/*
begin

 jf_downAxis.mel
Jean-Francois Fortin

-=WHAT IT DOES=-
	will return which axis your joint is pointing.
	doesnt work if axis is pointing negative.

-=RETURN=-
	<<0,10>>

-=EXAMPLES=-


-=REQUIRES=-
	-=NONE=-

-=UPDATES=-


end
*/
////
global proc vector jf_downAxis()
{
	float $cx;
	float $sx;
	float $cy;
	float $sy;
	float $cz;
	float $sz;

	float $ox;
	float $ux;
	float $oy;
	float $uy;
	float $oz;
	float $uz;

	float $angles[];
	float $pi = 3.14159265;

	matrix $rotT[4][4];
	matrix $oriT[4][4];
	matrix $total[4][4];

	vector $dd;
	vector $pPoss;
	vector $cPoss;

	string $joints[] = `ls -sl -typ joint`;
	string $child[] = `listRelatives -c -typ joint $joints[0]`;
	string $parent[] = `listRelatives -p -typ joint $joints[0]`;


	if( `size($parent)` )
	{
		parent -w $joints[0];
		$angles = `joint -q -o $joints[0]`;
		parent $joints[0] $parent[0];
	}
	else
	{
		$angles = `joint -q -o $joints[0]`;
	}

	if(  !`size($child[0])` &&`size($parent[0])` )
	{
		$pPoss = `xform -q -ws -a -t $joints[0]`;
		$cPoss = `xform -q -ws -a -t $parent[0]`;
		$dd = $pPoss - $cPoss;
	}
	else
	{
		$pPoss = `xform -q -ws -a -t $joints[0]`;
		$cPoss = `xform -q -ws -a -t $child[0]`;
		$dd = $cPoss - $pPoss;
	}

	float $rotX = `getAttr ( $joints[0]+".rotateX")`;
	float $rotY = `getAttr ( $joints[0]+".rotateY")`;
	float $rotZ = `getAttr ( $joints[0]+".rotateZ")`;

	$cx = cos( $angles[0]*$pi/180 );
	$sx = sin( $angles[0]*$pi/180 );

	$cy = cos( $angles[1]*$pi/180 );
	$sy = sin( $angles[1]*$pi/180 );

	$cz = cos( $angles[2]*$pi/180 );
	$sz = sin( $angles[2]*$pi/180 );

	$ox = cos( $rotX *$pi/180 );
	$ux = sin( $rotX *$pi/180 );

	$oy = cos( $rotY*$pi/180 );
	$uy = sin( $rotY*$pi/180 );

	$oz = cos( $rotZ*$pi/180 );
	$uz = sin( $rotZ*$pi/180 );

	matrix $ojx[4][4] = <<1,0,0,0;
			0,$cx,($sx*-1),0;
			0,$sx,$cx,0;
			0,0,0,1>>;

	matrix $ojy[4][4] = <<$cy,0,$sy,0;
			0,1,0,0;
			($sy*-1),0,$cy,0;
			0,0,0,1>>;

	matrix $ojz[4][4] = <<$cz,($sz*-1),0,0;
			$sz,$cz,0,0;
			0,0,1,0;
			0,0,0,1>>;


	matrix $rox[4][4] = <<1,0,0,0;
			0,$ox,($ux*-1),0;
			0,$ux,$ox,0;
			0,0,0,1>>;

	matrix $roy[4][4] = <<$oy,0,$uy,0;
			0,1,0,0;
			($uy*-1),0,$oy,0;
			0,0,0,1>>;

	matrix $roz[4][4] = <<$oz,($uz*-1),0,0;
			$uz,$oz,0,0;
			0,0,1,0;
			0,0,0,1>>;

	$rotT = $roz*$roy*$rox;
	$oriT = $ojz*$ojy*$ojx;

	$total = $oriT*$rotT;

	matrix $x[4][1] = <<1;0;0;1>>;
	matrix $y[4][1] = <<0;1;0;1>>;
	matrix $z[4][1] = <<0;0;1;1>>;

	matrix $xT[4][1] = $total*$x;
	matrix $yT[4][1] = $total*$y;
	matrix $zT[4][1] = $total*$z;

	vector $vxT = << $xT[0][0],$xT[1][0],$xT[2][0] >>;
	vector $vyT = << $yT[0][0],$yT[1][0],$yT[2][0] >>;
	vector $vzT = << $zT[0][0],$zT[1][0],$zT[2][0] >>;

	vector $lx = sqrt($dd.x*$dd.x+$dd.y*$dd.y+$dd.z*$dd.z);

	vector $lxa = sqrt($vxT.x*$vxT.x+$vxT.y*$vxT.y+$vxT.z*$vxT.z);
	vector $lya = sqrt($vyT.x*$vyT.x+$vyT.y*$vyT.y+$vyT.z*$vyT.z);
	vector $lza = sqrt($vzT.x*$vzT.x+$vzT.y*$vzT.y+$vzT.z*$vzT.z);

	$dd = $dd/$lx;

	$vxT = $vxT/$lxa;
	$vyT = $vyT/$lxa;
	$vzT = $vzT/$lxa;

	float  $dotx = dot( $dd,$vxT );
	float  $doty = dot( $dd,$vyT );
	float  $dotz = dot( $dd,$vzT );

	if( $dotx > 0.99 )
	{
		return <<1,0,0>>;
	}

	else if( $doty > 0.99 )
	{
		return <<0,1,0>>;
	}

	else if( $dotz > 0.99 )
	{
		return <<0,0,1>>;
	}
	else
	{
		return "none";
	}
}