Merge pull request #2222 from joto/geom-get-bbox

Add get_bbox() function to geometries in Lua

Author: lonvia

src/flex-lua-geom.cpp

@@ -8,6 +8,7 @@
  */
 
 #include "flex-lua-geom.hpp"
+#include "geom-box.hpp"
 #include "geom-functions.hpp"
 #include "geom-pole-of-inaccessibility.hpp"
 #include "lua-utils.hpp"
@@ -242,6 +243,23 @@ int geom_simplify(lua_State *lua_state)
     return 1;
 }
 
+int geom_get_bbox(lua_State *lua_state)
+{
+    auto const *const input_geometry = unpack_geometry(lua_state);
+
+    try {
+        auto const box = geom::envelope(*input_geometry);
+        lua_pushnumber(lua_state, box.min_x());
+        lua_pushnumber(lua_state, box.min_y());
+        lua_pushnumber(lua_state, box.max_x());
+        lua_pushnumber(lua_state, box.max_y());
+    } catch (...) {
+        return luaL_error(lua_state, "Unknown error in 'get_bbox()'.\n");
+    }
+
+    return 4;
+}
+
 int geom_srid(lua_State *lua_state)
 {
     auto const *const input_geometry = unpack_geometry(lua_state);
@@ -298,6 +316,7 @@ void init_geometry_class(lua_State *lua_state)
     luaX_add_table_func(lua_state, "area", geom_area);
     luaX_add_table_func(lua_state, "length", geom_length);
     luaX_add_table_func(lua_state, "centroid", geom_centroid);
+    luaX_add_table_func(lua_state, "get_bbox", geom_get_bbox);
     luaX_add_table_func(lua_state, "geometry_n", geom_geometry_n);
     luaX_add_table_func(lua_state, "geometry_type", geom_geometry_type);
     luaX_add_table_func(lua_state, "is_null", geom_is_null);

tests/bdd/flex/bbox.feature

@@ -18,6 +18,11 @@ Feature: Test get_bbox() function
             function osm2pgsql.process_node(object)
                 local row = { geom = object:as_point() }
                 row.min_x, row.min_y, row.max_x, row.max_y = object:get_bbox()
+                local min_x, min_y, max_x, max_y = object:as_point():get_bbox()
+                assert(row.min_x == min_x)
+                assert(row.min_y == min_y)
+                assert(row.max_x == max_x)
+                assert(row.max_y == max_y)
                 points:insert(row)
             end
             """
@@ -53,6 +58,11 @@ Feature: Test get_bbox() function
             function osm2pgsql.process_way(object)
                 local row = { geom = object:as_linestring() }
                 row.min_x, row.min_y, row.max_x, row.max_y = object:get_bbox()
+                local min_x, min_y, max_x, max_y = object:as_linestring():get_bbox()
+                assert(row.min_x == min_x)
+                assert(row.min_y == min_y)
+                assert(row.max_x == max_x)
+                assert(row.max_y == max_y)
                 highways:insert(row)
             end
             """
@@ -93,6 +103,11 @@ Feature: Test get_bbox() function
                 row.min_x, row.min_y, row.max_x, row.max_y = object:get_bbox()
                 for sgeom in object:as_multilinestring():line_merge():geometries() do
                     row.geom = sgeom
+                    local min_x, min_y, max_x, max_y = sgeom:get_bbox()
+                    assert(row.min_x == min_x)
+                    assert(row.min_y == min_y)
+                    assert(row.max_x == max_x)
+                    assert(row.max_y == max_y)
                     rels:insert(row)
                 end
             end