code snippet - is node or cachedGeom vertex - inside oriented box

mCasualmCasual Posts: 4,030

who knows maybe someday someone will see it and later remember it's here

the idea is we take the world-space vertex position,
apply the inverse of the transform of the oriented bounding box
then we check if that position is in the oriented bounding box's ''local bounding box"

to test this
-create a little ball and a cube
-animate the ball over 30 frames going in and out of the cube
-select a little ball, then select a rotated/translated cube
-run the script

the script will make the ball small when it's outside, and larger when it's inside

var node = Scene.getSelectedNode( 0 );
var cube = Scene.getSelectedNode( 1 )
var scaler = node.getScaleControl();
var tick = Scene.getTimeStep();
for( i = 0; i <= 30; i++ )
{ 
 var t = i * tick;
 var dOBB = cube.getWSOrientedBox( t );
 var dLBox = dOBB.localBox;
 var dTrans = dOBB.transform ;
 var dUnTrans = dTrans.inverse(); 
 var bInBox = inBox( node.getWSPos( t ), dLBox, dUnTrans );
 if( bInBox ) 
  scaler.setValue( t, 1 );
 else
  scaler.setValue( t, .5 );
}

function inBox( v, bb, dUnTrans )
{  
 var vv = dUnTrans.multMatrixVec( v );
 if( ( vv.x > bb.minX ) && ( vv.x < bb.maxX ) )
 {
  if( ( vv.y > bb.minY ) && ( vv.y < bb.maxY ) )
  {
   if( ( vv.z > bb.minZ ) && ( vv.z < bb.maxZ ) )
   {
    return( true );
   }
  }
 }
 return( false );
}
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Post edited by mCasual on

Comments

  • TugpsxTugpsx Posts: 209
    edited December 1969

    Wow thanks, that's a neat way to address the issue

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