// deformBySurface
// v1.0beta2
// March 6 2000
// Soren 'kurgan' Jacobsen
// kurgan@kurgan.dk  (suggestions/bugreports welcome)
// http://www.kurgan.dk/
//
// History:
// March 6:
// Fixed problems with non-degree 3 deformer surfaces
// **Note!: it is the CV's that are being deformed, that 
// means that fx. deforming a nurbs plane to a sphere
// will only result in the multiknot edge CV's sticking
// to de deformer surface, I havent yet found a way to
// deform the editpoints of a surface, this would fix
// the problem.
// March 5:
// Initial version released
//
// Usage:
// Align the surfaces to be deformed with the X-Z plane
// Select surfaces to deform, 
// and select the surface to deform by last (this _must_ 
// be NURB's surface!!!!
// >deformBySurface <enter>
// now moving the surface in the X-Z plane will move
// them across the surface, moving them i Y will 
// move them to/from the surface.
//
// Description:
// Basic implementation of a function similar to SI's deformbysurface
// and Houdini's pastesurface.
// The deformed surfaces can be moved across the surface
// Construction history is preserved
// The deformer surface can be deformed
// Can be used as a modelling and/or animation tool
//
// Known bugs and limitations:
// No chordlength correction
// Doesnt handle moving across/too close to seams
// 
// Future enhancements:
// -Code cleanup, this script has a lot of 'garbage' code
// because it is a direct dump of my work-in-progress.
// -Chordlength correction
// -I've got an idea to a fix for move across seams
// -A on-surface locator is implemented, but I disabled it
// since 'it doesnt feel right'
// You can enable the codepieces if you like

proc string assembleCmd ()
{
	string $cmd;

	
	$cmd = "doWrapArgList \"2\" { \"1\",";

	float $thresh = `optionVar -query weightThreshold`;
	$cmd = $cmd + "\"" + $thresh + "\",";

	int $limitInfl = `optionVar -q limitInfluence`;
	if ($limitInfl == 1)
		$cmd = $cmd + "\"" + `optionVar -query maxDistance` + "\"";
	else
		$cmd = $cmd + "\"0.0\"";
 
	$cmd = $cmd + " }";
	return $cmd;
}

global proc deformBySurface()
{

// setting up variables etc

 string $sellist[]=`ls -sl`;
 int $numsurfaces = size($sellist) -1;
 string $wrapper = $sellist[$numsurfaces];
 select -tgl $wrapper;
 string $newsellist[]=`ls -sl`;
 select $sellist;

// creating and connecting surfaceInfoNode, so we can access its properties

 string $informationnode = `createNode surfaceInfo`;
 
 string $one = $sellist[$numsurfaces] + ".worldSpace";
 string $two = $informationnode + ".is";
 connectAttr -f $one $two;

// get properties

 float $kulist[] = `getAttr($informationnode + ".ku")`;
 float $kvlist[] = `getAttr($informationnode + ".kv")`;
 int $Uform = getAttr($sellist[$numsurfaces] + ".formU");
 int $Vform = getAttr($sellist[$numsurfaces] + ".formV"); 
 int $Uspans = getAttr($sellist[$numsurfaces] + ".spansU");
 int $Vspans = getAttr($sellist[$numsurfaces] + ".spansV");
 int $Udegree = getAttr($sellist[$numsurfaces] + ".degreeU");
 int $Vdegree = getAttr($sellist[$numsurfaces] + ".degreeV");
 float $UminValue = getAttr($sellist[$numsurfaces] + ".minValueU");
 float $UmaxValue = getAttr($sellist[$numsurfaces] + ".maxValueU");
 float $VminValue = getAttr($sellist[$numsurfaces] + ".minValueV");
 float $VmaxValue = getAttr($sellist[$numsurfaces] + ".maxValueV");

// prepare knotlists

 int $numUpoints = $Uspans + $Udegree;
 int $numVpoints = $Vspans + $Vdegree;
 
 float $kucenteroffset = (float($kulist[0] + $kulist[`size($kulist)`-1]))/2.0;
 float $kvcenteroffset = (float($kvlist[0] + $kvlist[`size($kvlist)`-1]))/2.0;

// the following is for on-surface locator
// float $kucenteroffset = 0;
// float $kvcenteroffset = 0;
// on-surface locator end
 float $kucenteroffset = (float($numUpoints-1.0)/2)+$Udegree-1;
 float $kvcenteroffset = (float($numVpoints-1.0)/2)+$Vdegree-1;

 string $skvlist=" ";  
 for ($n in $kvlist)
  {
       $skvlist += " -kv " + $n;
  }

 string $skulist=" ";  
 for ($n in $kulist)
  {
       $skulist += " -ku " + $n;
  }

// prepare pointlist

 string $pointlist=" ";
// for ($nu=$Udegree-2;$nu<($numUpoints+$Udegree-2);$nu++)
 for ($nu=$Udegree-1;$nu<($numUpoints+$Udegree-1);$nu++)
  {

//    for ($nv=($numVpoints+$Vdegree-3);$nv>$Vdegree-3;$nv--)
    for ($nv=$Vdegree-1;$nv<($numVpoints+$Vdegree-1);$nv++)
     {
//       $pointlist += " -p " + float(-$kucenteroffset+$kulist[$nu]) + " " + 0 +" "+ float(-$kvcenteroffset+$kvlist[$nv]);
       $pointlist += " -p " + (float($nu)-$kucenteroffset) + " " + 0 +" "+ ($kvcenteroffset - float($nv));
     }

  }

// create the base (undeformed) surface

 string $formHolder[] = {"open", "closed", "periodic"};
 string $mycommand = "surface -degreeU " + $Udegree + " -degreeV " + $Vdegree + " -formU " + $formHolder[0] + " -formV " + $formHolder[0] + $pointlist + $skulist + $skvlist;
 string $newdeformsurf = eval($mycommand);
 setAttr ($newdeformsurf + ".intermediateObject") 1;
 
// we no longer need the surfaceInfoNode, get rid of it

 delete $informationnode;

// do the deformation(s)

for ($wrp in $newsellist)
  {
   select -r $wrp;
   select -add $wrapper;
   string $doWrap = `assembleCmd`;
   string $wraplst[] = `eval($doWrap)`;
   string $wrap = $wraplst[0];
   string $tmp1 = $newdeformsurf + ".worldSpace[0]";
   string $tmp2 = $wrap + ".basePoints[0]";
   connectAttr -f $tmp1 $tmp2;

// the following is for on-surface locator
// string $curveOnsurf = curveOnSurface -d 2 -uv 0.0 0.0 -k 0 -k 0 $wrapper ;
// sting $expressionString = $wrp + ".translateX=" + $curveOnsurf + ".translateX;\n" + $wrp + ".translateZ=" + $curveOnsurf + ".translateY;";
// expression -s $expressionString  -o $wrp -ae 1 -uc all ;
// on-surface locator end

  }

 
}