Add Photonlib (#231)

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

photonlib-cpp-examples/src/main/cpp/examples/aimandrange/cpp/Robot.cpp

@@ -0,0 +1,64 @@
+/**
+ * Copyright (C) 2018-2020 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/>.
+ */
+
+#include "Robot.h"
+
+#include <photonlib/PhotonUtils.h>
+
+void Robot::TeleopPeriodic() {
+  double forwardSpeed;
+  double rotationSpeed;
+
+  if (xboxController.GetAButton()) {
+    // Vision-alignment mode
+    // Query the latest result from PhotonVision
+    const auto &result = camera.GetLatestResult();
+
+    if (result.HasTargets()) {
+      // First calculate range
+      units::meter_t range =
+          photonlib::PhotonUtils::CalculateDistanceToTarget(
+              CAMERA_HEIGHT, TARGET_HEIGHT, CAMERA_PITCH,
+              units::degree_t{result.GetBestTarget().GetPitch()});
+
+      // Use this range as the measurement we give to the PID controller.
+      forwardSpeed = forwardController.Calculate(
+          range.to<double>(), GOAL_RANGE_METERS.to<double>());
+
+      // Also calculate angular power
+      rotationSpeed =
+          turnController.Calculate(result.GetBestTarget().GetYaw(), 0);
+    } else {
+      // If we have no targets, stay still.
+      forwardSpeed = 0;
+      rotationSpeed = 0;
+    }
+  } else {
+    // Manual Driver Mode
+    forwardSpeed =
+        xboxController.GetY(frc::GenericHID::JoystickHand::kRightHand);
+    rotationSpeed =
+        xboxController.GetX(frc::GenericHID::JoystickHand::kLeftHand);
+  }
+
+  // Use our forward/turn speeds to control the drivetrain
+  drive.ArcadeDrive(forwardSpeed, rotationSpeed);
+}
+
+#ifndef RUNNING_FRC_TESTS
+int main() { return frc::StartRobot<Robot>(); }
+#endif

photonlib-cpp-examples/src/main/cpp/examples/aimandrange/include/Robot.h

@@ -0,0 +1,64 @@
+/**
+ * Copyright (C) 2018-2020 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 <photonlib/PhotonCamera.h>
+
+#include <frc/PWMVictorSPX.h>
+#include <frc/TimedRobot.h>
+#include <frc/XboxController.h>
+#include <frc/controller/PIDController.h>
+#include <frc/drive/DifferentialDrive.h>
+#include <units/angle.h>
+#include <units/length.h>
+
+class Robot : public frc::TimedRobot {
+public:
+  void TeleopPeriodic() override;
+
+private:
+  // Constants such as camera and target height stored. Change per robot and
+  // goal!
+  const units::meter_t CAMERA_HEIGHT = 24_in;
+  const units::meter_t TARGET_HEIGHT = 5_ft;
+
+  // Angle between horizontal and the camera.
+  const units::radian_t CAMERA_PITCH = 0_deg;
+
+  // How far from the target we want to be
+  const units::meter_t GOAL_RANGE_METERS = 3_ft;
+
+  // PID constants should be tuned per robot
+  const double LINEAR_P = 0.1;
+  const double LINEAR_D = 0.0;
+  frc2::PIDController forwardController{LINEAR_P, 0.0, LINEAR_D};
+
+  const double ANGULAR_P = 0.1;
+  const double ANGULAR_D = 0.0;
+  frc2::PIDController turnController{ANGULAR_P, 0.0, ANGULAR_D};
+
+  // Change this to match the name of your camera
+  photonlib::PhotonCamera camera{"photonvision"};
+
+  frc::XboxController xboxController{0};
+
+  // Drive motors
+  frc::PWMVictorSPX leftMotor{0};
+  frc::PWMVictorSPX rightMotor{1};
+  frc::DifferentialDrive drive{leftMotor, rightMotor};
+};

photonlib-cpp-examples/src/main/cpp/examples/aimattarget/cpp/Robot.cpp

@@ -0,0 +1,51 @@
+/**
+ * Copyright (C) 2018-2020 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/>.
+ */
+
+#include "Robot.h"
+
+#include <photonlib/PhotonUtils.h>
+
+void Robot::TeleopPeriodic() {
+  double forwardSpeed =
+      xboxController.GetY(frc::GenericHID::JoystickHand::kRightHand);
+  double rotationSpeed;
+
+  if (xboxController.GetAButton()) {
+    // Vision-alignment mode
+    // Query the latest result from PhotonVision
+    photonlib::PhotonPipelineResult result = camera.GetLatestResult();
+
+    if (result.HasTargets()) {
+      // Rotation speed is the output of the PID controller
+      rotationSpeed = controller.Calculate(result.GetBestTarget().GetYaw(), 0);
+    } else {
+      // If we have no targets, stay still.
+      rotationSpeed = 0;
+    }
+  } else {
+    // Manual Driver Mode
+    rotationSpeed =
+        xboxController.GetX(frc::GenericHID::JoystickHand::kLeftHand);
+  }
+
+  // Use our forward/turn speeds to control the drivetrain
+  drive.ArcadeDrive(forwardSpeed, rotationSpeed);
+}
+
+#ifndef RUNNING_FRC_TESTS
+int main() { return frc::StartRobot<Robot>(); }
+#endif

photonlib-cpp-examples/src/main/cpp/examples/aimattarget/include/Robot.h

@@ -0,0 +1,46 @@
+/**
+ * Copyright (C) 2018-2020 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 <photonlib/PhotonCamera.h>
+
+#include <frc/PWMVictorSPX.h>
+#include <frc/TimedRobot.h>
+#include <frc/XboxController.h>
+#include <frc/controller/PIDController.h>
+#include <frc/drive/DifferentialDrive.h>
+#include <units/angle.h>
+#include <units/length.h>
+
+class Robot : public frc::TimedRobot {
+public:
+  void TeleopPeriodic() override;
+
+private:
+  // Change this to match the name of your camera
+  photonlib::PhotonCamera camera{"photonvision"};
+  // PID constants should be tuned per robot
+  frc2::PIDController controller{.1, 0, 0};
+
+  frc::XboxController xboxController{0};
+
+  // Drive motors
+  frc::PWMVictorSPX leftMotor{0};
+  frc::PWMVictorSPX rightMotor{1};
+  frc::DifferentialDrive drive{leftMotor, rightMotor};
+};

photonlib-cpp-examples/src/main/cpp/examples/examples.json

@@ -0,0 +1,38 @@
+[
+  {
+    "name": "AimAtTarget",
+    "description": "Aim at a target",
+    "tags": [],
+    "gradlebase": "cpp",
+    "language": "cpp",
+    "commandversion": 1,
+    "mainclass": "Main",
+    "packagetoreplace": null,
+    "dependencies": [],
+    "foldername": "aimattarget"
+  },
+  {
+    "name": "GetInRange",
+    "description": "Get in range of a target",
+    "tags": [],
+    "gradlebase": "cpp",
+    "language": "cpp",
+    "commandversion": 1,
+    "mainclass": "Main",
+    "packagetoreplace": null,
+    "dependencies": [],
+    "foldername": "getinrange"
+  },
+  {
+    "name": "AimAndRange",
+    "description": "Aim at a target while at a desired range",
+    "tags": [],
+    "gradlebase": "cpp",
+    "language": "cpp",
+    "commandversion": 1,
+    "mainclass": "Main",
+    "packagetoreplace": null,
+    "dependencies": [],
+    "foldername": "aimandrange"
+  }
+]

photonlib-cpp-examples/src/main/cpp/examples/getinrange/cpp/Robot.cpp

@@ -0,0 +1,57 @@
+/**
+ * Copyright (C) 2018-2020 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/>.
+ */
+
+#include "Robot.h"
+
+#include <photonlib/PhotonUtils.h>
+
+void Robot::TeleopPeriodic() {
+  double forwardSpeed;
+  double rotationSpeed =
+      xboxController.GetX(frc::GenericHID::JoystickHand::kLeftHand);
+
+  if (xboxController.GetAButton()) {
+    // Vision-alignment mode
+    // Query the latest result from PhotonVision
+    photonlib::PhotonPipelineResult result = camera.GetLatestResult();
+
+    if (result.HasTargets()) {
+      // First calculate range
+      units::meter_t range = photonlib::PhotonUtils::CalculateDistanceToTarget(
+          CAMERA_HEIGHT, TARGET_HEIGHT, CAMERA_PITCH,
+          units::degree_t{result.GetBestTarget().GetPitch()});
+
+      // Use this range as the measurement we give to the PID controller.
+      forwardSpeed = controller.Calculate(range.to<double>(),
+                                          GOAL_RANGE_METERS.to<double>());
+    } else {
+      // If we have no targets, stay still.
+      forwardSpeed = 0;
+    }
+  } else {
+    // Manual Driver Mode
+    forwardSpeed =
+        xboxController.GetY(frc::GenericHID::JoystickHand::kRightHand);
+  }
+
+  // Use our forward/turn speeds to control the drivetrain
+  drive.ArcadeDrive(forwardSpeed, rotationSpeed);
+}
+
+#ifndef RUNNING_FRC_TESTS
+int main() { return frc::StartRobot<Robot>(); }
+#endif

photonlib-cpp-examples/src/main/cpp/examples/getinrange/include/Robot.h

@@ -0,0 +1,60 @@
+/**
+ * Copyright (C) 2018-2020 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 <photonlib/PhotonCamera.h>
+
+#include <frc/PWMVictorSPX.h>
+#include <frc/TimedRobot.h>
+#include <frc/XboxController.h>
+#include <frc/controller/PIDController.h>
+#include <frc/drive/DifferentialDrive.h>
+#include <units/angle.h>
+#include <units/length.h>
+
+class Robot : public frc::TimedRobot {
+public:
+  void TeleopPeriodic() override;
+
+private:
+  // Constants such as camera and target height stored. Change per robot and
+  // goal!
+  const units::meter_t CAMERA_HEIGHT = 24_in;
+  const units::meter_t TARGET_HEIGHT = 5_ft;
+
+  // Angle between horizontal and the camera.
+  const units::radian_t CAMERA_PITCH = 0_deg;
+
+  // How far from the target we want to be
+  const units::meter_t GOAL_RANGE_METERS = 3_ft;
+
+  // PID constants should be tuned per robot
+  const double P_GAIN = 0.1;
+  const double D_GAIN = 0.0;
+  frc2::PIDController controller{P_GAIN, 0.0, D_GAIN};
+
+  // Change this to match the name of your camera
+  photonlib::PhotonCamera camera{"photonvision"};
+
+  frc::XboxController xboxController{0};
+
+  // Drive motors
+  frc::PWMVictorSPX leftMotor{0};
+  frc::PWMVictorSPX rightMotor{1};
+  frc::DifferentialDrive drive{leftMotor, rightMotor};
+};