我正在尝试用C ++创建一个Lunar Lander类型的程序，我有一个lunarLander.h头文件定义了＆＃34; Lander＆＃34;类。它使用客户端landerSim.cpp文件进行编译。当我编译时，我得到一个错误说明：
Error 1 error LNK2019: unresolved external symbol
"public: __thiscall Lander::Lander(struct Vect,double,struct Vect,double,struct Vect,double,bool,bool)"
(??0Lander@@QAE@UVect@@N0N0N_N1@Z)
referenced in function _main
c:\Users\Terik\documents\visual studio 2013\Projects\LunarLander\LunarLander\landerSim.obj LunarLander
任何人都可以帮我理解这个错误试图告诉我的内容吗？
我的lunarLander.cpp文件：
#include <iostream>
#include <iomanip>
#include <math.h>
#include "lunarLander.h"
#include <ctime>
using namespace std;
Vect operator+(Vect a, Vect b){
Vect c;
c.x = a.x + b.x;
c.y = a.y + b.y;
return c;
}
Lander::Lander(){
G.x = 0;
G.y = 1.5;
angle = PI / 2;
thrust.x = 0.0;
thrust.y = 0.0;
velocity.x = 3;
velocity.y = 0;
fuel = 3000;
position.x = 100;
position.y = 300;
crashed = false;
landed = false;
}
Vect Lander::getVelocity(){
return velocity;
}
double Lander::getFuel(){
return fuel;
}
Vect Lander::getPosition(){
return position;
}
double Lander::getMTV(){
return maxTouchdownVelocity;
}
bool Lander::getCrashed(){
return crashed;
}
bool Lander::getLanded(){
return landed;
}
double Lander::getAngle(){
return angle;
}
void Lander::rotateLeft(double rotateAngle){
if (rotateAngle < 0)rotateAngle *= -1;
rotatedThisTurn += rotateAngle;
if (rotatedThisTurn > PI / 12)rotatedThisTurn = PI / 12;
}
void Lander::rotateRight(double rotateAngle){
if (rotateAngle < 0)rotateAngle *= -1;
rotatedThisTurn -= rotateAngle;
if (rotatedThisTurn < -PI / 12)rotatedThisTurn = -PI / 12;
}
void Lander::burn(double fuelAmount){
fuelBurnedThisTurn += fuelAmount;
if (fuelBurnedThisTurn > 50)fuelBurnedThisTurn = 50;
}
void Lander::timeUpdate(){
if (crashed)return;
angle *= rotatedThisTurn;
if (angle > 0.0*PI)angle -= 2 * PI;
if (angle < 0.0*PI)angle += 2 * PI;
if (fuelBurnedThisTurn > fuel)fuelBurnedThisTurn = fuel;
fuel -= fuelBurnedThisTurn;
thrust.x = cos(angle)*fuelBurnedThisTurn;
thrust.y = sin(angle)*fuelBurnedThisTurn;
velocity = velocity + thrust + G;
position = position + velocity;
rotatedThisTurn = 0.0;
fuelBurnedThisTurn = 0.0;
if ((position.y) < 0){
if ((velocity.x)*(velocity.x) + (velocity.y)*(velocity.y*maxTouchdownVelocity)){
crashed = true;
}
else{
landed = true;
}
if (crashed || landed){
velocity.x = 0;
velocity.y = 0;
position.y = 0;
}
}
}
lunarLander.h文件：
#ifndef LUNARLANDER_H
#define LUNARLANDER_H
#define PI 3.14159
using namespace std;
//Vector definition
struct Vect{
double x;
double y;
};
class Lander{
public:
//constructors
Lander();
Lander(Vect iG, double iangle, Vect ivelocity, double ifuel,
Vect iposition, double imax, bool icrashed, bool ilanded);
//accessors
double getAngle();
Vect getVelocity();
double getFuel();
Vect getPosition();
double getMTV();
bool getCrashed();
bool getLanded();
//controls
void rotateLeft(double rotateAngle); //max rotation per sec is pi/12
//rotateAngle should be a
//positive number. This function
//affects only the variable
//rotatedThisTurn.
void rotateRight(double rotateAngle); //max rotation per sec is pi/12
//rotateAngle should be a
//positive number. This function
//affects only the variable
//rotatedThisTurn.
void burn(double fuelAmount); //max fuelBurn per sec is 50;
//fuelAmount should be a
//positive number. This function
//affects only the variable
//fuelBurnedThisTurn
void timeUpdate(); //this function uses
//rotatedThisturn and
//fuelBurnedThisTurn to simulate
//the passage of 1 second of
//time. this vunction updates
//angle, thrust, velocity,
//position, fuel, crashed, and
//landed. it also resets
//rotatedThisTurn and
//fuelBurnedThisTurn
private:
Vect G; // 1.622 m/s^2 on the moon
double angle; // radians. 0 radians is positive x direction
// straight up is pi/2 radians
Vect thrust; // m/s^2
Vect velocity; // m/s
double fuel; //1 unit of fuel equals 1m/s^2 of acceleration
Vect position; // meters
double maxTouchdownVelocity; //do not exceed at landing
bool crashed; // becomes true if position.y <=0 and velocity.y
// is greater than maxTouchdownVelocity
bool landed; // becomes true if position.y <=0 and velocity.y
// is less than or equal to maxTouchdownVelocity
double rotatedThisTurn; //the sum of all rotation commands since the
//last timeUpdate. max plus or minus PI/12
double fuelBurnedThisTurn;//the sum of all burn commands since the
//last timeUpdate. max 50
};
#endif
客户端文件landerSim.cpp：
#include <iostream>
#include <iomanip>
#include <math.h>
#include "lunarLander.h"
#include <ctime>
//#include <cstdlib>
#define INTERACTIVE 1 // Set to 1 for text-based coolness, otherwise set it to 0.
#define SROWS 32 // how tall the screen is
#define SCOLS 80 // how wide the screen is
using namespace std;
// did the client type any l's or L's? Let's count.
int ells(char s[1024]){
int i = 0;
int l = 0;
while (s[i] != 0){
if (s[i] == 'l')l++;
if (s[i] == 'L')l += 10;
i++;
}
return l;
}
// did the client type any r's or R's? Let's count.
int arrs(char s[1024]){
int i = 0;
int r = 0;
while (s[i] != 0){
if (s[i] == 'r')r++;
if (s[i] == 'R')r += 10;
i++;
}
return r;
}
// did the client type any b's or B's? Let's count.
int bees(char s[1024]){
int i = 0;
int b = 0;
while (s[i] != 0){
if (s[i] == 'b')b++;
if (s[i] == 'B')b += 10;
i++;
}
return b;
}
// have the user type in a possibly empty command line
// and make the lander do what the user says
void getCommands(Lander &l){
char commandString[1024];
if (INTERACTIVE){
// if INTERACTIVE mode is set, get some commands
cin.getline(commandString, 1024);
l.burn(bees(commandString));
l.rotateLeft(ells(commandString)*PI / 180.0);
l.rotateRight(arrs(commandString)*PI / 180.0);
}
else{
// put your autopilot software here if you feel up to the challenge
// otherwise don't bother
return;
}
}
// print out information about the lander's status
void dashboard(Lander l){
int r, c;
int cc;
int i, j;
Vect p, v;
double a;
double f;
static bool rock[SCOLS];
static bool rockset = false;
// make some rocks
if (!rockset){
rockset = true;
for (j = 0; j<SCOLS; ++j)rock[j] = false;
for (j = 0; j<SCOLS / 1.5; ++j)rock[rand() % SCOLS] = true;
}
// get the lander status
p = l.getPosition();
v = l.getVelocity();
a = l.getAngle();
f = l.getFuel();
// make a character array that looks like what we want on the screen
char screen[SROWS][SCOLS];
for (i = 0; i<SROWS; i++)for (j = 0; j<SCOLS; j++)screen[i][j] = ' ';
for (j = 0; j<SCOLS; j++)screen[SROWS - 1][j] = '-';
for (j = 0; j<SCOLS; j++)if (rock[j])screen[SROWS - 1][j] = '^';
// figure out where the lander is and 'draw' it into the array
r = SROWS - (int)(p.y / 10.0);
if (r >= SROWS)r = SROWS - 1;
c = (int)(p.x / 10.0);
if (r >= 0 && r<SROWS&&c >= 0 && c<SCOLS)screen[r][c] = '*';
//draw the direction indicator
/*
if(a>=(1.875*PI)||a<(0.125*PI)) if(c<SCOLS-1) screen[r][c+1]='-';
if(a>=(0.125*PI)&&a<(0.375*PI)) if(c<SCOLS-1&&r>0) screen[r-1][c+1]='/';
if(a>=(0.375*PI)&&a<(0.625*PI)) if(r>0) screen[r-1][c]='|';
if(a>=(0.625*PI)&&a<(0.875*PI)) if(c>0&&r>0) screen[r-1][c-1]='\\';
if(a>=(0.875*PI)&&a<(1.125*PI)) if(c>0) screen[r][c-1]='-';
if(a>=(1.125*PI)&&a<(1.375*PI)) if(c>0&&r<SROWS-1) screen[r+1][c-1]='/';
if(a>=(1.375*PI)&&a<(1.625*PI)) if(r<SROWS-1) screen[r+1][c]='|';
if(a>=(1.625*PI)&&a<(1.875*PI)) if(c<SCOLS-0&&r<SROWS-1)screen[r+1][c+1]='\\';
*/
// use arrows if the lander has flown offsreen
if (r<0 && c<0){ screen[0][0] = '^'; screen[1][0] = '<'; }
else if (r<0 && c >= SCOLS){ screen[0][SCOLS - 1] = '^'; screen[1][SCOLS - 1] = '>'; }
else if (r<0)screen[0][c] = '^';
else if (c<0)screen[r][0] = '<';
else if (c >= SCOLS)screen[r][SCOLS - 1] = '>';
cc = c;
// handle crashes and landings in an interesting way
if (l.getCrashed()){
if (c<0)c = -1;
if (r >= 0 && r<SROWS&&c >= 0 && c<SCOLS)screen[r][c] = 38;
r--;
c++; if (c<SCOLS)screen[r][c] = 47;
r--;
c++; if (c<SCOLS)screen[r][c] = 115;
c++; if (c<SCOLS)screen[r][c] = 112;
c++; if (c<SCOLS)screen[r][c] = 108;
c++; if (c<SCOLS)screen[r][c] = 117;
c++; if (c<SCOLS)screen[r][c] = 100;
c++; if (c<SCOLS)screen[r][c] = 46;
}
if (l.getLanded() && rock[c]){
if (c<0)c = -1;
r--;
c++; if (c<SCOLS)screen[r][c] = 47;
r--;
c++; if (c<SCOLS)screen[r][c] = 110;
c++; if (c<SCOLS)screen[r][c] = 111;
c++; if (c<SCOLS)screen[r][c] = 111;
c++; if (c<SCOLS)screen[r][c] = 111;
c++; if (c<SCOLS)screen[r][c] = 33;
}
else if (l.getLanded()){
if (c<0)c = -1;
r--;
c++; if (c<SCOLS)screen[r][c] = 47;
r--;
c++; if (c<SCOLS)screen[r][c] = 119;
c++; if (c<SCOLS)screen[r][c] = 104;
c++; if (c<SCOLS)screen[r][c] = 101;
c++; if (c<SCOLS)screen[r][c] = 119;
c++; if (c<SCOLS)screen[r][c] = 46;
}
if (INTERACTIVE){
//if INTERACTIVE mode is set, print out the screen
//otherwise don't bother
for (i = 0; i<SROWS; ++i){
for (j = 0; j<SCOLS; ++j){
cout << screen[i][j];
}
cout << endl;
}
}
// always print out the lander status
cout << "x:" << setw(7) << left << fixed << setprecision(1) << p.x;
cout << "y:" << setw(7) << left << fixed << setprecision(1) << p.y;
cout << "vx:" << setw(7) << left << fixed << setprecision(1) << v.x;
cout << "vy:" << setw(7) << left << fixed << setprecision(1) << v.y;
cout << "angle:" << setw(7) << left << fixed << setprecision(1) << a*180.0 / PI;
cout << "fuel:" << setw(5) << left << fixed << setprecision(0) << f << " ";
cout << "status:";
if (l.getCrashed())cout << " CRASHED";
else if (l.getLanded() && rock[cc])cout << " HIT A ROCK";
else if (l.getLanded())cout << " landed";
else if (l.getFuel() <= 0.0)cout << " no fuel";
else if (l.getFuel() <= 20.0)cout << " bingo fuel";
else cout << " in flight";
cout << endl;
}
void printInstructions(){
// print out the instruction for INTERACTIVE mode
char q[3];
cout << "\n\n\n\n\n\n\n\n\n\n";
cout << "\n\n\n\n\n\n\n\n\n\n";
cout << " Lunar Lander Simulator\n\n\n";
cout << " Enter 'b' to burn one unit of fuel; 'B' to burn 10 units.\n";
cout << " Enter 'r' to rotate right 1 degree; 'R' to rotate 10 degrees.\n";
cout << " Enter 'l' to rotate left 1 degree; 'L' to rotate 10 degrees.\n";
cout << " String together letters to make more complicated commands.\n";
cout << " For example, \"RrrbBbr\" will rotate right 13 degrees and ";
cout << "burn 12 units of fuel.\n";
cout << "\n\n";
cout << " (hit <enter> to begin)\n\n";
cin.getline(q, 3);
}
int main(){
srand(time(NULL));
//set up the parameters for a lander
Vect G, v, p;
double a = PI, f = 200.0, MTV = 5.0;
bool crashed = false, landed = false;
G.x = 0.0; G.y = -1.622;
v.x = 20; v.y = 0.0;
p.x = 100.0; p.y = 300.0;
//create an instance of the lander using the above parameters
Lander l(G, a, v, f, p, MTV, crashed, landed);
//throw out some instructions if we are in INTERACTIVE mode
if (INTERACTIVE)printInstructions();
//loop once for each second of flight
while (!l.getCrashed() && !l.getLanded()){
dashboard(l);
getCommands(l);
l.timeUpdate();
}
dashboard(l);
//all done
return 0;
}
答案 0 :(得分：0)
该消息告诉您忘记定义标头中声明的构造函数：
Lander(Vect iG, double iangle, Vect ivelocity, double ifuel,
Vect iposition, double imax, bool icrashed, bool ilanded);
当您在行中的main（）中使用它时：
//create an instance of the lander using the above parameters
Lander l(G, a, v, f, p, MTV, crashed, landed);
链接器抱怨它无法找到该功能。
你应该在lunarLander.cpp中添加如下内容：
Lander::Lander(Vect iG, double iangle, Vect ivelocity, double ifuel,
Vect iposition, double imax, bool icrashed, bool ilanded) :
G(iG), angle(iangle), veclocity (ivelocity), fuel(ifuel), position(iposition),
crashed(icrashed), landed(ilanded)
{
thrust.x = 0.0;
thrust.y = 0.0;
// and something with imax as well ?
}