// getFaceNormals by kbrown
//
proc vector[] getFaceNormals(string $sPolyObject)
{
	vector $vNormals[];
	int $i;

	// get all face normals in to a string array
	string $sFaceNormals[] = `polyInfo -fn $sPolyObject`;
	
	// parse the string array and create a vector array holding the normal info
	for($i = 0; $i < size($sFaceNormals); $i++)
	{
		string $sBuffer[];
		tokenize($sFaceNormals[$i], $sBuffer);
		float $fX = $sBuffer[2];
		float $fY = $sBuffer[3];
		float $fZ = $sBuffer[4];
		$vNormals[$i] = <<$fX, $fY, $fZ>>;
	}
	
	// free some memory
	clear($sFaceNormals);
	
	// return the vector array
	return $vNormals;
}

 // Copyright (C) 1997-2004 Alias Systems Corp.
// 
// The information in this file is provided for the exclusive use of the
// licensees of Alias.  Such users have the right to use, modify,
// and incorporate this code into other products for purposes authorized
// by the Alias license agreement, without fee.
// 
// ALIAS DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
// INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO
// EVENT SHALL ALIAS BE LIABLE FOR ANY SPECIAL, INDIRECT OR
// CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE,
// DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER
// TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
// PERFORMANCE OF THIS SOFTWARE.
//
// authors: afuchs and rreyer
//
// Version 23.12.04 - 13:55
//
//
//

proc copyTRS( string $source, string $dest)
{
	float $v[] = `getAttr ($source + ".translate")`;
	setAttr -type double3 ($dest + ".translate") ($v[0]) ($v[1]) ($v[2]);
	float $v[] = `getAttr ($source + ".rotate")`;
	setAttr -type double3 ($dest + ".rotate") ($v[0]) ($v[1]) ($v[2]);
	float $v[] = `getAttr ($source + ".scale")`;
	setAttr -type double3 ($dest + ".scale") ($v[0]) ($v[1]) ($v[2]);
}

global proc normalChecker( )
{
	
		string $selection[] = `ls-sl`;

		string $shapes[];
		string $inverse[];
	
		$shapes = `ls -v -ni -ut -sl -dag -type nurbsSurface -type mesh`;
		
	if (size($shapes)) {			// create red inverse surfaces
	
		string $inverseShadingGroup;
		if (!`objExists "normalCheckRedShader"`) {
			$inverseShader = `shadingNode -name "normalCheckRedShader" -asShader lambert`;
			setAttr ($inverseShader +".color") -type double3 1 0 0 ;
			$inverseShadingGroup =`sets -renderable true -noSurfaceShader true -empty -name ($inverseShader +"SG")`;
			connectAttr -f ($inverseShader + ".outColor") ($inverseShadingGroup + ".surfaceShader");
		} else $inverseShadingGroup = "normalCheckRedShaderSG";
	
		if (!`objExists "normalCheckLayer"`) {
			createDisplayLayer -name "normalCheckLayer" -number 1 -empty;
			setAttr normalCheckLayer.displayType 2;
		}
	
	
	
		for ( $obj in $shapes ) 
		{
			// check, if this shape is connected to the inverseLayer (that means, it is an inverse)
			if (!`isConnected normalCheckLayer.drawInfo ($obj + ".drawOverride")`) {
				string $tmp[] = `listRelatives -p $obj`;
				string $parent = $tmp[0];

				string $inverse;
				if ( `objectType $obj` == "nurbsSurface" ) 
				{
					// first check, if an inverse already exists
					if (!`objExists ($obj + "_inverse")` || !`isConnected ($obj + ".worldSpace[0]") ($obj + "_inverse.create")`) {

						$inverse =`createNode -n ($obj + "_inverse") nurbsSurface`;
//						$inverse =`createNode -p $parent -n ($obj + "_inverse") nurbsSurface`;
						connectAttr -f ($obj+ ".worldSpace[0]") ($inverse +".create");
					}
				} else {
					// first check, if an inverse already exists
					if (!`objExists ($obj + "_inverse")` || !`isConnected ($obj + ".outMesh") ($obj + "_inverse.inMesh")`) {

						$inverse =`createNode -n ($obj + "_inverse") mesh`;
//						$inverse =`createNode -p $parent -n ($obj + "_inverse") mesh`;
						connectAttr -f ($obj + ".outMesh") ($inverse + ".inMesh");
					}
				}

				// do we have a new inverse?
				if (size($inverse)) {

					string $tmp[] = `listRelatives -p $inverse`;
					string $inverseParent = $tmp[0];
					copyTRS( $parent, $inverseParent);

					select $inverseParent;
					layerEditorAddObjects normalCheckLayer;

					// now set the new shape to be reverse (from whatever the orig ist)
					setAttr ($obj + ".doubleSided") 0;
					setAttr ($inverse + ".doubleSided") 0;

					// set the opposite flag for the single side option
					setAttr ($inverse + ".opposite") (!`getAttr ($obj + ".opposite")`);

					// connecting it to the red shader
					select -r $inverse;
					sets -e -forceElement $inverseShadingGroup;
				}
			}
		}

	} else {			// delete red inverse surfaces, the layer and the red shader
		if (`objExists "normalCheckLayer"`) {
			layerEditorSelectObjects normalCheckLayer;

			// set the original shapes back to "doublesided"
			string $shapes[] = `ls -v -ni -ut -sl -dag -type nurbsSurface -type mesh`;
			for ( $s in $shapes ) {
				string $tmp[];
				if ( `objectType $s` == "nurbsSurface" ) $tmp = `listConnections -s 1 -p 0 -sh 1 ($s + ".create")`;
				else $tmp = `listConnections -s 1 -p 0 -sh 1 ($s + ".inMesh")`;
				setAttr ($tmp[0] + ".doubleSided") 1;
			}

			if (size(`ls -sl`)) delete;
			evalDeferred ("layerEditorDeleteLayer normalCheckLayer");
		}

		if (`objExists "normalCheckRedShader"`) {
			string $tmp[] = `listConnections -d 1 "normalCheckRedShader.outColor"`;
			$tmp = `ls -type shadingEngine $tmp`;
			if (size($tmp)) delete $tmp;
			delete normalCheckRedShader;
		}
	}

	select -r $selection;

}