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strange camera behavior...

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Hello, i recently posted about getting a camera algorithm i came up with to work (post), well i finally got it to work (some what), i can look around completly, just like a first person camera, and i didnt have to do any crazy math to get it, i tryed adding a simple function to move the player (or camera), forward and backwords on the Z axis. In my test program i just have a flat square as the ground, with a brick wall sticking up. when i simply (try to) move the camera backwards or forwards, the terrain slides out rather quickly, and the brick wall moves back and forth really slow. This just seemed strange because i used glLoadIdentity(); before calling gluLookAt(), i wouldnt see how it would have any effect on the positioning of objects in the world, i feel like im making a stupid mistake here and im just not seeing it. You can download the ZIP file (here [1.02 MB]), or take a look at my camera class, and maybe see my stupid mistake?
class cCamera
	void UpdateCamera();

	~cCamera() {};

	void m_pUpdateCamera();

float PI = 3.14f;
float Radius = 20.0f;
float CameraPosX = 90.0f;
float CameraPosY = 0.0f;
float PlayerX = 0.0;
float PlayerZ = 0.0;

void cCamera::UpdateCamera()
	int x, y;	// mouse pos

	int middleX, middleY;	// middle of the window

	float angleX, angleY;

	// get the screen/2

	middleX = screen->w >> 1;
	middleY = screen->h >> 1;

	// get the current mouse position

	SDL_GetMouseState(&x, &y);

	// if the position is the center, then just stop

	if(x==middleX && y==middleY)

	angleX = (float)(middleX - x) / 100.0f;
	angleY = (float)(middleY - y) / 100.0f;

	CameraPosX -= angleX;
	CameraPosY -= angleY;

	SDL_WarpMouse(middleX, middleY);

	if(CameraPosX > 360.0)
		CameraPosX = 0.0;

	if(CameraPosX < 0.0)
		CameraPosX = 360.0;

	if(CameraPosY > 3.0)
		CameraPosY = 3.0f;

	if(CameraPosY < -3.0)
		CameraPosY = -3.0;


void cCamera::m_pUpdateCamera()
	gluLookAt(	PlayerX,		0.0,		PlayerZ,
				PlayerX + Radius*sin(CameraPosX/PI),	Radius*sin(CameraPosY/PI),	PlayerZ + Radius*cos(CameraPosX/PI),
				0.0,		-1.0,		0.0);
The error is when I +/- the PlayerZ, it has some strange effect on the world... --------------------------------------------- "If the automobile had followed the same development cycle as the computer, a Rolls-Royce would today cost $100, get a million miles per gallon, and explode once a year, killing everyone inside."

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