lob.h

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// Copyright (c) 2025  Joel Benway
// SPDX-License-Identifier: GPL-3.0-or-later
// Please see end of file for extended copyright information
 
#ifndef LOB_H
#define LOB_H
 
#include <stddef.h>
#include <stdint.h>
 
#include "lob/lob_export.hpp"
 
#ifdef __cplusplus
extern "C" {
// NOLINTBEGIN
#endif

#define LOB_SPLINE_SEGMENTS 15
#define LOB_BUILDER_BUFFER_SIZE 320
#define LOB_WIND_POINTS 8

typedef uint8_t LobDragFunctionT;
enum {
  kLobDragFunctionG1 = 1,  
  kLobDragFunctionG2 = 2,  
  kLobDragFunctionG5 = 5,  
  kLobDragFunctionG6 = 6,  
  kLobDragFunctionG7 = 7,  
  kLobDragFunctionG8 = 8   
};

typedef uint8_t LobAtmosphereReferenceT;
enum {
  kLobAtmosphereReferenceArmyStandardMetro = 0,  
  kLobAtmosphereReferenceIcao =
      1  
};

typedef uint8_t LobClockAngleT;
enum {
  kLobClockAngleI = 1,     
  kLobClockAngleII = 2,    
  kLobClockAngleIII = 3,   
  kLobClockAngleIV = 4,    
  kLobClockAngleV = 5,     
  kLobClockAngleVI = 6,    
  kLobClockAngleVII = 7,   
  kLobClockAngleVIII = 8,  
  kLobClockAngleIX = 9,    
  kLobClockAngleX = 10,    
  kLobClockAngleXI = 11,   
  kLobClockAngleXII = 12   
};

typedef uint8_t LobErrorT;
enum {
  kLobErrorNone = 0,
  kLobErrorAirPressureOOR,
  kLobErrorAltitudeOfBarometerOOR,
  kLobErrorAltitudeOfFiringSiteOOR,
  kLobErrorAltitudeOfThermometerOOR,
  kLobErrorAzimuthOOR,
  kLobErrorBallisticCoefficientOOR,
  kLobErrorBallisticCoefficientRequired,
  kLobErrorBaseDiameterOOR,
  kLobErrorBcBandsInvalid,
  kLobErrorBcBandsNotMonotonic,
  kLobErrorBcBandsTooShort,
  kLobErrorDiameterOOR,
  kLobErrorHumidityOOR,
  kLobErrorInitialVelocityRequired,
  kLobErrorInternalError,
  kLobErrorLatitudeOOR,
  kLobErrorLengthOOR,
  kLobErrorMachDragTableInvalid,
  kLobErrorMachDragTableNotMonotonic,
  kLobErrorMachDragTableTooShort,
  kLobErrorMassOOR,
  kLobErrorMaximumTimeOOR,
  kLobErrorMeplatDiameterOOR,
  kLobErrorNoseLengthOOR,
  kLobErrorNotFormed,
  kLobErrorOgiveRtROOR,
  kLobErrorRangeAngleOOR,
  kLobErrorSplineCoefsInvalid,
  kLobErrorTailLengthOOR,
  kLobErrorWindHeadingOOR,
  kLobErrorWindProfileInvalid,
  kLobErrorWindProfileNotMonotonic,
  kLobErrorWindProfileTooLong,
  kLobErrorZeroAngleOOR,
  kLobErrorZeroDataRequired,
  kLobErrorZeroDistanceOOR,
  kLobErrorZeroUnreachable,
  kLobErrorNumberOfErrors  
};

typedef struct {
  double x;  
  double y;  
} LobGravity;

typedef struct {
  double range_ft;  
  double heading_deg;  
  double speed_mph;  
  double height_ft;  
} LobWindPoint;

typedef struct {
  uint32_t range_ft;  
  double x_fps;  
  double y_fps;  
  double z_fps;  
} LobWindNode;

typedef struct {
  double cos_l_sin_a;  
  double sin_l;        
  double cos_l_cos_a;  
} LobCoriolis;

typedef struct {
  double drag_coeff;        
  double speed_of_sound;    
  double mass;              
  double optic_height;      
  LobGravity gravity;       
  LobCoriolis coriolis;     
  double zero_angle;        
  double stability_factor;  
  double aerodynamic_jump;  
  double spindrift_factor;  
  double k_lapse;           
  double max_time;          
  float drags[LOB_SPLINE_SEGMENTS * 4];  
  LobWindNode wind_nodes[LOB_WIND_POINTS];  
  double wind_shear_exponent;  
  uint16_t velocity;       
  uint16_t minimum_speed;  
  uint16_t step_size;      
  LobErrorT error;         
  uint8_t wind_count;      
} LobContext;

typedef struct {
  uint32_t range;     
  uint16_t velocity;  
  uint32_t energy;    
  double elevation;   
  double
      deflection;  
  double time_of_flight;  
} LobOutput;

typedef struct {
  union {
    double align_double;
    size_t align_size;
    uint8_t buffer[LOB_BUILDER_BUFFER_SIZE];
  } buffer;
} LobBuilder;

LOB_EXPORT extern const char* LobVersion(void);

LOB_EXPORT extern void LobBuilderInit(LobBuilder* pbuilder);
LOB_EXPORT extern void LobBuilderDestroy(LobBuilder* pbuilder);
LOB_EXPORT extern void LobBuilderCopy(LobBuilder* dst, const LobBuilder* src);
LOB_EXPORT extern LobBuilder* LobBuilderReset(LobBuilder* pbuilder);

LOB_EXPORT extern LobBuilder* LobBuilderBallisticCoefficientPsi(
    LobBuilder* pbuilder, double value);

LOB_EXPORT extern LobBuilder* LobBuilderBCAtmosphere(
    LobBuilder* pbuilder, LobAtmosphereReferenceT type);

LOB_EXPORT extern LobBuilder* LobBuilderBCDragFunction(LobBuilder* pbuilder,
                                                       LobDragFunctionT type);

LOB_EXPORT extern LobBuilder* LobBuilderDiameterInch(LobBuilder* pbuilder,
                                                     double value);

LOB_EXPORT extern LobBuilder* LobBuilderMeplatDiameterInch(LobBuilder* pbuilder,
                                                           double value);

LOB_EXPORT extern LobBuilder* LobBuilderBaseDiameterInch(LobBuilder* pbuilder,
                                                         double value);

LOB_EXPORT extern LobBuilder* LobBuilderLengthInch(LobBuilder* pbuilder,
                                                   double value);

LOB_EXPORT extern LobBuilder* LobBuilderNoseLengthInch(LobBuilder* pbuilder,
                                                       double value);

LOB_EXPORT extern LobBuilder* LobBuilderTailLengthInch(LobBuilder* pbuilder,
                                                       double value);

LOB_EXPORT extern LobBuilder* LobBuilderOgiveRtR(LobBuilder* pbuilder,
                                                 double value);

LOB_EXPORT extern LobBuilder* LobBuilderSplineFitTable(LobBuilder* pbuilder,
                                                       const float* pmachs,
                                                       const float* pdrags,
                                                       size_t size);

LOB_EXPORT extern LobBuilder* LobBuilderBCVelocityBands(LobBuilder* pbuilder,
                                                        const float* pfps,
                                                        const float* pbcs,
                                                        size_t size);

LOB_EXPORT extern LobBuilder* LobBuilderSplineCoefficients(LobBuilder* pbuilder,
                                                           const float* pcoefs);

LOB_EXPORT extern LobBuilder* LobBuilderMassGrains(LobBuilder* pbuilder,
                                                   double value);

LOB_EXPORT extern LobBuilder* LobBuilderInitialVelocityFps(LobBuilder* pbuilder,
                                                           uint16_t value);

LOB_EXPORT extern LobBuilder* LobBuilderOpticHeightInches(LobBuilder* pbuilder,
                                                          double value);

LOB_EXPORT extern LobBuilder* LobBuilderTwistInchesPerTurn(LobBuilder* pbuilder,
                                                           double value);

LOB_EXPORT extern LobBuilder* LobBuilderZeroAngleMOA(LobBuilder* pbuilder,
                                                     double value);

LOB_EXPORT extern LobBuilder* LobBuilderZeroDistanceYds(LobBuilder* pbuilder,
                                                        double value);

LOB_EXPORT extern LobBuilder* LobBuilderZeroImpactHeightInches(
    LobBuilder* pbuilder, double value);

LOB_EXPORT extern LobBuilder* LobBuilderAltitudeOfFiringSiteFt(
    LobBuilder* pbuilder, double value);

LOB_EXPORT extern LobBuilder* LobBuilderAirPressureInHg(LobBuilder* pbuilder,
                                                        double value);

LOB_EXPORT extern LobBuilder* LobBuilderAltitudeOfBarometerFt(
    LobBuilder* pbuilder, double value);

LOB_EXPORT extern LobBuilder* LobBuilderTemperatureDegF(LobBuilder* pbuilder,
                                                        double value);

LOB_EXPORT extern LobBuilder* LobBuilderAltitudeOfThermometerFt(
    LobBuilder* pbuilder, double value);

LOB_EXPORT extern LobBuilder* LobBuilderRelativeHumidityPercent(
    LobBuilder* pbuilder, double value);

LOB_EXPORT extern LobBuilder* LobBuilderWindHeading(LobBuilder* pbuilder,
                                                    LobClockAngleT value);

LOB_EXPORT extern LobBuilder* LobBuilderWindHeadingDeg(LobBuilder* pbuilder,
                                                       double value);

LOB_EXPORT extern LobBuilder* LobBuilderWindSpeedFps(LobBuilder* pbuilder,
                                                     double value);

LOB_EXPORT extern LobBuilder* LobBuilderWindSpeedMph(LobBuilder* pbuilder,
                                                     double value);

LOB_EXPORT extern LobBuilder* LobBuilderWindProfile(
    LobBuilder* pbuilder, const LobWindPoint* ppoints, size_t count);

LOB_EXPORT extern LobBuilder* LobBuilderWindShearExponent(
    LobBuilder* pbuilder, double value);

LOB_EXPORT extern LobBuilder* LobBuilderAzimuthDeg(LobBuilder* pbuilder,
                                                   double value);

LOB_EXPORT extern LobBuilder* LobBuilderLatitudeDeg(LobBuilder* pbuilder,
                                                    double value);

LOB_EXPORT extern LobBuilder* LobBuilderRangeAngleDeg(LobBuilder* pbuilder,
                                                      double value);

LOB_EXPORT extern LobBuilder* LobBuilderMinimumSpeed(LobBuilder* pbuilder,
                                                     uint16_t value);

LOB_EXPORT extern LobBuilder* LobBuilderMinimumEnergy(LobBuilder* pbuilder,
                                                      uint16_t value);

LOB_EXPORT extern LobBuilder* LobBuilderMaximumTime(LobBuilder* pbuilder,
                                                    double value);

LOB_EXPORT extern LobBuilder* LobBuilderStepSize(LobBuilder* pbuilder,
                                                 uint16_t value);

LOB_EXPORT extern void LobBuilderBuild(LobBuilder* pbuilder,
                                       LobContext* presult);

LOB_EXPORT extern size_t LobSolve(const LobContext* pctx,
                                  const uint32_t* pranges, LobOutput* pouts,
                                  size_t size);

LOB_EXPORT extern size_t LobFastInverse(const LobContext* pctx,
                                        LobOutput* pouts, size_t size);

LOB_EXPORT extern size_t LobSolveInverse(const LobContext* pctx,
                                         const uint32_t* pranges,
                                         LobOutput* pouts, size_t size);

LOB_EXPORT extern double LobMoaToMil(double value);
LOB_EXPORT extern double LobMoaToDeg(double value);
LOB_EXPORT extern double LobMoaToIphy(double value);
LOB_EXPORT extern double LobMoaToInch(double value, double range_ft);

LOB_EXPORT extern double LobMilToMoa(double value);
LOB_EXPORT extern double LobMilToDeg(double value);
LOB_EXPORT extern double LobMilToIphy(double value);
LOB_EXPORT extern double LobMilToInch(double value, double range_ft);

LOB_EXPORT extern double LobDegToMoa(double value);
LOB_EXPORT extern double LobDegToMil(double value);

LOB_EXPORT extern double LobInchToMoa(double value, double range_ft);
LOB_EXPORT extern double LobInchToMil(double value, double range_ft);
LOB_EXPORT extern double LobInchToDeg(double value, double range_ft);

LOB_EXPORT extern double LobJToFtLbs(double value);
LOB_EXPORT extern double LobFtLbsToJ(double value);

LOB_EXPORT extern double LobMToYd(double value);
LOB_EXPORT extern double LobYdToFt(double value);
LOB_EXPORT extern double LobMToFt(double value);
LOB_EXPORT extern double LobFtToIn(double value);
LOB_EXPORT extern double LobMmToIn(double value);
LOB_EXPORT extern double LobCmToIn(double value);
LOB_EXPORT extern double LobYdToM(double value);
LOB_EXPORT extern double LobFtToM(double value);
LOB_EXPORT extern double LobFtToYd(double value);
LOB_EXPORT extern double LobInToMm(double value);
LOB_EXPORT extern double LobInToCm(double value);
LOB_EXPORT extern double LobInToFt(double value);

LOB_EXPORT extern double LobPaToInHg(double value);
LOB_EXPORT extern double LobMbarToInHg(double value);
LOB_EXPORT extern double LobPsiToInHg(double value);

LOB_EXPORT extern double LobLbsToGrain(double value);
LOB_EXPORT extern double LobGToGrain(double value);
LOB_EXPORT extern double LobKgToGrain(double value);

LOB_EXPORT extern double LobKgSqMToPmsi(double value);

LOB_EXPORT extern double LobFpsToMps(double value);
LOB_EXPORT extern double LobMpsToFps(double value);
LOB_EXPORT extern double LobKphToMph(double value);
LOB_EXPORT extern double LobKnToMph(double value);

LOB_EXPORT extern double LobMsToS(double value);
LOB_EXPORT extern double LobUsToS(double value);
LOB_EXPORT extern double LobSToMs(double value);
LOB_EXPORT extern double LobSToUs(double value);

LOB_EXPORT extern double LobDegCToDegF(double value);
 
#ifdef __cplusplus
// NOLINTEND
}
#endif
 
#endif  // LOB_H
 
// This file is part of lob.
//
// lob 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.
//
// lob 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
// lob. If not, see <https://www.gnu.org/licenses/>.