3D Camera Rotation | GameDev.net

I recentley whippped up a first person style camera class, lightly based off of other various 3D cameras online. However, it doesn't really work all that well. There is one line in specific that I think is causing the problem, which is the rotation on the x-axis line (see the line in the MouseLook function with the "THIS DOESN'T WORK" comment). If I comment this line out, the rest of the camera works fine (rotation on y-axis, moving back & forward, strafing) however when I leave it there, the camera goes insane. Here is the related camera source code (The language is C++, one line of graphics done with OpenGL, mouse input done with SDL) : Camera.h


#ifndef _CAMERA_H_
#define _CAMERA_H_

#include "Main.h"
#include "Vector3.h"
#include "Timer.h"

class Camera
{
public:
	Camera(Vector3 pos,Vector3 v,Vector3 u);
	void Move(float distance);
	void Strafe(float distance);
	void MouseLook();
	void Update();
	int height;
	int width;
	Vector3 view;
	Vector3 position;
	Vector3 up;
private:
	void Rotate(float angle, Vector3 speed);
	float angle; 
};

#endif

Camera.cpp


#include "Camera.h"

Camera::Camera(Vector3 pos, Vector3 v, Vector3 u)
{
	angle = 0;
	position = pos;
	view = v;
	up = u;
}

// Source code removed for brevity.

void Camera::MouseLook()
{
	int middleX = width / 2;
	int middleY = height / 2;
	int mouseX, mouseY;
	SDL_GetMouseState(&mouseX,&mouseY);
	SDL_WarpMouse(middleX, middleY);  
	if(mouseX == middleX && mouseY == middleY) return;

	float xRotation = (float)((middleX - mouseX)) / (float) width;
	float yRotation = (float)((middleY - mouseY)) / (float) height;
	angle -= yRotation;
	if(angle > 1.0f)
	{
		float difference = angle - 1.0f;
		yRotation -= difference;
		angle = 1.0f;
	}
	else if(angle < -1.0f)
	{
		float difference = -angle - 1.0f;
		yRotation += difference;
		angle = -1.0f;
	}

	Vector3 look(view - position);
	Vector3 xCameraAxis = look.Cross(up);
	xCameraAxis.Normalize();
	Rotate(yRotation, xCameraAxis); //THIS DOESN'T WORK
	Rotate(xRotation, up);
}

void Camera::Update()
{
	gluLookAt(position.x, position.y, position.z, view.x, view.y, view.z, up.x, up.y, up.z);
}

void Camera::Rotate(float angle, Vector3 speed)
{
	float cosine = (float)cos(angle);
	float sine = (float)sin(angle);
	Vector3 look(view-position);
	look.Normalize();
	Vector3 newLook;

	newLook.x = look.x * (speed.x * (1 - cosine) +  cosine) + 
				look.y * (speed.x * speed.y * (1 - cosine) - speed.z * sine) +
				look.z * (speed.x * speed.z * (1 - cosine) + speed.y * sine);

	newLook.y = look.y * (speed.y * (1 - cosine) +  cosine) + 
				look.x * (speed.x * speed.y * (1 - cosine) + speed.z * sine) +
				look.z * (speed.y * speed.z * (1 - cosine) - speed.x * sine);

	newLook.z = look.z * (speed.z * (1 - cosine) +  cosine) + 
				look.y * (speed.y * speed.z * (1 - cosine) + speed.x * sine) +
				look.x * (speed.x * speed.z * (1 - cosine) - speed.y * sine);

	view = position + newLook;
}

I have a feeling that the problem is the second parameter I pass in to the function on the line that doesn't work, but I have no idea I should put there in it's place. However, I could be completly wrong about this, it's just a hunch. Thanks for reading my problem. If you can tell what's wrong, please let me know.

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