//-
// ==========================================================================
// Copyright (C) 1995 - 2005 Alias Systems Corp. and/or its licensors.  All 
// rights reserved. 
// 
// The coded instructions, statements, computer programs, and/or related 
// material (collectively the "Data") in these files are provided by Alias 
// Systems Corp. ("Alias") and/or its licensors for the exclusive use of the 
// Customer (as defined in the Alias Software License Agreement that 
// accompanies this Alias software). Such Customer has the right to use, 
// modify, and incorporate the Data into other products and to distribute such 
// products for use by end-users.
//  
// THE DATA IS PROVIDED "AS IS".  ALIAS HEREBY DISCLAIMS ALL WARRANTIES 
// RELATING TO THE DATA, INCLUDING, WITHOUT LIMITATION, ANY AND ALL EXPRESS OR 
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// ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, OR IN EQUITY, 
// ARISING OUT OF ACCESS TO, USE OF, OR RELIANCE UPON THE DATA.
// ==========================================================================
//+


// MAYA HEADERS

#include <maya/MFnPlugin.h>

#include <maya/MDagPath.h>

#include <maya/MFnMesh.h>

#include <maya/MItSelectionList.h>

#include <maya/MItMeshPolygon.h>

#include <maya/MObject.h>

#include <maya/MSelectionList.h>

#include <maya/MArgList.h>

#include <maya/MFloatPoint.h>

#include <maya/MFnDependencyNode.h>

#include <maya/MFnSpotLight.h>

#include <maya/MFloatPointArray.h>

#include <maya/MPxCommand.h>

#include <maya/MDGModifier.h>

#include <maya/MFnDagNode.h>

#include <maya/MDagPath.h>

#include <maya/MGlobal.h>



#ifndef INTERSECTCMD

#define INTERSECTCMD



#define MERR_CHK(stat,msg) if ( !stat ) { MGlobal::displayError(msg); } // cerr << msg << endl; }



/////////////////////////////////////////////////////////////////////////////////////////////////

//

//	PLUGIN DESCRIPTION

//	

//	This is an example of finding the intersection points on a mesh from a spotlight using the 			//	intersection acceleration methods in MFnMesh.

//	

//

//	PLUGIN INSTRUCTIONS

//

//	- create a spotlight and a poly plane (mesh)

//	- orient the light to shine onto the plane

//	- run the command as such: intersectCmd <spotLightName> <planeName>

//	- if there is an intersection, a small sphere will be created at the intersection point.

//	

//	Use the following script to automatically display intersections on the mesh (assuming 

//	a spotlight and a mesh with the names used here exist):

//

//	global proc intersectExample()

//	{

//		intersectCmd spotLight1 pPlane1;

//		select -r spotLight1;

//	}

//

//	scriptJob -ac "spotLight1.tx" intersectExample;

//	scriptJob -ac "spotLight1.ty" intersectExample;

//	scriptJob -ac "spotLight1.tz" intersectExample;

//

//	scriptJob -ac "spotLight1.rx" intersectExample;

//	scriptJob -ac "spotLight1.ry" intersectExample;

//	scriptJob -ac "spotLight1.rz" intersectExample;

//

//////////////////////////////////////////////////////////////////////////////////////////////////



// MAIN CLASS FOR THE INTERSECTCMD COMMAND:

class intersectCmd : public MPxCommand

{

	public:

		intersectCmd();

		virtual ~intersectCmd();

		static void* creator();

		bool isUndoable() const;

		

		MStatus doIt(const MArgList&);

		MStatus undoIt();

};

#endif



// CONSTRUCTOR:

intersectCmd::intersectCmd()

{

}



// DESTRUCTOR:

intersectCmd::~intersectCmd()

{

}



// FOR CREATING AN INSTANCE OF THIS COMMAND:

void* intersectCmd::creator()

{

   return new intersectCmd;

}



// MAKE THIS COMMAND NOT UNDOABLE:

bool intersectCmd::isUndoable() const

{

   return false;

}





MStatus intersectCmd::doIt(const MArgList& args)



// Description:

// 		Determine if the ray from the spotlight intersects the mesh.

//		If it does, display the intersection points.



{

	MStatus stat = MStatus::kSuccess;



	if (args.length() != 2) 

	{

		MGlobal::displayError("Need 2 items!");

		return MStatus::kFailure;

	}



	MSelectionList activeList;

	int i;

	

	for ( i = 0; i < 2; i++)

	{

		MString strCurrSelection;

		stat = args.get(i, strCurrSelection);

		if (MStatus::kSuccess == stat) activeList.add(strCurrSelection);

	}



	MItSelectionList iter(activeList);

	MFnSpotLight fnLight;  

	MFnMesh fnMesh;

	MFnDagNode dagNod;

	MFnDependencyNode fnDN;



	float fX = 0;

	float fY = 0;

	float fZ = 0;



	for ( ; !iter.isDone(); iter.next() )

	{

		MObject tempObjectParent, tempObjectChild;

		iter.getDependNode(tempObjectParent);



		if (tempObjectParent.apiType() == MFn::kTransform)

		{

			dagNod.setObject(tempObjectParent);

			tempObjectChild = dagNod.child(0, &stat);

		}



		// check what type of object is selected

		if (tempObjectChild.apiType() == MFn::kSpotLight)

		{

			MDagPath pathToLight;

			MERR_CHK(MDagPath::getAPathTo(tempObjectParent, pathToLight), "Couldn't get a path to the spotlight");

			MERR_CHK(fnLight.setObject(pathToLight), "Failure on assigning light");

			

			stat = fnDN.setObject(tempObjectParent);



			MPlug pTempPlug = fnDN.findPlug("translateX", &stat);

			if (MStatus::kSuccess == stat)

			{

				pTempPlug.getValue(fX);

			}



			pTempPlug = fnDN.findPlug("translateY", &stat);

			if (MStatus::kSuccess == stat)

			{

				pTempPlug.getValue(fY);

			}



			pTempPlug = fnDN.findPlug("translateZ", &stat);

			if (MStatus::kSuccess == stat)

			{

				pTempPlug.getValue(fZ);

			}	

		}

		else if (tempObjectChild.apiType() == MFn::kMesh)

		{

			MDagPath pathToMesh;

			MERR_CHK(MDagPath::getAPathTo(tempObjectChild, pathToMesh), "Couldn't get a path to the spotlight");

			MERR_CHK(fnMesh.setObject(pathToMesh), "Failure on assigning light");	

		}

		else

		{

			MGlobal::displayError("Need a spotlight and a mesh");

			return MStatus::kFailure;

		}

	}



	MFloatPoint fpSource(fX, fY, fZ);

	MFloatVector fvRayDir = fnLight.lightDirection(0, MSpace::kWorld, &stat);

	MFloatPoint hitPoint;

	

	MMeshIsectAccelParams mmAccelParams = fnMesh.autoUniformGridParams();

	

	float fHitRayParam, fHitBary1, fHitBary2;

	int nHitFace, nHitTriangle;



	// a large positive number is used here for the maxParam parameter

	bool bAnyIntersection = fnMesh.anyIntersection(fpSource, fvRayDir, NULL, NULL, false,				MSpace::kWorld, (float)9999, false, &mmAccelParams, hitPoint, &fHitRayParam, &nHitFace, &nHitTriangle, 		&fHitBary1, &fHitBary2, (float)1e-6, &stat);

	

	if (! bAnyIntersection) 

	{

		MGlobal::displayInfo("There were no intersection points detected");

		return stat;

	}



	MFloatPointArray hitPoints;

	MFloatArray faHitRayParams;

	MIntArray iaHitFaces;

	MIntArray iaHitTriangles;

	MFloatArray faHitBary1;

	MFloatArray faHitBary2;



	bool bAllIntersections = fnMesh.allIntersections(fpSource, fvRayDir, NULL, NULL, false, MSpace::kWorld, 9999, false, NULL, false, hitPoints, &faHitRayParams, &iaHitFaces, &iaHitTriangles, &faHitBary1, &faHitBary2, 0.000001f, &stat);

	

	if (! bAllIntersections)

	{

		MGlobal::displayInfo("Error getting all intersections");

		return stat;

	}

	

	// check how many intersections are found

	unsigned int nNumberHitPoints = hitPoints.length();



	if (! nNumberHitPoints)

	{

		MGlobal::displayInfo("No hit points detected");

		return MStatus::kSuccess;

	}



	// Intersection exists; display intersections as spheres

	MString strCommandString = "string $strBall[] = `polySphere -r 0.5`;";

	strCommandString += "$strBallName = $strBall[0];";



	float x = 0;

	float y = 0;

	float z = 0;

	float w = 0;



	for (i = 0; i < (int)nNumberHitPoints; i++)

	{

		// get the points

		x = hitPoints[i][0];

		y = hitPoints[i][1];

		z = hitPoints[i][2];

		w = hitPoints[i][3];



		// execute some MEL to create a small sphere

		strCommandString += "setAttr ($strBallName + \".tx\") ";

		strCommandString += x;

		strCommandString += ";";



		strCommandString += "setAttr ($strBallName + \".ty\") ";

		strCommandString += y;

		strCommandString += ";";



		strCommandString += "setAttr ($strBallName + \".tz\") ";

		strCommandString += z;

		strCommandString += ";";



		MGlobal::executeCommand(strCommandString);

	}



	return stat;

}



// UNDO THE COMMAND

MStatus intersectCmd::undoIt()

{

	MStatus status;

	// undo not implemented

	return status;

}



// INITIALIZE THE PLUGIN:

MStatus initializePlugin(MObject obj)

{

	MStatus status;

	MFnPlugin plugin(obj, "Alias Systems", "6.5", "Any");



	status = plugin.registerCommand("intersectCmd", intersectCmd::creator);



	return status;

}



// UNINITIALIZE THE PLUGIN:

MStatus uninitializePlugin(MObject obj)

{

	MStatus status;

	MFnPlugin plugin(obj);



	plugin.deregisterCommand("intersectCmd");



	return status;

}