Add RobotPoseEstimator (#571)

RobotPoseEstimator can pick the most likely pose for the robot given a number of possible poses, using a number of different strategies. Examples are still WIP.

photon-lib/src/main/native/include/photonlib/RobotPoseEstimator.h

@@ -0,0 +1,97 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2022 PhotonVision
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#pragma once
+
+#include <map>
+#include <memory>
+#include <utility>
+#include <vector>
+
+#include <frc/geometry/Pose3d.h>
+#include <frc/geometry/Transform3d.h>
+
+#include "photonlib/PhotonCamera.h"
+
+namespace photonlib {
+enum PoseStrategy : int {
+  LOWEST_AMBIGUITY,
+  CLOSEST_TO_CAMERA_HEIGHT,
+  CLOSEST_TO_REFERENCE_POSE,
+  CLOSEST_TO_LAST_POSE,
+  AVERAGE_BEST_TARGETS
+};
+
+/**
+ * A managing class to determine how an estimated pose should be chosen.
+ */
+class RobotPoseEstimator {
+  using map_value_type =
+      std::pair<std::shared_ptr<PhotonCamera>, frc::Transform3d>;
+  using size_type = std::vector<map_value_type>::size_type;
+
+ public:
+  explicit RobotPoseEstimator(std::map<int, frc::Pose3d> aprilTags,
+                              PoseStrategy strategy,
+                              std::vector<map_value_type>);
+
+  std::pair<frc::Pose3d, units::millisecond_t> Update();
+
+  void SetPoseStrategy(PoseStrategy strategy);
+
+  inline void SetReferencePose(frc::Pose3d referencePose) {
+    this->referencePose = referencePose;
+  }
+
+  inline void SetLastPose(frc::Pose3d lastPose) { this->lastPose = lastPose; }
+
+  inline void SetCameras(
+      const std::vector<std::pair<std::shared_ptr<PhotonCamera>,
+                                  frc::Transform3d>>& cameras) {
+    this->cameras = cameras;
+  }
+
+  PoseStrategy GetPoseStrategy() const { return strategy; }
+
+  frc::Pose3d GetLastPose() const { return lastPose; }
+
+  frc::Pose3d GetReferencePose() const { return referencePose; }
+
+ private:
+  std::map<int, frc::Pose3d> aprilTags;
+  PoseStrategy strategy;
+  std::vector<map_value_type> cameras;
+  frc::Pose3d lastPose;
+  frc::Pose3d referencePose;
+
+  std::pair<frc::Pose3d, units::millisecond_t> LowestAmbiguityStrategy();
+
+  std::pair<frc::Pose3d, units::millisecond_t> ClosestToCameraHeightStrategy();
+
+  std::pair<frc::Pose3d, units::millisecond_t> ClosestToReferencePoseStrategy();
+
+  std::pair<frc::Pose3d, units::millisecond_t> AverageBestTargetsStrategy();
+};
+
+}  // namespace photonlib