From 665dc21283165c2efec23c9815238648607cd3eb Mon Sep 17 00:00:00 2001
From: vng <viktor.govako@gmail.com>
Date: Mon, 6 Jun 2011 22:05:26 +0300
Subject: [PATCH] GetRationForLevel, GetRectForLevel implementation.

---
 indexer/indexer_tests/indexer_tests.pro |  1 +
 indexer/indexer_tests/scales_test.cpp   | 19 +++++++++++++++++++
 indexer/scales.cpp                      | 21 +++++++++++++++++++++
 indexer/scales.hpp                      |  6 ++++--
 4 files changed, 45 insertions(+), 2 deletions(-)
 create mode 100644 indexer/indexer_tests/scales_test.cpp

diff --git a/indexer/indexer_tests/indexer_tests.pro b/indexer/indexer_tests/indexer_tests.pro
index b1db0227e9..253c046db1 100644
--- a/indexer/indexer_tests/indexer_tests.pro
+++ b/indexer/indexer_tests/indexer_tests.pro
@@ -32,3 +32,4 @@ SOURCES += \
     geometry_coding_test.cpp \
     triangles_tree_coding_test.cpp \
     feature_routine.cpp \
+	scales_test.cpp \
diff --git a/indexer/indexer_tests/scales_test.cpp b/indexer/indexer_tests/scales_test.cpp
new file mode 100644
index 0000000000..f070730973
--- /dev/null
+++ b/indexer/indexer_tests/scales_test.cpp
@@ -0,0 +1,19 @@
+#include "../../testing/testing.hpp"
+#include "../scales.hpp"
+
+
+using namespace scales;
+
+UNIT_TEST(ScaleLevel_Smoke)
+{
+  for (int level = 1; level < GetUpperScale(); ++level)
+  {
+    double const d = GetRationForLevel(level);
+    int test = GetScaleLevel(d);
+    TEST_EQUAL(level, test, ());
+
+    m2::RectD const r = GetRectForLevel(level, m2::PointD(0.0, 0.0), 2.0);
+    test = GetScaleLevel(r);
+    TEST_EQUAL(level, test, ());
+  }
+}
\ No newline at end of file
diff --git a/indexer/scales.cpp b/indexer/scales.cpp
index 978698663e..b4e08a1f66 100644
--- a/indexer/scales.cpp
+++ b/indexer/scales.cpp
@@ -41,6 +41,27 @@ namespace scales
     return GetScaleLevel((dx + dy) / 2.0);
   }
 
+  double GetRationForLevel(int level)
+  {
+    if (level < initial_level) level = initial_level;
+    return pow(2.0, level - initial_level);
+  }
+
+  m2::RectD GetRectForLevel(int level, m2::PointD const & center, double X2YRatio)
+  {
+    double const dy = 2.0*GetRationForLevel(level) / (1.0 + X2YRatio);
+    double const dx = X2YRatio * dy;
+    ASSERT_GREATER ( dy, 0.0, () );
+    ASSERT_GREATER ( dx, 0.0, () );
+
+    double const xL = (MercatorBounds::maxX - MercatorBounds::minX) / (2.0*dx);
+    double const yL = (MercatorBounds::maxY - MercatorBounds::minY) / (2.0*dy);
+    ASSERT_GREATER ( xL, 0.0, () );
+    ASSERT_GREATER ( yL, 0.0, () );
+
+    return m2::RectD(center.x - xL, center.y - yL, center.x + xL, center.y + yL);
+  }
+
   namespace
   {
     double GetEpsilonImpl(int level, int logEps)
diff --git a/indexer/scales.hpp b/indexer/scales.hpp
index 96c13e4d40..e09124ddbe 100644
--- a/indexer/scales.hpp
+++ b/indexer/scales.hpp
@@ -10,11 +10,13 @@ namespace scales
 
   double GetM2PFactor(int level);
   int GetScaleLevel(double ratio);
+  int GetScaleLevel(m2::RectD const & r);
+
   /// @return such ration, that GetScaleLevel(ration) == level
   double GetRationForLevel(int level);
-  int GetScaleLevel(m2::RectD const & r);
   /// @return such rect, that GetScaleLevel(rect) == level
-  m2::RectD GetRectForLevel(int level, m2::PointD const & center, double widthToHeightRatio);
+  m2::RectD GetRectForLevel(int level, m2::PointD const & center, double X2YRatio);
+
   double GetEpsilonForLevel(int level);
   double GetEpsilonForSimplify(int level);
   bool IsGoodForLevel(int level, m2::RectD const & r);