#include "SimpleVec.h"
#include <float.h>



// Given min a vector to minimize and a candidate vector, replace
// elements of min whose corresponding elements in Candidate are
// smaller.  This function is used for finding objects' bounds,
// among other things.
void Minimize(SimpleVec &min, const SimpleVec &Candidate)
{
	if (Candidate.x < min.x)
		min.x = Candidate.x;
	if (Candidate.y < min.y)
		min.y = Candidate.y;
	if (Candidate.z < min.z)
		min.z = Candidate.z;
}

// Given min a vector to minimize and a candidate vector, replace
// elements of min whose corresponding elements in Candidate are
// larger.  This function is used for finding objects' bounds,
// among other things.
void Maximize(SimpleVec &max, const SimpleVec &Candidate)
{
	if (Candidate.x > max.x)
		max.x = Candidate.x;
	if (Candidate.y > max.y)
		max.y = Candidate.y;
	if (Candidate.z > max.z)
		max.z = Candidate.z;
}

// Project the vector onto the YZ, XZ, or XY plane depending on which.
// which      Coordinate plane to project onto
// 0          YZ
// 1          XZ
// 2          XY
// This function is used by the polygon intersection code.

void SimpleVec::ExtractVerts(float *px, float *py, int which) const
{
	switch (which) {
	case 0:
		*px = y;
		*py = z;
		break;
	case 1:
		*px = x;
		*py = z;
		break;
	case 2:
		*px = x;
		*py = y;
		break;
	}
}

// returns the axis, where the vector has the largest value
int
SimpleVec::DrivingAxis(void) const
{
	int axis = 0;
	float val = fabs(x);

	if (fabs(y) > val) {
		val = fabs(y);
		axis = 1;
	}

	if (fabs(z) > val)
		axis = 2;

	return axis;
}


// returns the axis, where the vector has the smallest value
int SimpleVec::TinyAxis(void) const
{
	int axis = 0;
	float val = fabs(x);

	if (fabs(y) < val) {
		val = fabs(y);
		axis = 1;
	}

	if (fabs(z) < val)
		axis = 2;

	return axis;
}


bool SimpleVec::CheckValidity() const
{
#ifdef _WIN32
	return !(_isnan(x) || _isnan(y) || _isnan(z));
#else
	return !(isnan(x) || isnan(y) || isnan(z));
#endif  
}