// Camera.cpp: implementation of the CCamera class.
//
//////////////////////////////////////////////////////////////////////

#include "Camera.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////


CCamera::CCamera():CObjectInScene()
{
	Type=CAMERA;
	Name="camera";
	Visible=true;
	Selected=false;
	NormalColor[0]=0.0;
	NormalColor[0]=0.8;
	NormalColor[0]=0.8;
	Eye[0]=0.0;Eye[1]=0.0;Eye[2]=0.0;
	At[0]=0.0;At[1]=0.0;At[2]=-1.0;
	Up[0]=0.0;Up[1]=1.0;Up[2]=0.0;
}

CCamera::~CCamera()
{

}
void CCamera::readProperty(FILE *fp)
{
	int i;
	char s[81];
	float x0,x1,x2;
	i = fseek( fp, 0L, SEEK_SET);
    if( i ) printf( "Fseek failed");

	do {
		fscanf( fp, "%s", s );
		i=strcmp( s,Name); 
	}while(!feof(fp) && i!=0);
	if(!feof(fp)){
		fscanf(fp,"%s\t%f\n",s,&x0);
		fscanf(fp,"%s\t%f\n",s,&x1);
		fscanf(fp,"%s\t%f\n",s,&x2);
		Fov=x0;Near=x1;Far=x2;
		fscanf(fp,"%s\t%f,%f,%f\n",s,&x0,&x1,&x2);
		//Eye[0]=x0;Eye[1]=x1;Eye[2]=x2;
		TMatrix[12]=x0;TMatrix[13]=x1;TMatrix[14]=x2;
		fscanf(fp,"%s\t%f,%f,%f\n",s,&x0,&x1,&x2);
		At[0]=x0;At[1]=x1;At[2]=x2;
		fscanf(fp,"%s\t%f,%f,%f\n",s,&x0,&x1,&x2);
		Up[0]=x0;Up[1]=x1;Up[2]=x2;
	}
}

void CCamera::writeProperty(FILE *fp)
{
	fprintf(fp, "%s\t%s\n","Name:", Name);
	fprintf(fp, "%s\t%f\n","Fov:", Fov);
	fprintf(fp, "%s\t%f\n","Near:", Near);
	fprintf(fp, "%s\t%f\n","Far:", Far);
	//fprintf(fp, "%s\t%f,%f,%f\n","Eye:", Eye[0],Eye[1],Eye[2]);
	fprintf(fp, "%s\t%f,%f,%f\n","Eye:", TMatrix[12],TMatrix[13],TMatrix[14]);
	fprintf(fp, "%s\t%f,%f,%f\n","At:", At[0],At[1],At[2]);
	fprintf(fp, "%s\t%f,%f,%f\n\n","Up:", Up[0],Up[1],Up[2]);
}

void CCamera::render()
{
	float p[3],n[3],v[3],u[3];
	float s,t;
	int i;

	if (isSelected())
		glColor3fv(HighlightColor);
	else
		glColor3fv(NormalColor);
	GLUquadric* quad=gluNewQuadric();
	GLdouble radius=0.3;
	GLint slices=10;
	GLint stacks=10;
	gluSphere(quad, radius,slices,stacks);
//calculate n,v,v 
	for(i=0;i<3;i++) p[i]=TMatrix[12+i];
	for(i=0;i<3;i++) n[i]=At[i]-p[i];
	
	s=Up[0]*n[0]+Up[1]*n[1]+Up[2]*n[2];
	t=n[0]*n[0]+n[1]*n[1]+n[2]*n[2];
	s=s/t;
	for(i=0;i<3;i++) v[i]=Up[i]-s*n[i];
	s=v[0]*v[0]+v[1]*v[1]+v[2]*v[2];
	s=sqrt(s);
	
	t=sqrt(t);
	if (t==0) printf("Error: Eye and At cann't be the save point!\n");
	else {
		for(i=0;i<3;i++){
	 		n[i]/=t;
			v[i]/=s;
		}
	}
	u[0]=v[1]*n[2]-v[2]*n[1];
	u[1]=v[2]*n[0]-v[0]*n[2];
	u[2]=v[0]*n[1]-v[1]*n[0];
//draw n,v,u
	glBegin(GL_LINES);
		glColor3f(1.0, 0.0, 0.0);
		glVertex3d(0.0,0.0,0.0);
		glVertex3d(3*u[0],3*u[1],3*u[2]);
	
		glColor3f(0.0, 1.0, 0.0);
		glVertex3d(0.0,0.0,0.0);
		glVertex3d(3*v[0],3*v[1],3*v[2]);

		glColor3f(0.0, 0.0, 1.0);
		glVertex3d(0.0,0.0,0.0);
		glVertex3d(3*n[0],3*n[1],3*n[2]);
	glEnd();

}