初始提交: UE5.3项目基础框架

Plugins/CesiumForUnreal/Source/ThirdParty/include/CesiumGeospatial/BoundingRegionBuilder.h

@@ -0,0 +1,101 @@
+#pragma once
+
+#include "BoundingRegion.h"
+#include "GlobeRectangle.h"
+#include "Library.h"
+
+namespace CesiumGeospatial {
+
+/**
+ * @brief Helper class for creating a \ref BoundingRegion or \ref GlobeRectangle
+ * from a set of points.
+ */
+class CESIUMGEOSPATIAL_API BoundingRegionBuilder {
+public:
+  /**
+   * @brief Constructs a new instance, starting with an empty bounding region.
+   */
+  BoundingRegionBuilder() noexcept;
+
+  /**
+   * @brief Gets the final region from this builder.
+   *
+   * If no positions are added to this builder, the returned region's rectangle
+   * will be {@link GlobeRectangle::EMPTY}, its minimum height will be 1.0, and
+   * its maximum height will be -1.0 (the minimum will be greater than the
+   * maximum).
+   */
+  BoundingRegion
+  toRegion(const Ellipsoid& ellipsoid CESIUM_DEFAULT_ELLIPSOID) const;
+
+  /**
+   * @brief Gets the final globe rectangle from this builder.
+   *
+   * If no positions are added to this builder, the returned region's rectangle
+   * will be {@link GlobeRectangle::EMPTY}.
+   */
+  GlobeRectangle toGlobeRectangle() const;
+
+  /**
+   * @brief Sets the distance from the North or South pole, in radians, that is
+   * considered "too close" to rely on the longitude value.
+   *
+   * When a position given to {@link expandToIncludePosition} has a latitude closer than this value,
+   * the region will be updated to include the position's _latitude_, but the
+   * position's longitude will be ignored.
+   *
+   * @param tolerance The new tolerance.
+   */
+  void setPoleTolerance(double tolerance) noexcept;
+
+  /**
+   * @brief Gets the distance from the North or South pole, in radians, that is
+   * considered "too close" to rely on the longitude value.
+   *
+   * When a position given to {@link expandToIncludePosition} has a latitude closer than this value,
+   * the region will be updated to include the position's _latitude_, but the
+   * position's longitude will be ignored.
+   *
+   * @return The tolerance.
+   */
+  double getPoleTolerance() const noexcept;
+
+  /**
+   * @brief Expands the bounding region to include the given position.
+   *
+   * The region will be kept as small as possible.
+   *
+   * @param position The position to be included in the region.
+   * @returns True if the region was modified, or false if the region already
+   * contained the position.
+   */
+  bool expandToIncludePosition(const Cartographic& position);
+
+private:
+  /**
+   * @brief When a position's latitude is within this distance in radians from
+   * the North or South pole, its longitude should be considered unreliable and
+   * not used to expand the bounding region in that direction.
+   */
+  double _poleTolerance;
+  GlobeRectangle _rectangle;
+  double _minimumHeight;
+  double _maximumHeight;
+
+  /**
+   * @brief True if the region is empty (covers no space) in the longitude
+   * direction.
+   *
+   * We know the rectangle is empty in the latitude direction when South
+   * is greater than North. But due to wrapping at the anti-meridian, the West
+   * longitude may very well be greater than the East longitude. So this field
+   * explicitly tracks whether the region is empty in the longitude direction.
+   *
+   * It's possible for the longitude range to be empty while the latitude range
+   * is not when all of the points used to expand the region so far have been
+   * too close to the poles to reliably use to compute longitude.
+   */
+  bool _longitudeRangeIsEmpty;
+};
+
+} // namespace CesiumGeospatial