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OpenGL NEED HELP: Spherical Camera Class :: Spherical Coordinates

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justinrwalsh    171
I am working an a spherical camera class for OpenGL. I have the calculations but i think i am still doing it wrong. All i want to do is have a camera somwhere in 3d space always looking at point 0,0,0, that rotates about a sphere. here is what i have. SphericalCamera.h

#include "windows.h"
#include <math.h>
#include "GL/gl.h"
#include "GL/glu.h"
#include "SDL.h"

#define pi 3.14159265358979f

struct Vector3f{
	float x;
	float y;
	float z;

class SphericalCamera  {
		SphericalCamera(float eyeX, float eyeY, float eyeZ);

		void UpdateView(void);
		void RotateY(float degrees);
		void RotateZ(float degrees);


		void CartesianToSpherical(void);				//Convert from Cartesian To Spherical.
		void SphericalToCartesian(void);				//Convert from Spherical To Cartesian.

		void CalcRadius(void);	//				These functions may be needed to calculate things we yet do not know.
		void CalcTheta(void);	//				...
		void CalcPhi(void);		//				...

		float RadtoDeg(float x);
		float DegToRad(float x);

        float theta;			//				0 to pi (radians) (180 degrees)
		float phi;				//				rotation in x/y plane
		float radius;			//				Radius or distance from point of origin

		Vector3f eye;    		//				The current position in 3d space of the eye 
								//				using Cartesian coordinates
		Vector3f center;		//				The center of the scene, or what we are looking at
		Vector3f upVector;		//				Current Up Vector

		Vector3f eyeOrigin;		//				Camera's eye Point of origin
		Vector3f centerOrigin;	//				Center of scene point of origin
		Vector3f upOrigin;		//				The original Up Vector


#include "SphericalCamera.h"

SphericalCamera::SphericalCamera(float eyeX, float eyeY, float eyeZ)
	SphericalCamera::centerOrigin.x = 0.0f;
	SphericalCamera::centerOrigin.y = 0.0f;
	SphericalCamera::centerOrigin.z = 0.0f;
	SphericalCamera::center = centerOrigin;

	SphericalCamera::eyeOrigin.x = eyeX;
	SphericalCamera::eyeOrigin.y = eyeY;
	SphericalCamera::eyeOrigin.z = eyeZ;
	SphericalCamera::eye = eyeOrigin;

	SphericalCamera::upOrigin.x = 0.0f;
	SphericalCamera::upOrigin.y = 1.0f;
	SphericalCamera::upOrigin.z = 0.0f;
	SphericalCamera::upVector = upOrigin;


SphericalCamera::~SphericalCamera(void)  {

void SphericalCamera::CartesianToSpherical(void)  {
	eye.x = radius;
	eye.y = theta;
	eye.z = phi;
	eye.y = SphericalCamera::RadtoDeg(eye.y);
	eye.z = SphericalCamera::RadtoDeg(eye.z);

void SphericalCamera::SphericalToCartesian(void)  {
	eye.x = radius * sin(theta) * cos(phi);
	eye.y = radius * sin(theta) * sin(phi);
    eye.z = radius * cos(theta);
	eye.y = SphericalCamera::DegToRad(eye.y);
	eye.z = SphericalCamera::DegToRad(eye.z);

void SphericalCamera::CalcRadius(void)  {
	radius = sqrt((pow(eye.x,2) + pow(eye.y,2) + pow(eye.z,2)) );

void SphericalCamera::CalcTheta(void)  {
	theta = acos(eye.x / radius);

void SphericalCamera::CalcPhi(void)  {
	phi = acos( eye.x /(radius * sin(theta) ) );

float SphericalCamera::RadtoDeg(float x)  {
	return x * 180.0f / pi;

float SphericalCamera::DegToRad(float x)  {
	return x * pi / 180.0f;

void SphericalCamera::RotateY(float degrees)  {
	theta += degrees;

void SphericalCamera::RotateZ(float degrees)  {
	phi += degrees;

void SphericalCamera::UpdateView(void)  {

	center.x = centerOrigin.x - eye.x;
	center.y = centerOrigin.y - eye.y;
	center.z = centerOrigin.z - eye.z;
	float length;

	length = sqrt(pow(center.x, 2) + pow(center.y, 2) + pow(center.z, 2));

	center.x /= length;
	center.y /= length;
	center.z /= length;

	gluLookAt(eye.x, eye.y, eye.z, center.x, center.y, center.z, upVector.x, upVector.y, upVector.z);

Now the problem lies in the converison i think, if i feed it 0,0,10 (x,y,z) after all the convertions i dont even get numbers back that are close to 0,0,10 i get like -2.5044781e-006, 1.0000000,-4.3711388e-008 after a convertion from spherical to cartesian. Can someone hlp me figure out where my convertions are going wrong? thanks guys i've been hung up on this for a long time now.

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