void Camera::RotateView(float angle, float x, float y, float z)	{		Vector3f vNewView;				// Get the view vector (The direction we are facing)		Vector3f vView = _lookAt - _position;						// Calculate the sine and cosine of the angle once		float cosTheta = (float)cos(angle);		float sinTheta = (float)sin(angle);				// Find the new x position for the new rotated point		vNewView[0]  = (cosTheta + (1 - cosTheta) * x * x)		* vView[0];		vNewView[0] += ((1 - cosTheta) * x * y - z * sinTheta)	* vView[1];		vNewView[0] += ((1 - cosTheta) * x * z + y * sinTheta)	* vView[2];				// Find the new y position for the new rotated point		vNewView[1]  = ((1 - cosTheta) * x * y + z * sinTheta)	* vView[0];		vNewView[1] += (cosTheta + (1 - cosTheta) * y * y)		* vView[1];		vNewView[1] += ((1 - cosTheta) * y * z - x * sinTheta)	* vView[2];				// Find the new z position for the new rotated point		vNewView[2]  = ((1 - cosTheta) * x * z - y * sinTheta)	* vView[0];		vNewView[2] += ((1 - cosTheta) * y * z + x * sinTheta)	* vView[1];		vNewView[2] += (cosTheta + (1 - cosTheta) * z * z)		* vView[2];				// Now we just add the newly rotated vector to our position to set		// our new rotated view of our camera.		_lookAt = _position + vNewView;	}void Camera::onMousePassiveMotion(int x, int y) 	{		int middleX = (int)_winWidth  >> 1;				// This is a binary shift to get half the width		int middleY = (int)_winHeight >> 1;				// This is a binary shift to get half the height		float angleY = 0.0f;							// This is the direction for looking up or down		float angleZ = 0.0f;							// This will be the value we need to rotate around the Y axis (Left and Right)		static float currentRotX = 0.0f;				// If our cursor is still in the middle, we never moved... so don't update the screen		if( (x == middleX) && (y == middleY) ) return;				// Set the mouse position to the middle of our window		glutWarpPointer(middleX, middleY);										// Get the direction the mouse moved in, but bring the number down to a reasonable amount		angleY = (float)( (middleX - x) ) / 500.0f;				angleZ = (float)( (middleY - y) ) / 500.0f;						// Here we keep track of the current rotation (for up and down) so that		// we can restrict the camera from doing a full 360 loop.		currentRotX -= angleZ;  				// If the current rotation (in radians) is greater than 1.0, we want to cap it.		if(currentRotX > 1.0f)			currentRotX = 1.0f;		// Check if the rotation is below -1.0, if so we want to make sure it doesn't continue		else if(currentRotX < -1.0f)			currentRotX = -1.0f;		// Otherwise, we can rotate the view around our position		else		{			// To find the axis we need to rotate around for up and down			// movements, we need to get a perpendicular vector from the			// camera's view vector and up vector.  This will be the axis.			Vector3f vAxis = cross(_lookAt - _position, _up);			vAxis = normalize(vAxis);						// Rotate around our perpendicular axis and along the y-axis			RotateView(angleZ, vAxis[0], vAxis[1], vAxis[2]);		}				// Rotate around the y axis no matter what the currentRotX is		RotateView(angleY, 0, 1, 0);	}