/*
<?xml version='1.0' standalone='yes' ?>
<!-- xml header for scripts & plugin manager --> 
<script>
	<name>Tinsel</name>
	<author>François Guillet (fpgui@users.sourceforge.net)</author>
	<version>1.9</version>
	<date>27/04/2004</date>
	<description>
This script decorates a tube object with a one or several object(s) at each of its vertices. The objects used
for decoration can be single AoI objects or groups of objects.  
It can be used to place lights along a wire or make a christmas tree tinsel -hence the script name-.
    </description>
</script>
*/


if ( script.isPreview() )
	return;
//If randomize  is true the object is chosen at random form a pool of objects.
//if false objects are placed in sequence, one after the other
boolean randomize = true;
//The random sequence depends on the seed used.
Random rand = new Random( 12369878);
//initialize random sequence
for (int i = 0; i < 12; i++ )
    rand.nextDouble();
scene = script.getScene();
//the tube object and its transformation matrix. Use another name if you wish
Tube t =  (Tube) (scene.getObject("Tinsel").object);
Mat4 m = scene.getObject("Tinsel").coords.fromLocal();
//the tube vertices
Vec3[] orv = t.getVertexPositions();
int count = orv.length;
Vec3[] v = new Vec3[ orv.length ];
//increase step if you want to place an object each n vertex instead of each vertex
int step = 1;

//Decorators information
//groups represent groups of objects that are placed on the tube
//groups need not have the same number of objects. The example below consists of two groups
//The first group consists of two objects
//The second group is a single object.
//When a group coordinates are calculated, every object is placed relative to the first object, which acts
//as origin of the group. If need be, placing a null object as first object of a group
//can help group placement.
//Groups are rotated 90° away from the tube axis, and 0<rotation<360° randomly
//in the plane perpendicular to the tube axis.
//Any object created is a live duplicate.
ObjectInfo[][] groups = { { scene.getObject("Tinsel_1_1"), scene.getObject("Tinsel_1_2") },
 													{ scene.getObject("Tinsel_2_1") } };
int groupsNumber = groups.length; 

for (int i = 0; i < count; i++ )
    v[i] = m.times( orv[i] );
int randNum = 0;
//tube extremities are not decorated (from 1 to count-1)
for (int i = 1; i < count-1; i+=step )
{
    if ( randomize )
        randNum = rand.nextInt( groupsNumber );
    else
    {
        ++randNum;
        if (randNum >= groupsNumber)
            randNum = 0;
    }
    //duplicates creation.
    ObjectInfo[] infos= new ObjectInfo[ groups[randNum].length] ;
    for (int k = 0; k < groups[randNum].length; ++k )
        infos[ k ] = groups[randNum][k].duplicate();
    
    //translation to origin, for convenience
    Vec3 trans = new Vec3().minus( infos[0].coords.getOrigin() );
    Mat4 m = Mat4.translation( trans.x, trans.y, trans.z );
    for (int k = 0; k < groups[randNum].length; ++k )
        infos[k].coords.transformCoordinates( m );

    //random in plane rotation
    Mat4 orient = Mat4.yrotation( rand.nextDouble() * 2 * Math.PI );
    orient = orient.times( Mat4.zrotation( Math.PI/2 ) );
    for (int k = 0; k < groups[randNum].length; ++k )
        infos[k].coords.transformCoordinates( orient );
    
    //90° rotation away from tube Y axis
    Vec3 tangent = v[i+1].minus( v[i-1] );
    tangent.normalize();
    Vec3 yVec = new Vec3( 0, 1, 0 );
    Vec3 axis = yVec.cross( tangent );
    double matAngle = Math.acos( yVec.dot( tangent ) );
    Mat4 nm = Mat4.axisRotation( axis, matAngle );
    //translation to relevant tube vertex
    Mat4 result = Mat4.translation( v[i].x, v[i].y, v[i].z );
    result = result.times( nm );
    for (int k = 0; k < groups[randNum].length; ++k )
    {
        infos[k].coords.transformCoordinates( result );
        script.addObject( infos[k] );
    }
}