tvector.cpp

关于OpenGL的实例教程源代码

/*******************************************************************************/
/*********************************21/09/200*************************************/
/**********************Programmer: Dimitrios Christopoulos**********************/
/**********************for the oglchallenge contest*****************************/
/**********************COLLISION CRAZY******************************************/
/*******************************************************************************/

#include "tvector.h"

#include "tray.h"



// Mid point between two rays

TVector::TVector(const TRay &ray1, const TRay &ray2) {

	TVector point1, point2;

	if (ray1.adjacentPoints(ray2, point1, point2))

		*this = (point1 + point2)*0.5;

	else

		*this = TVector();

}



// Make a unit vector

TVector &TVector::unit() {

	if (isDefault()) {

		double rep = mag();

		if (rep < EPSILON) {

			_x = 0.0;

			_y = 0.0;

			_z = 0.0;

		} else {

			double temp = 1.0 / rep;

			_x *= temp;

			_y *= temp;

			_z *= temp;

		}

		_Status = UNIT;

	}

	return *this;

}



// Make a default vector

TVector &TVector::Default() {

	if (isUnit())

		_Status = DEFAULT;

	return *this;

}



TVector &TVector::invert(const TVector &v1, TVector &result) {

	if (v1.isValid()) {

		result._x = -v1._x;

		result._y = -v1._y;

		result._z = -v1._z;

		result._Status = v1._Status;

	} else

		result = TVector();

	return result;

}



TVector &TVector::add(const TVector &v1, const TVector &v2, TVector &result) {

	if (v1.isValid() && v2.isValid()) {

		result._x = v1._x + v2._x;

		result._y = v1._y + v2._y;

		result._z = v1._z + v2._z;

		result._Status = DEFAULT;

	} else

		result = TVector();

	return result;

}



TVector &TVector::subtract(const TVector &v1, const TVector &v2, TVector &result) {

	if (v1.isValid() && v2.isValid()) {

		result._x = v1._x - v2._x;

		result._y = v1._y - v2._y;

		result._z = v1._z - v2._z;

		result._Status = DEFAULT;

	} else

		result = TVector();

	return result;

}



TVector &TVector::cross(const TVector &v1, const TVector &v2, TVector &result) {

	if (v1.isValid() && v2.isValid()) {

		result._x = v1._y * v2._z - v1._z * v2._y;

		result._y = v1._z * v2._x - v1._x * v2._z;

		result._z = v1._x * v2._y - v1._y * v2._x;

		result._Status = DEFAULT;

	} else

		result = TVector();

	return result;

}



TVector &TVector::multiply(const TVector &v1, const double &scale, TVector &result) {

	if (v1.isValid()) {

		result._x = v1._x * scale;

		result._y = v1._y * scale;

		result._z = v1._z * scale;

		result._Status = DEFAULT;

	} else

		result = TVector();

	return result;

}



// Streaming

ostream &TVector::write(ostream &out) const {

	if (isValid())

		if (isUnit())

			return out<<"<"<<X()<<","<<Y()<<","<<Z()<<">";

		else

			return out<<"["<<X()<<","<<Y()<<","<<Z()<<"]";

	return out<<"Invalid";

}



istream &TVector::read(istream &in) {

	char buf[20],ch, ch2;

	in >> ch2;

	if (ch2 != 'I') {

		double x,y,z;

		in >> x >> ch >> y >> ch >> z;

		*this=TVector(x,y,z);

		if (ch2 == '<')

			unit();

	} else {

		*this=TVector();

		in.get(buf,20,'d');

	}

	return in >> ch;

}