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#pragma once
#include <mbgl/map/transform_state.hpp>
#include <mbgl/math/clamp.hpp>
#include <mbgl/tile/geometry_tile_data.hpp>
#include <mbgl/tile/tile_id.hpp>
#include <mbgl/util/geometry.hpp>
#include <mbgl/util/projection.hpp>
namespace mbgl {
using TileCoordinatePoint = Point<double>;
// Has floating point x/y coordinates.
// Used for computing the tiles that need to be visible in the viewport.
class TileCoordinate {
public:
TileCoordinatePoint p;
double z;
static TileCoordinate fromLatLng(double zoom, const LatLng& latLng) {
const double scale = std::pow(2.0, zoom);
return { Projection::project(latLng, scale) / double(util::tileSize), zoom };
}
static TileCoordinate fromScreenCoordinate(const TransformState& state, double zoom, const ScreenCoordinate& screenCoordinate) {
return fromLatLng(zoom, state.screenCoordinateToLatLng(screenCoordinate));
}
TileCoordinate zoomTo(double zoom) const {
const double scaleDiff = std::pow(2.0, zoom - z);
return { p * scaleDiff, zoom };
}
static GeometryCoordinate toGeometryCoordinate(const UnwrappedTileID& tileID, const TileCoordinatePoint& point) {
const double scale = std::pow(2.0, tileID.canonical.z);
auto zoomed = TileCoordinate { point, 0 }.zoomTo(tileID.canonical.z);
return {
int16_t(util::clamp<int64_t>((zoomed.p.x - tileID.canonical.x - tileID.wrap * scale) * util::EXTENT,
std::numeric_limits<int16_t>::min(),
std::numeric_limits<int16_t>::max())),
int16_t(util::clamp<int64_t>((zoomed.p.y - tileID.canonical.y) * util::EXTENT,
std::numeric_limits<int16_t>::min(),
std::numeric_limits<int16_t>::max()))
};
}
};
} // namespace mbgl
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