#include "Camera.h"

void InitCamera(VCamera * c)
{
	c->Position.x = 0;
	c->Position.y = 0;
	c->Position.z = 0;
	c->Look.x = 0;
	c->Look.y = 0;
	c->Look.z = -1;
	c->Up.x = 0;
	c->Up.y = 1;
	c->Up.z = 0;
}

void OffsetCamera(VCamera * c, Vector * offset, float interval) {
	c->Position.x += offset->x / interval;
	c->Position.y += offset->y / interval;
	c->Position.z += offset->z / interval;
	
	c->Look.x += offset->x / interval;
	c->Look.y += offset->y / interval;
	c->Look.z += offset->z / interval;
}

void RotateCamera(VCamera * c, Vector * rotate, float interval)
{
	Quaternion QuatView;
	Vector NewRot, Forwards;
	
	NewRot = *rotate;
	NormalizeVector(&NewRot);
	ForwardsVector(c, 1, &Forwards);
	
	QuaternionRotateVector(VectorMagnitude(rotate), interval, &NewRot, 
		&Forwards, &QuatView);
	
	c->Look.x = c->Position.x + QuatView.v.x;
	c->Look.y = c->Position.y + QuatView.v.y;
	c->Look.z = c->Position.z + QuatView.v.z;
	
	QuaternionRotateVector(VectorMagnitude(rotate), interval, &NewRot, 
		&c->Up, &QuatView);
	
	c->Up.x = QuatView.v.x;
	c->Up.y = QuatView.v.y;
	c->Up.z = QuatView.v.z;
	NormalizeVector(&c->Up);
}

void ForwardsVector(VCamera * c, float Distance, Vector * Forwards)
{
	Forwards->x = (c->Look.x - c->Position.x) * Distance;
	Forwards->y = (c->Look.y - c->Position.y) * Distance;
	Forwards->z = (c->Look.z - c->Position.z) * Distance;
}

void ApplyCamera(VCamera * c)
{
	gluLookAt
		(c->Position.x, c->Position.y, c->Position.z, 
		c->Look.x, c->Look.y, c->Look.z, 
		c->Up.x, c->Up.y, c->Up.z);
}