OpenGL camera errors..can't find 'em!?

ok...i'm putting togeather my camera code, with the first OpenGL camera tutorial from gametutorials.com as a guide...anyway...i'm using DevC++, and it's putting out errors, but i can't find them (well i kno where they should be but i dont see 'em ;) )

anyway...here's my camera.cpp:

Code:

---

#include <windows.h>
#include <gl/gl.h>
#include "camera.h"

//camera constructor
CCamera :: CCamera()
{
CVector3 vZero = {0.0, 0.0, 0.0};
CVector3 vView = {0.0, 1.0, 0.5);
CVector3 vUp = {0.0, 0.0, 1.0};

C_vPosition = vZero;
C_vView = vView;
C_vUpVector = vUp;
}

//position camera
CCamera :: PositionCamera(int positionX, int positionY, int positionZ,
int viewX,    int viewY,    int viewZ,
int upVectorX, int upVectorY, int upVectorZ)
{
CVector3 vPosition        = {positionX, positionY, positionZ};
CVector3 vView                = {viewX, viewY, viewZ};
CVector3 vUpVector        = {upVectorX, upVectorY, upVectorZ};

C_vPosition = vPosition;
C_vView = vView;
C_vUpVector = C_vUpVector;
}

---

errors:
-end of file read inside definition ~ line7
-'CCamera :: CCamera()' has already been declared in 'CCamera' ~ line7
-parse error at end of input ~ line30

the camera.h code:

Code:

---

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <gl\gl.h>

//vector class
class CVector3
{
public:
int x, y, z;
};

//camera class
class CCamera
{
public:
CVector C_vPosition; //camera position
CVector C_vView;    //camera view
CVector C_vUpVector; //camera 'up' vector

CCamera(); //camera constructor

//values for camera positioning
int PositionX, PositionY, PositionZ;
int ViewX, ViewY, ViewZ;
int UpVectorX, UpVectorY, UpVectorZ;

void PositionCamera(int positionX, int positionY, int positionZ,
                                            int viewX,    int viewY,    int viewZ,
                                                int upVectorX, int upVectorY, int upVectorZ);

//camera movement
int speed;
MoveCamera(speed);

//extern values so they can be accessed globally
extern CCamera gl_Camera;

---

errors:
-syntax error befor ';' ~ line 19
-syntax error before ';' ~ line20
-invalid use of member 'CCamera::speed' ~ line35
-ANSI C++ forbids declaration 'MoveCamera' with no type ~ line35
-storage class specified for feild 'gl_Camera' ~ line38
-field 'gl_Camera' has incomplete type ~ line38


anyway....if anyone can help i'll be very grateful

-psychopath

How bout adding a }; to the end of your camera.h

ok...same .h errors...and new .cpp errors:
-return type specification for constructor invalid
-warning: initilization to 'int' from 'double' (that happend 9 times, 3 on line 9, 10, and eleven)
-C_vPosition undeclared
-C_vView undeclared
-C-vUpVector undeclared
-ANSI c++ forbids declaration of 'Position Camera' with no type
-new declaration 'int CCamera :: PositionCamera(int, int, int, int, int, int, int, int, int)'
ambiguates old declaration 'void CCamera :: PositionCamera(int, int, int, int, int, int, int, int, int)' <-(in the .h file)


-psychopath

>CVector3 vView = {0.0, 1.0, 0.5);
That should be a brace at the end.

did that...still dosn't work :(

Well first of all, you called your vector class CVector3, but in your CCamera class you called it CVector.

The whole 'int to double' thing happens because you put '0.0' instead of just 0. Your vector class as it is handles integers, which cannot have decimal points. If you need decimal points you need to change your CVector3 class to have float x, y, z or double x, y, z.

In camera.cpp you should put void CCamera :: PositionCamera()

In camera.h you should have void MoveCamera()

Inside of MoveCamera in camera.h you need to have a variable type, not just a variable name, like int speed, float speed, or double speed.


Hope that helps.

ok heres my code now:

camera.cpp

Code:

---

#include <windows.h>
#include <gl/gl.h>
#include "camera.h"

//camera constructor
CCamera :: CCamera()
{
CVector3 vZero = {0.0, 0.0, 0.0};
CVector3 vView = {0.0, 1.0, 0.5};
CVector3 vUp = {0.0, 0.0, 1.0};

C_vPosition = vZero;
C_vView = vView;
C_vUpVector = vUp;
};


//position camera
void CCamera :: PositionCamera(float positionX, float positionY, float positionZ,
float viewX,    float viewY,    float viewZ,
float upVectorX, float upVectorY, float upVectorZ)
{
CVector3 vPosition = {positionX, positionY, positionZ};
CVector3 vView = {viewX, viewY, viewZ};
CVector3 vUpVector = {upVectorX, upVectorY, upVectorZ};

C_vPosition = vPosition;
C_vView = vView;
C_vUpVector = C_vUpVector;
};

---

camera.h

Code:

---

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <gl\gl.h>

//vector class
class CVector3
{
public:
float x, y, z;
};

//camera class
class CCamera
{
public:
CVector3 C_vPosition; //camera position
CVector3 C_vView;    //camera view
CVector3 C_vUpVector; //camera 'up' vector

CCamera(); //camera constructor

//values for camera positioning
float PositionX, PositionY, PositionZ;
float ViewX, ViewY, ViewZ;
float UpVectorX, UpVectorY, UpVectorZ;

//camera movement
float speed;
void MoveCamera(float speed);

//extern values so they can be accessed globally
extern CCamera gl_Camera;
};

---

first of all:
>>you need to have a variable type, not just a variable name<<
can i have an example (not really sure of what you mean)

and now the only errors are:

camera.h:
feild 'gl_Camera' has incomplete type (you told me about that one but i'm not sure how to fix it (as stated above :P ))

camera.cpp:
no void CCamera :: PositionCamera(float, float, float,
float, float, float, float, float, float) member function declared in class 'CCamera'

anyway what you told me really helped...i like it when the error output gets chopped down to almost working :P

Quote:

---

//vector class
class CVector3
{
public:
int x, y, z;
};

//camera class
class CCamera
{
public:
CVector C_vPosition; //camera position
CVector C_vView; //camera view
CVector C_vUpVector; //camera 'up' vector

CCamera(); //camera constructor

//values for camera positioning
int PositionX, PositionY, PositionZ;
int ViewX, ViewY, ViewZ;
int UpVectorX, UpVectorY, UpVectorZ;
...
};

---

This only handles integers. If there are no vector classes already defined for you then here is a possible solution to handle any data type.

Code:

---

//vector class
template <class Class_Type> CVector3
{
  public:
    CVector3() {}
    CVector3(Class_Type x,Class_Type y,Class_Type z):x(x),y(y),z(z) {}
    Class_Type x, y, z;
};

//camera class
class CCamera
{
public:
  CVector3<float> C_vPosition; //camera position
  CVector3<float> C_vView;    //camera view
  CVector3<float> C_vUpVector; //camera 'up' vector

  CCamera(); //camera constructor

  //values for camera positioning
  CVector3<float> Position;
  CVector3<float> View;
  CVector3<float> UpVector;

...
};

---

But shouldn't those variables relative to camera be at least declared as protected instead of public??

hmm.....ok after much work to the code, i got it to work....then I added the movement code.....in my 'mainprog.cpp'...it says 'unidentified reference to 'gl_Camera' ...sorry theres no code posted..i'm in school right now....if there are no replies before i get home, then i'll post the code...if not.......but otherwise, does anyone know why i would be getting this error?

ok...here it is.....in the camera.h i did:

extern CCamera gl_Camera;

in the mainprog.cpp:

Code:

---

glClearColor( 0.0f, 0.0f, 0.0f, 0.0f );
glClear( GL_COLOR_BUFFER_BIT );

gluLookAt(gl_Camera.C_vPosition.x, gl_Camera.C_vPosition.y, gl_Camera.C_vPosition.z,
                          gl_Camera.C_vView.x,          gl_Camera.C_vView.y,          gl_Camera.C_vView.z,
                          gl_Camera.C_vUpVector.x, gl_Camera.C_vUpVector.y, gl_Camera.C_vUpVector.z);

glPushMatrix();
glBegin( GL_POLYGON );
glColor3f( 1.0f, 1.0f, 0.0f ); glVertex3f( 1.0f, 1.0f, -1.0f );
glColor3f( 0.0f, 1.0f, 0.0f ); glVertex3f( 1.0f, -1.0f, -1.0f );
glColor3f( 0.0f, 0.0f, 1.0f ); glVertex3f( -1.0f, -1.0f, -1.0f );
glColor3f( 1.0f, 0.0f, 0.0f ); glVertex3f( -1.0f, 1.0f, -1.0f );
glEnd();
glPopMatrix();

SwapBuffers( hdc );

theta += 1.0f;

---

and:

Code:

---

case WM_KEYDOWN:
float speed;

switch ( wparam ) {

case VK_ESCAPE:
PostQuitMessage( 0 );
break;

case VK_UP:
gl_Camera.MoveCamera(speed); //move camera forward
void RenderScene();  //render the scene after movement
break;

case VK_DOWN:
gl_Camera.MoveCamera(-speed); //move camera backward
void RenderScene();  //render the scene after movement
break;
return 0;
}

---

those are the areas i get 'unidentified reference to gl_Camera...below is the camera.cpp and camera.h incase it might be important:

camera.cpp

Code:

---

#include <windows.h>
#include <gl/gl.h>
#include "include.h"

//camera constructor
CCamera :: CCamera()
{
CVector3 vZero = {0.0, 0.0, 0.0};
CVector3 vView = {0.0, 1.0, 0.5};
CVector3 vUp = {0.0, 0.0, 1.0};

C_vPosition = vZero;
C_vView = vView;
C_vUpVector = vUp;
};

//position camera
void CCamera :: PositionCamera(float positionX, float positionY, float positionZ,
float viewX,    float viewY,    float viewZ,
float upVectorX, float upVectorY, float upVectorZ)
{
CVector3 vPosition = {positionX, positionY, positionZ};
CVector3 vView = {viewX, viewY, viewZ};
CVector3 vUpVector = {upVectorX, upVectorY, upVectorZ};

C_vPosition = vPosition;
C_vView = vView;
C_vUpVector = C_vUpVector;
};

//move camera
void CCamera::MoveCamera(float speed)
{
CVector3 vVector = {0};

vVector.x = C_vView.x - C_vPosition.x;
vVector.y = C_vView.y - C_vPosition.y;
vVector.z = C_vView.z - C_vPosition.z;

C_vPosition.x += vVector.x * speed;
C_vPosition.z += vVector.z * speed;
C_vView.x += vVector.x * speed;
C_vView.z += vVector.z * speed;
};

---

camera.h

Code:

---

#include <windows.h>
#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <gl\gl.h>

//vector class
class CVector3
{
public:
float x, y, z;
};

//camera class
class CCamera
{
public:
CVector3 C_vPosition; //camera position
CVector3 C_vView;    //camera view
CVector3 C_vUpVector; //camera 'up' vector

CCamera(); //camera constructor

//values for camera positioning
void PositionCamera(float PositionX, float PositionY, float PositionZ,
                    float ViewX, float ViewY, float ViewZ,
                    float UpVectorX, float UpVectorY, float UpVectorZ);

//camera movement
float speed;
void MoveCamera(float speed);

};

//extern values so they can be accessed globally
extern CCamera gl_Camera;

---

-psychopath

You extern gl_Camera in camera.h. extern doesn't actually create an object, but rather tells that file "this object exists somewhere else, but act like it is declared here." You need to add a line in mainprog.cpp to make a global CCamera object, like:

CCamera gl_Camera;

Unless you use the gl_Camera object in camera.h, you don't need to include that extern line. Remove that, and you should be fine.

hmmm.....now it says:

multiple definition of 'gl_Camera'
first defined here:

Code:

---

gl_Camera.MoveCamera(speed);

---

-psychopath

hmm....it seems to do this even when i comment out all the references to gl_Camera!?