Restore accidentally removed files

gazebo/flix.h

@@ -0,0 +1,48 @@
+// Copyright (c) 2023 Oleg Kalachev <okalachev@gmail.com>
+// Repository: https://github.com/okalachev/flix
+
+// Declarations of some functions and variables in Arduino code
+
+#include <cmath>
+#include "vector.h"
+#include "quaternion.h"
+
+#define RC_CHANNELS 6
+
+#define MOTOR_REAR_LEFT 0
+#define MOTOR_FRONT_LEFT 3
+#define MOTOR_FRONT_RIGHT 2
+#define MOTOR_REAR_RIGHT 1
+
+uint32_t startTime;
+uint32_t stepTime;
+uint32_t steps;
+float stepsPerSecond;
+float dt;
+float motors[4];
+int16_t channels[16]; // raw rc channels WARNING: unsigned on hardware
+float controls[RC_CHANNELS];
+Vector acc;
+Vector rates;
+Quaternion attitude;
+
+// control
+void control();
+void interpretRC();
+static void controlAttitude();
+static void controlAttitudeAlter();
+static void controlManual();
+static void controlRate();
+void desaturate(float& a, float& b, float& c, float& d);
+static void indicateSaturation();
+
+// cli
+static void showTable();
+static void cliTestMotor(uint8_t n);
+
+// mocks
+void setLED(bool on) {};
+void calibrateGyro() {};
+void fullMotorTest(int n) {};
+void sendMotors() {};
+void printIMUCal() { Serial.print("N/A"); };