 0: -145.73 m, 0.28 m around it); Along the tracks
  and Around the camera make the chunks as the model comes in; each path gets its formation and slopes 1:1.5 as a modifier
  of the terrain, laid over each other into one corridor, bridges and tunnels keep the model; the orthophoto is turned
  on and laid onto the new ground
- the http client of the orthophoto in editorHttp, shared; fill_from_nearest in editormodeshared.h
- after the generator of Hirek (MaszynaTerrainGenerator): the WCS requests, the cache of squares, the corridor by envelopes
- self-tests nmtfit, nmtmake, nmtwait

application/editormodeshared.h

@@ -9,6 +9,9 @@ http://mozilla.org/MPL/2.0/.
 
 #pragma once
 
+#include <deque>
+#include <vector>
+
 #include "imgui/imgui.h"
 #include "utilities/translation.h"
 
@@ -19,3 +22,33 @@ inline void item_tooltip(char const *Text)
 	if (ImGui::IsItemHovered())
 		ImGui::SetTooltip("%s", STR_C(Text));
 }
+
+// grid points without a height (or another value) take the one of the nearest point which has it (by steps along the grid)
+template <typename Value_> inline void fill_from_nearest(std::vector<Value_> &Heights, std::vector<char> &Found, std::size_t const Side)
+{
+    std::deque<std::size_t> queue;
+    for (std::size_t index = 0; index < Found.size(); ++index)
+        if (Found[index] != 0)
+            queue.push_back(index);
+    while (false == queue.empty())
+    {
+        auto const index = queue.front();
+        queue.pop_front();
+        auto const ix = index % Side, iz = index / Side;
+        auto const visit = [&](std::size_t const Next) {
+            if (Found[Next] != 0)
+                return;
+            Found[Next] = 1;
+            Heights[Next] = Heights[index];
+            queue.push_back(Next);
+        };
+        if (ix > 0)
+            visit(index - 1);
+        if (ix + 1 < Side)
+            visit(index + 1);
+        if (iz > 0)
+            visit(index - Side);
+        if (iz + 1 < Side)
+            visit(index + Side);
+    }
+}