Merge remote-tracking branch 'upstream/pull/3016'

diff --git a/lib/osm.rb b/lib/osm.rb
index 51e98f4aea86add9b98eb464afcc2e79646c9cf9..b6dd64b9986131b04fb6ddf6a1e9043f073a9240 100644 (file)
--- a/lib/osm.rb
+++ b/lib/osm.rb
@@ -371,12 +371,17 @@ module OSM
     end
 
     # and these two will give you the right points on your image. all the constants can be reduced to speed things up. FIXME
+    # If the bbox has no extent, return the centre of the image to avoid dividing by zero.
 
     def y(lat)
+      return @height / 2 if (@by - @ty).zero?
+
       @height - ((ysheet(lat) - @ty) / (@by - @ty) * @height)
     end
 
     def x(lon)
+      return @width / 2 if (@bx - @tx).zero?
+
       ((xsheet(lon) - @tx) / (@bx - @tx) * @width)
     end
   end

diff --git a/test/lib/osm_test.rb b/test/lib/osm_test.rb
new file mode 100644 (file)
index 0000000..032ece5
--- /dev/null
+++ b/test/lib/osm_test.rb
@@ -0,0 +1,15 @@
+require "test_helper"
+
+class OsmTest < ActiveSupport::TestCase
+  def test_mercator
+    proj = OSM::Mercator.new(0, 0, 1, 1, 100, 200)
+    assert_in_delta(50, proj.x(0.5), 0.01)
+    assert_in_delta(100, proj.y(0.5), 0.01)
+  end
+
+  def test_mercator_collapsed_bbox
+    proj = OSM::Mercator.new(0, 0, 0, 0, 100, 200)
+    assert_in_delta(50, proj.x(0), 0.01)
+    assert_in_delta(100, proj.y(0), 0.01)
+  end
+end