ACE3/extensions/advanced_ballistics/AdvancedBallistics.cpp
2018-01-17 03:36:10 -08:00

648 lines
29 KiB
C++

#include "shared.hpp"
#include <stdlib.h>
#include <string>
#include <vector>
#include <unordered_map>
#include <random>
#define GRAVITY 9.80665f
#define ABSOLUTE_ZERO_IN_CELSIUS -273.15f
#define KELVIN(t) (t - ABSOLUTE_ZERO_IN_CELSIUS)
#define CELSIUS(t) (t + ABSOLUTE_ZERO_IN_CELSIUS)
#define UNIVERSAL_GAS_CONSTANT 8.314f
#define WATER_VAPOR_MOLAR_MASS 0.018016f
#define DRY_AIR_MOLAR_MASS 0.028964f
#define SPECIFIC_GAS_CONSTANT_DRY_AIR 287.058f
#define STD_AIR_DENSITY_ICAO 1.22498f
#define STD_AIR_DENSITY_ASM 1.20885f
struct Bullet {
double airFriction;
double caliber;
double bulletLength;
double bulletMass;
std::vector<double> ballisticCoefficients;
std::vector<double> velocityBoundaries;
char* atmosphereModel;
int dragModel;
std::vector<double> muzzleVelocities;
std::vector<double> barrelLengths;
double stabilityFactor;
double twistDirection;
double transonicStabilityCoef;
double muzzleVelocity;
std::vector<double> origin;
double latitude;
double temperature;
double altitude;
double humidity;
double overcast;
double startTime;
double speed;
double frames;
double lastFrame;
double hDeflection;
double spinDrift;
unsigned randSeed;
std::default_random_engine randGenerator;
};
struct Map {
std::vector<int> gridHeights;
std::vector<int> gridBuildingNums;
std::vector<int> gridSurfaceIsWater;
int mapSize;
int mapGrids;
};
std::vector<Bullet> bulletDatabase;
std::unordered_map<std::string, Map> mapDatabase;
std::string worldName = "";
Map* map = &mapDatabase[""];
double calculateRoughnessLength(double posX, double posY) {
// Source: http://es.ucsc.edu/~jnoble/wind/extrap/index.html
double roughness_lengths[10] = {0.0002, 0.0005, 0.0024, 0.03, 0.055, 0.1, 0.2, 0.4, 0.8, 1.6};
double roughnessLength = 0.0024;
int gridX = (int)floor(posX / 50);
int gridY = (int)floor(posY / 50);
int gridCell = gridX * map->mapGrids + gridY;
if (gridCell >= 0 && (std::size_t)gridCell < map->gridHeights.size() && (std::size_t)gridCell < map->gridBuildingNums.size()) {
int nearBuildings = map->gridBuildingNums[gridCell];
int surfaceIsWater = map->gridSurfaceIsWater[gridCell];
if (nearBuildings == 0 && surfaceIsWater == 1) {
return 0.0005;
}
if (nearBuildings >= 10) {
return 1.6;
}
return roughness_lengths[2 + std::min(nearBuildings, 6)];
}
return 0.0024;
}
double calculateAirDensity(double temperature, double pressure, double relativeHumidity) {
pressure = pressure * 100;
if (relativeHumidity > 0) {
double _pSat = 6.1078 * pow(10, ((7.5 * temperature) / (temperature + 237.3)));
double vaporPressure = relativeHumidity * _pSat;
double partialPressure = pressure - vaporPressure;
return (partialPressure * DRY_AIR_MOLAR_MASS + vaporPressure * WATER_VAPOR_MOLAR_MASS) / (UNIVERSAL_GAS_CONSTANT * KELVIN(temperature));
} else {
return pressure / (SPECIFIC_GAS_CONSTANT_DRY_AIR * KELVIN(temperature));
}
}
double calculateAtmosphericCorrection(double ballisticCoefficient, double temperature, double pressure, double relativeHumidity, const char *atmosphereModel) {
double airDensity = calculateAirDensity(temperature, pressure, relativeHumidity);
if (!strcmp(atmosphereModel, "ICAO")) {
return (STD_AIR_DENSITY_ICAO / airDensity) * ballisticCoefficient;
} else {
return (STD_AIR_DENSITY_ASM / airDensity) * ballisticCoefficient;
}
}
double calculateRetard(int DragFunction, double DragCoefficient, double Velocity) {
double vel = Velocity * 3.2808399;
double val = -1;
double A = -1;
double M = -1;
switch (DragFunction) {
case 1:
if (vel> 4230) { A = 1.477404177730177e-04; M = 1.9565; }
else if (vel> 3680) { A = 1.920339268755614e-04; M = 1.925; }
else if (vel> 3450) { A = 2.894751026819746e-04; M = 1.875; }
else if (vel> 3295) { A = 4.349905111115636e-04; M = 1.825; }
else if (vel> 3130) { A = 6.520421871892662e-04; M = 1.775; }
else if (vel> 2960) { A = 9.748073694078696e-04; M = 1.725; }
else if (vel> 2830) { A = 1.453721560187286e-03; M = 1.675; }
else if (vel> 2680) { A = 2.162887202930376e-03; M = 1.625; }
else if (vel> 2460) { A = 3.209559783129881e-03; M = 1.575; }
else if (vel> 2225) { A = 3.904368218691249e-03; M = 1.55; }
else if (vel> 2015) { A = 3.222942271262336e-03; M = 1.575; }
else if (vel> 1890) { A = 2.203329542297809e-03; M = 1.625; }
else if (vel> 1810) { A = 1.511001028891904e-03; M = 1.675; }
else if (vel> 1730) { A = 8.609957592468259e-04; M = 1.75; }
else if (vel> 1595) { A = 4.086146797305117e-04; M = 1.85; }
else if (vel> 1520) { A = 1.954473210037398e-04; M = 1.95; }
else if (vel> 1420) { A = 5.431896266462351e-05; M = 2.125; }
else if (vel> 1360) { A = 8.847742581674416e-06; M = 2.375; }
else if (vel> 1315) { A = 1.456922328720298e-06; M = 2.625; }
else if (vel> 1280) { A = 2.419485191895565e-07; M = 2.875; }
else if (vel> 1220) { A = 1.657956321067612e-08; M = 3.25; }
else if (vel> 1185) { A = 4.745469537157371e-10; M = 3.75; }
else if (vel> 1150) { A = 1.379746590025088e-11; M = 4.25; }
else if (vel> 1100) { A = 4.070157961147882e-13; M = 4.75; }
else if (vel> 1060) { A = 2.938236954847331e-14; M = 5.125; }
else if (vel> 1025) { A = 1.228597370774746e-14; M = 5.25; }
else if (vel> 980) { A = 2.916938264100495e-14; M = 5.125; }
else if (vel> 945) { A = 3.855099424807451e-13; M = 4.75; }
else if (vel> 905) { A = 1.185097045689854e-11; M = 4.25; }
else if (vel> 860) { A = 3.566129470974951e-10; M = 3.75; }
else if (vel> 810) { A = 1.045513263966272e-08; M = 3.25; }
else if (vel> 780) { A = 1.291159200846216e-07; M = 2.875; }
else if (vel> 750) { A = 6.824429329105383e-07; M = 2.625; }
else if (vel> 700) { A = 3.569169672385163e-06; M = 2.375; }
else if (vel> 640) { A = 1.839015095899579e-05; M = 2.125; }
else if (vel> 600) { A = 5.71117468873424e-05; M = 1.950; }
else if (vel> 550) { A = 9.226557091973427e-05; M = 1.875; }
else if (vel> 250) { A = 9.337991957131389e-05; M = 1.875; }
else if (vel> 100) { A = 7.225247327590413e-05; M = 1.925; }
else if (vel> 65) { A = 5.792684957074546e-05; M = 1.975; }
else if (vel> 0) { A = 5.206214107320588e-05; M = 2.000; }
break;
case 2:
if (vel> 1674) { A = .0079470052136733; M = 1.36999902851493; }
else if (vel> 1172) { A = 1.00419763721974e-03; M = 1.65392237010294; }
else if (vel> 1060) { A = 7.15571228255369e-23; M = 7.91913562392361; }
else if (vel> 949) { A = 1.39589807205091e-10; M = 3.81439537623717; }
else if (vel> 670) { A = 2.34364342818625e-04; M = 1.71869536324748; }
else if (vel> 335) { A = 1.77962438921838e-04; M = 1.76877550388679; }
else if (vel> 0) { A = 5.18033561289704e-05; M = 1.98160270524632; }
break;
case 5:
if (vel> 1730) { A = 7.24854775171929e-03; M = 1.41538574492812; }
else if (vel> 1228) { A = 3.50563361516117e-05; M = 2.13077307854948; }
else if (vel> 1116) { A = 1.84029481181151e-13; M = 4.81927320350395; }
else if (vel> 1004) { A = 1.34713064017409e-22; M = 7.8100555281422; }
else if (vel> 837) { A = 1.03965974081168e-07; M = 2.84204791809926; }
else if (vel> 335) { A = 1.09301593869823e-04; M = 1.81096361579504; }
else if (vel> 0) { A = 3.51963178524273e-05; M = 2.00477856801111; }
break;
case 6:
if (vel> 3236) { A = 0.0455384883480781; M = 1.15997674041274; }
else if (vel> 2065) { A = 7.167261849653769e-02; M = 1.10704436538885; }
else if (vel> 1311) { A = 1.66676386084348e-03; M = 1.60085100195952; }
else if (vel> 1144) { A = 1.01482730119215e-07; M = 2.9569674731838; }
else if (vel> 1004) { A = 4.31542773103552e-18; M = 6.34106317069757; }
else if (vel> 670) { A = 2.04835650496866e-05; M = 2.11688446325998; }
else if (vel> 0) { A = 7.50912466084823e-05; M = 1.92031057847052; }
break;
case 7:
if (vel> 4200) { A = 1.29081656775919e-09; M = 3.24121295355962; }
else if (vel> 3000) { A = 0.0171422231434847; M = 1.27907168025204; }
else if (vel> 1470) { A = 2.33355948302505e-03; M = 1.52693913274526; }
else if (vel> 1260) { A = 7.97592111627665e-04; M = 1.67688974440324; }
else if (vel> 1110) { A = 5.71086414289273e-12; M = 4.3212826264889; }
else if (vel> 960) { A = 3.02865108244904e-17; M = 5.99074203776707; }
else if (vel> 670) { A = 7.52285155782535e-06; M = 2.1738019851075; }
else if (vel> 540) { A = 1.31766281225189e-05; M = 2.08774690257991; }
else if (vel> 0) { A = 1.34504843776525e-05; M = 2.08702306738884; }
break;
case 8:
if (vel> 3571) { A = .0112263766252305; M = 1.33207346655961; }
else if (vel> 1841) { A = .0167252613732636; M = 1.28662041261785; }
else if (vel> 1120) { A = 2.20172456619625e-03; M = 1.55636358091189; }
else if (vel> 1088) { A = 2.0538037167098e-16; M = 5.80410776994789; }
else if (vel> 976) { A = 5.92182174254121e-12; M = 4.29275576134191; }
else if (vel> 0) { A = 4.3917343795117e-05; M = 1.99978116283334; }
break;
default:
break;
}
if (A != -1 && M != -1 && vel > 0 && vel < 10000) {
val = A * pow(vel, M) / DragCoefficient;
val = val / 3.2808399;
return val;
}
return 0.0;
}
extern "C"
{
EXPORT void __stdcall RVExtension(char *output, int outputSize, const char *function);
}
void __stdcall RVExtension(char *output, int outputSize, const char *function)
{
ZERO_OUTPUT();
std::stringstream outputStr;
if (!strcmp(function, "version")) {
strncpy_s(output, outputSize, ACE_FULL_VERSION_STR, _TRUNCATE);
EXTENSION_RETURN();
}
char* input = _strdup(function);
char* token = NULL;
char* next_token = NULL;
char* mode = strtok_s(input, ":", &next_token);
if (!strcmp(mode, "retard")) {
double ballisticCoefficient = 1.0;
int dragModel = 1;
double velocity = 0.0;
double retard = 0.0;
dragModel = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
ballisticCoefficient = strtod(strtok_s(NULL, ":", &next_token), NULL);
velocity = strtod(strtok_s(NULL, ":", &next_token), NULL);
retard = calculateRetard(dragModel, ballisticCoefficient, velocity);
// int n = sprintf(output, "%f", retard);
outputStr << retard;
strncpy_s(output, outputSize, outputStr.str().c_str(), _TRUNCATE);
EXTENSION_RETURN();
} else if (!strcmp(mode, "atmosphericCorrection")) {
double ballisticCoefficient = 1.0;
double temperature = 15.0;
double pressure = 1013.25;
double humidity = 0.0;
char* atmosphereModel;
ballisticCoefficient = strtod(strtok_s(NULL, ":", &next_token), NULL);
temperature = strtod(strtok_s(NULL, ":", &next_token), NULL);
pressure = strtod(strtok_s(NULL, ":", &next_token), NULL);
humidity = strtod(strtok_s(NULL, ":", &next_token), NULL);
atmosphereModel = strtok_s(NULL, ":", &next_token);
ballisticCoefficient = calculateAtmosphericCorrection(ballisticCoefficient, temperature, pressure, humidity, atmosphereModel);
//int n = sprintf(output, "%f", ballisticCoefficient);
outputStr << ballisticCoefficient;
strncpy_s(output, outputSize, outputStr.str().c_str(), _TRUNCATE);
EXTENSION_RETURN();
} else if (!strcmp(mode, "new")) {
unsigned int index = 0;
double airFriction = 0.0;
char* ballisticCoefficientArray;
char* ballisticCoefficient;
std::vector<double> ballisticCoefficients;
char* velocityBoundaryArray;
char* velocityBoundary;
std::vector<double> velocityBoundaries;
char* atmosphereModel;
int dragModel = 1;
double stabilityFactor = 1.5;
int twistDirection = 1;
double transonicStabilityCoef = 1;
double muzzleVelocity = 850;
char* originArray;
char* originEntry;
std::vector<double> origin;
double latitude = 0.0;
double temperature = 0.0;
double altitude = 0.0;
double humidity = 0.0;
double overcast = 0.0;
double tickTime = 0.0;
index = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
airFriction = strtod(strtok_s(NULL, ":", &next_token), NULL);
ballisticCoefficientArray = strtok_s(NULL, ":", &next_token);
ballisticCoefficientArray++;
ballisticCoefficientArray[strlen(ballisticCoefficientArray) - 1] = 0;
ballisticCoefficient = strtok_s(ballisticCoefficientArray, ",", &token);
while (ballisticCoefficient != NULL) {
ballisticCoefficients.push_back(strtod(ballisticCoefficient, NULL));
ballisticCoefficient = strtok_s(NULL, ",", &token);
}
velocityBoundaryArray = strtok_s(NULL, ":", &next_token);
velocityBoundaryArray++;
velocityBoundaryArray[strlen(velocityBoundaryArray) - 1] = 0;
velocityBoundary = strtok_s(velocityBoundaryArray, ",", &token);
while (velocityBoundary != NULL) {
velocityBoundaries.push_back(strtod(velocityBoundary, NULL));
velocityBoundary = strtok_s(NULL, ",", &token);
}
atmosphereModel = strtok_s(NULL, ":", &next_token);
dragModel = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
stabilityFactor = strtod(strtok_s(NULL, ":", &next_token), NULL);
twistDirection = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
muzzleVelocity = strtod(strtok_s(NULL, ":", &next_token), NULL);
transonicStabilityCoef = strtod(strtok_s(NULL, ":", &next_token), NULL);
originArray = strtok_s(NULL, ":", &next_token);
originArray++;
originArray[strlen(originArray) - 1] = 0;
originEntry = strtok_s(originArray, ",", &token);
while (originEntry != NULL) {
origin.push_back(strtod(originEntry, NULL));
originEntry = strtok_s(NULL, ",", &token);
}
latitude = strtod(strtok_s(NULL, ":", &next_token), NULL);
temperature = strtod(strtok_s(NULL, ":", &next_token), NULL);
altitude = strtod(strtok_s(NULL, ":", &next_token), NULL);
humidity = strtod(strtok_s(NULL, ":", &next_token), NULL);
overcast = strtod(strtok_s(NULL, ":", &next_token), NULL);
tickTime = strtod(strtok_s(NULL, ":", &next_token), NULL);
tickTime += strtod(strtok_s(NULL, ":", &next_token), NULL);
while (index >= bulletDatabase.size()) {
Bullet bullet;
bulletDatabase.push_back(bullet);
}
bulletDatabase[index].airFriction = airFriction;
bulletDatabase[index].ballisticCoefficients = ballisticCoefficients;
bulletDatabase[index].velocityBoundaries = velocityBoundaries;
bulletDatabase[index].atmosphereModel = atmosphereModel;
bulletDatabase[index].dragModel = dragModel;
bulletDatabase[index].stabilityFactor = stabilityFactor;
bulletDatabase[index].twistDirection = twistDirection;
bulletDatabase[index].transonicStabilityCoef = transonicStabilityCoef;
bulletDatabase[index].muzzleVelocity = muzzleVelocity;
bulletDatabase[index].origin = origin;
bulletDatabase[index].latitude = latitude / 180 * M_PI;
bulletDatabase[index].temperature = temperature;
bulletDatabase[index].altitude = altitude;
bulletDatabase[index].humidity = humidity;
bulletDatabase[index].overcast = overcast;
bulletDatabase[index].startTime = tickTime;
bulletDatabase[index].lastFrame = tickTime;
bulletDatabase[index].hDeflection = 0.0;
bulletDatabase[index].spinDrift = 0.0;
bulletDatabase[index].speed = 0.0;
bulletDatabase[index].frames = 0.0;
bulletDatabase[index].randSeed = 0;
strncpy_s(output, outputSize, "", _TRUNCATE);
EXTENSION_RETURN();
} else if (!strcmp(mode, "simulate")) {
// simulate:0:[-0.109985,542.529,-3.98301]:[3751.57,5332.23,214.252]:[0.598153,2.38829,0]:28.6:0:0.481542:0:215.16
unsigned int index = 0;
char* velocityArray;
double velocity[3] = { 0.0, 0.0, 0.0 };
char* positionArray;
double position[3] = { 0.0, 0.0, 0.0 };
char* windArray;
double wind[3];
double heightAGL = 0.0;
double tickTime = 0.0;
index = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
velocityArray = strtok_s(NULL, ":", &next_token);
velocityArray++;
velocityArray[strlen(velocityArray) - 1] = 0;
velocity[0] = strtod(strtok_s(velocityArray, ",", &token), NULL);
velocity[1] = strtod(strtok_s(NULL, ",", &token), NULL);
velocity[2] = strtod(strtok_s(NULL, ",", &token), NULL);
positionArray = strtok_s(NULL, ":", &next_token);
positionArray++;
positionArray[strlen(positionArray) - 1] = 0;
position[0] = strtod(strtok_s(positionArray, ",", &token), NULL);
position[1] = strtod(strtok_s(NULL, ",", &token), NULL);
position[2] = strtod(strtok_s(NULL, ",", &token), NULL);
windArray = strtok_s(NULL, ":", &next_token);
windArray++;
windArray[strlen(windArray) - 1] = 0;
wind[0] = strtod(strtok_s(windArray, ",", &token), NULL);
wind[1] = strtod(strtok_s(NULL, ",", &token), NULL);
wind[2] = strtod(strtok_s(NULL, ",", &token), NULL);
heightAGL = strtod(strtok_s(NULL, ":", &next_token), NULL);
tickTime = strtod(strtok_s(NULL, ":", &next_token), NULL);
tickTime += strtod(strtok_s(NULL, ":", &next_token), NULL);
if (bulletDatabase[index].randSeed == 0) {
int angle = (int)round(atan2(velocity[0], velocity[1]) * 360 / M_PI);
bulletDatabase[index].randSeed = (unsigned)(720 + angle) % 720;
bulletDatabase[index].randSeed *= 3;
bulletDatabase[index].randSeed += (unsigned)round(abs(velocity[2]) / 2);
bulletDatabase[index].randSeed *= 3;
bulletDatabase[index].randSeed += (unsigned)round(abs(bulletDatabase[index].origin[0] / 2));
bulletDatabase[index].randSeed *= 3;
bulletDatabase[index].randSeed += (unsigned)round(abs(bulletDatabase[index].origin[1] / 2));
bulletDatabase[index].randSeed *= 3;
bulletDatabase[index].randSeed += (unsigned)abs(bulletDatabase[index].temperature) * 10;
bulletDatabase[index].randSeed *= 3;
bulletDatabase[index].randSeed += (unsigned)abs(bulletDatabase[index].humidity) * 10;
bulletDatabase[index].randGenerator.seed(bulletDatabase[index].randSeed);
}
double ballisticCoefficient = 1.0;
double dragRef = 0.0;
double drag = 0.0;
double accelRef[3] = { 0.0, 0.0, 0.0 };
double accel[3] = { 0.0, 0.0, 0.0 };
double TOF = 0.0;
double deltaT = 0.0;
double bulletSpeed;
double bulletDir;
double bulletSpeedAvg = 0.0;
double trueVelocity[3] = { 0.0, 0.0, 0.0 };
double trueSpeed = 0.0;
double temperature = 0.0;
double pressure = 1013.25;
double windSpeed = 0.0;
double windAttenuation = 1.0;
double velocityOffset[3] = { 0.0, 0.0, 0.0 };
double positionOffset[3] = { 0.0, 0.0, 0.0 };
TOF = tickTime - bulletDatabase[index].startTime;
deltaT = tickTime - bulletDatabase[index].lastFrame;
bulletDatabase[index].lastFrame = tickTime;
bulletSpeed = sqrt(pow(velocity[0], 2) + pow(velocity[1], 2) + pow(velocity[2], 2));
bulletDir = atan2(velocity[0], velocity[1]);
bulletDatabase[index].speed += bulletSpeed;
bulletDatabase[index].frames += 1;
bulletSpeedAvg = (bulletDatabase[index].speed / bulletDatabase[index].frames);
windSpeed = sqrt(pow(wind[0], 2) + pow(wind[1], 2) + pow(wind[2], 2));
if (windSpeed > 0.1) {
double windSourceTerrain[3];
windSourceTerrain[0] = position[0] - wind[0] / windSpeed * 100;
windSourceTerrain[1] = position[1] - wind[1] / windSpeed * 100;
windSourceTerrain[2] = position[2] - wind[2] / windSpeed * 100;
int gridX = (int)floor(windSourceTerrain[0] / 50);
int gridY = (int)floor(windSourceTerrain[1] / 50);
int gridCell = gridX * map->mapGrids + gridY;
if (gridCell >= 0 && (std::size_t)gridCell < map->gridHeights.size() && (std::size_t)gridCell < map->gridBuildingNums.size()) {
double gridHeight = map->gridHeights[gridCell];
if (gridHeight > position[2]) {
double angle = atan((gridHeight - position[2]) / 100);
windAttenuation *= pow(abs(cos(angle)), 2);
}
}
}
if (windSpeed > 0.1) {
double windSourceObstacles[3];
windSourceObstacles[0] = position[0] - wind[0] / windSpeed * 25;
windSourceObstacles[1] = position[1] - wind[1] / windSpeed * 25;
windSourceObstacles[2] = position[2] - wind[2] / windSpeed * 25;
if (heightAGL > 0 && heightAGL < 20) {
double roughnessLength = calculateRoughnessLength(windSourceObstacles[0], windSourceObstacles[1]);
windAttenuation *= abs(log(heightAGL / roughnessLength) / log(20 / roughnessLength));
}
}
if (windAttenuation < 1) {
wind[0] *= windAttenuation;
wind[1] *= windAttenuation;
wind[2] *= windAttenuation;
windSpeed = sqrt(pow(wind[0], 2) + pow(wind[1], 2) + pow(wind[2], 2));
}
trueVelocity[0] = velocity[0] - wind[0];
trueVelocity[1] = velocity[1] - wind[1];
trueVelocity[2] = velocity[2] - wind[2];
trueSpeed = sqrt(pow(trueVelocity[0], 2) + pow(trueVelocity[1], 2) + pow(trueVelocity[2], 2));
temperature = bulletDatabase[index].temperature - 0.0065 * position[2];
pressure = (1013.25 - 10 * bulletDatabase[index].overcast) * pow(1 - (0.0065 * (bulletDatabase[index].altitude + position[2])) / (273.15 + temperature + 0.0065 * bulletDatabase[index].altitude), 5.255754495);
if (bulletDatabase[index].ballisticCoefficients.size() == bulletDatabase[index].velocityBoundaries.size() + 1) {
dragRef = deltaT * bulletDatabase[index].airFriction * bulletSpeed * bulletSpeed;
accelRef[0] = (velocity[0] / bulletSpeed) * dragRef;
accelRef[1] = (velocity[1] / bulletSpeed) * dragRef;
accelRef[2] = (velocity[2] / bulletSpeed) * dragRef;
velocityOffset[0] -= accelRef[0];
velocityOffset[1] -= accelRef[1];
velocityOffset[2] -= accelRef[2];
ballisticCoefficient = bulletDatabase[index].ballisticCoefficients[0];
for (int i = (int)bulletDatabase[index].velocityBoundaries.size() - 1; i >= 0; i = i - 1) {
if (bulletSpeed < bulletDatabase[index].velocityBoundaries[i]) {
ballisticCoefficient = bulletDatabase[index].ballisticCoefficients[i + 1];
break;
}
}
ballisticCoefficient = calculateAtmosphericCorrection(ballisticCoefficient, temperature, pressure, bulletDatabase[index].humidity, bulletDatabase[index].atmosphereModel);
drag = deltaT * calculateRetard(bulletDatabase[index].dragModel, ballisticCoefficient, trueSpeed);
accel[0] = (trueVelocity[0] / trueSpeed) * drag;
accel[1] = (trueVelocity[1] / trueSpeed) * drag;
accel[2] = (trueVelocity[2] / trueSpeed) * drag;
velocityOffset[0] -= accel[0];
velocityOffset[1] -= accel[1];
velocityOffset[2] -= accel[2];
} else {
double airDensity = calculateAirDensity(temperature, pressure, bulletDatabase[index].humidity);
double airFriction = bulletDatabase[index].airFriction * airDensity / STD_AIR_DENSITY_ICAO;
if (airFriction != bulletDatabase[index].airFriction || windSpeed > 0) {
dragRef = deltaT * bulletDatabase[index].airFriction * bulletSpeed * bulletSpeed;
accelRef[0] = (velocity[0] / bulletSpeed) * dragRef;
accelRef[1] = (velocity[1] / bulletSpeed) * dragRef;
accelRef[2] = (velocity[2] / bulletSpeed) * dragRef;
velocityOffset[0] -= accelRef[0];
velocityOffset[1] -= accelRef[1];
velocityOffset[2] -= accelRef[2];
drag = deltaT * airFriction * trueSpeed * trueSpeed;
accel[0] = (trueVelocity[0] / trueSpeed) * drag;
accel[1] = (trueVelocity[1] / trueSpeed) * drag;
accel[2] = (trueVelocity[2] / trueSpeed) * drag;
velocityOffset[0] += accel[0];
velocityOffset[1] += accel[1];
velocityOffset[2] += accel[2];
}
}
if (bulletSpeedAvg > 0) {
double distanceSqr = pow(bulletDatabase[index].origin[0] - position[0], 2) + pow(bulletDatabase[index].origin[1] - position[1], 2) + pow(bulletDatabase[index].origin[2] - position[2], 2);
double horizontalDeflection = 0.0000729 * distanceSqr * sin(bulletDatabase[index].latitude) / bulletSpeedAvg;
double horizontalDeflectionPartial = horizontalDeflection - bulletDatabase[index].hDeflection;
bulletDatabase[index].hDeflection = horizontalDeflection;
positionOffset[0] += sin(bulletDir + M_PI / 2) * horizontalDeflectionPartial;
positionOffset[1] += cos(bulletDir + M_PI / 2) * horizontalDeflectionPartial;
}
double centripetalAccel = 2 * 0.0000729 * (bulletDatabase[index].muzzleVelocity) * cos(bulletDatabase[index].latitude) * sin(bulletDir);
velocityOffset[2] += centripetalAccel * deltaT;
double spinDrift = bulletDatabase[index].twistDirection * 0.0254 * 1.25 * (bulletDatabase[index].stabilityFactor + 1.2) * pow(TOF, 1.83);
double spinDriftPartial = spinDrift - bulletDatabase[index].spinDrift;
bulletDatabase[index].spinDrift = spinDrift;
positionOffset[0] += sin(bulletDir + M_PI / 2) * spinDriftPartial;
positionOffset[1] += cos(bulletDir + M_PI / 2) * spinDriftPartial;
double speedOfSound = 331.3 + (0.6 * temperature);
if (bulletSpeed < (speedOfSound + 5) && bulletSpeedAvg > speedOfSound && bulletSpeed > (speedOfSound - 5)) {
std::uniform_real_distribution<double> distribution(0.0, 1.0);
double coef = 1.0f - bulletDatabase[index].transonicStabilityCoef;
velocityOffset[0] += (distribution(bulletDatabase[index].randGenerator) * 0.8 - 0.4) * coef;
velocityOffset[1] += (distribution(bulletDatabase[index].randGenerator) * 0.8 - 0.4) * coef;
velocityOffset[2] += (distribution(bulletDatabase[index].randGenerator) * 0.8 - 0.4) * coef;
};
outputStr << "_bullet setVelocity (_bulletVelocity vectorAdd [" << velocityOffset[0] << "," << velocityOffset[1] << "," << velocityOffset[2] << "]); _bullet setPosASL (_bulletPosition vectorAdd [" << positionOffset[0] << "," << positionOffset[1] << "," << positionOffset[2] << "]);";
strncpy_s(output, outputSize, outputStr.str().c_str(), _TRUNCATE);
EXTENSION_RETURN();
} else if (!strcmp(mode, "set")) {
int height = 0;
int numObjects = 0;
int surfaceIsWater = 0;
height = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
numObjects = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
surfaceIsWater = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
map->gridHeights.push_back(height);
map->gridBuildingNums.push_back(numObjects);
map->gridSurfaceIsWater.push_back(surfaceIsWater);
strncpy_s(output, outputSize, outputStr.str().c_str(), _TRUNCATE);
EXTENSION_RETURN();
} else if (!strcmp(mode, "init")) {
int mapSize = 0;
int mapGrids = 0;
int gridCells = 0;
worldName = strtok_s(NULL, ":", &next_token);
mapSize = strtol(strtok_s(NULL, ":", &next_token), NULL, 10);
mapGrids = (int)ceil((double)mapSize / 50.0) + 1;
gridCells = mapGrids * mapGrids;
map = &mapDatabase[worldName];
if (map->gridHeights.size() == gridCells) {
outputStr << "Terrain already initialized";
strncpy_s(output, outputSize, outputStr.str().c_str(), _TRUNCATE);
EXTENSION_RETURN();
}
map->mapSize = mapSize;
map->mapGrids = mapGrids;
map->gridHeights.clear();
map->gridBuildingNums.clear();
map->gridSurfaceIsWater.clear();
map->gridHeights.reserve(gridCells);
map->gridBuildingNums.reserve(gridCells);
map->gridSurfaceIsWater.reserve(gridCells);
strncpy_s(output, outputSize, outputStr.str().c_str(), _TRUNCATE);
EXTENSION_RETURN();
}
strncpy_s(output, outputSize, outputStr.str().c_str(), _TRUNCATE);
EXTENSION_RETURN();
}