Add Photonlib (#231)

Merges Photonlib into Photonvision, along with the Photonlib code examples. Also creates a new PhotonTargeting library teams can depend on.

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

@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) Photon Vision.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#pragma once
+
+#include <string>
+#include <vector>
+
+#include <frc/geometry/Translation2d.h>
+#include <units/angle.h>
+#include <units/area.h>
+#include <units/length.h>
+#include <units/time.h>
+#include <wpi/ArrayRef.h>
+#include <wpi/SmallVector.h>
+
+#include "photonlib/SimPhotonCamera.h"
+#include "photonlib/SimVisionTarget.h"
+
+namespace photonlib {
+
+/**
+ * Represents a camera that is connected to PhotonVision.
+ */
+class SimVisionSystem {
+ public:
+  explicit SimVisionSystem(const std::string& name, units::degree_t camDiagFOV,
+                           units::degree_t camPitch,
+                           frc::Transform2d cameraToRobot,
+                           units::meter_t cameraHeightOffGround,
+                           units::meter_t maxLEDRange, int cameraResWidth,
+                           int cameraResHeight, double minTargetArea);
+
+  void AddSimVisionTarget(SimVisionTarget tgt);
+  void MoveCamera(frc::Transform2d newcameraToRobot,
+                  units::meter_t newCamHeight, units::degree_t newCamPitch);
+  void ProcessFrame(frc::Pose2d robotPose);
+
+ private:
+  units::degree_t camDiagFOV;
+  units::degree_t camPitch;
+  frc::Transform2d cameraToRobot;
+  units::meter_t cameraHeightOffGround;
+  units::meter_t maxLEDRange;
+  int cameraResWidth;
+  int cameraResHeight;
+  double minTargetArea;
+  units::degree_t camHorizFOV;
+  units::degree_t camVertFOV;
+  std::vector<SimVisionTarget> tgtList = {};
+
+  double GetM2PerPx(units::meter_t dist);
+  bool CamCanSeeTarget(units::meter_t distHypot, units::degree_t yaw,
+                       units::degree_t pitch, double area);
+
+ public:
+  SimPhotonCamera cam = photonlib::SimPhotonCamera("Default");
+};
+
+}  // namespace photonlib