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#include "indexer/scales.hpp"
#include "geometry/mercator.hpp"
#include "base/math.hpp"
#include "std/algorithm.hpp"
namespace scales
{
static const int INITIAL_LEVEL = 1;
int GetMinAllowableIn3dScale()
{
return min(16, min(GetNavigation3dScale(), GetPedestrianNavigation3dScale()));
}
double GetScaleLevelD(double ratio)
{
double const level = min(static_cast<double>(GetUpperScale()), log(ratio) / log(2.0) + INITIAL_LEVEL);
return (level < 0.0 ? 0.0 : level);
}
double GetScaleLevelD(m2::RectD const & r)
{
// TODO: fix scale factors for mercator projection
double const dx = (MercatorBounds::maxX - MercatorBounds::minX) / r.SizeX();
double const dy = (MercatorBounds::maxY - MercatorBounds::minY) / r.SizeY();
// get the average ratio
return GetScaleLevelD((dx + dy) / 2.0);
}
int GetScaleLevel(double ratio)
{
return my::rounds(GetScaleLevelD(ratio));
}
int GetScaleLevel(m2::RectD const & r)
{
return my::rounds(GetScaleLevelD(r));
}
double GetRationForLevel(double level)
{
if (level < INITIAL_LEVEL)
level = INITIAL_LEVEL;
return pow(2.0, level - INITIAL_LEVEL);
}
m2::RectD GetRectForLevel(double level, m2::PointD const & center)
{
double const dy = GetRationForLevel(level);
double const dx = 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(MercatorBounds::ClampX(center.x - xL),
MercatorBounds::ClampY(center.y - yL),
MercatorBounds::ClampX(center.x + xL),
MercatorBounds::ClampY(center.y + yL));
}
namespace
{
double GetEpsilonImpl(long level, double pixelTolerance)
{
return (MercatorBounds::maxX - MercatorBounds::minX) * pixelTolerance / double(256L << level);
}
}
double GetEpsilonForLevel(int level)
{
return GetEpsilonImpl(level, 7);
}
double GetEpsilonForSimplify(int level)
{
// Keep better geometries on highest zoom to allow scaling them deeper
if (level == GetUpperScale())
return GetEpsilonImpl(level, 0.4);
// Keep crude geometries for all other zooms
else
return GetEpsilonImpl(level, 1.3);
}
bool IsGoodForLevel(int level, m2::RectD const & r)
{
// assume that feature is always visible in upper scale
return (level == GetUpperScale() || max(r.SizeX(), r.SizeY()) > GetEpsilonForLevel(level));
}
}
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