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//
//		            Box Box Intersection
//
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#include "CKAll.h"

CKObjectDeclaration	*FillBehaviorFrustumObjectIntersectionDecl();
CKERROR CreateFrustumObjectIntersectionProto(CKBehaviorPrototype **);
int FrustumObjectIntersection(const CKBehaviorContext& behcontext);


CKObjectDeclaration	*FillBehaviorFrustumObjectIntersectionDecl()
{
	CKObjectDeclaration *od = CreateCKObjectDeclaration("Frustum Object Intersection");	
	od->SetDescription("Detects the collision between a camera frustum and an object.");
	/* rem:
	<SPAN CLASS=in>In: </SPAN>triggers the process.<BR>
	<BR>
	<SPAN CLASS=out>True: </SPAN>is activated if the camera frustum and the object are in intersection.<BR>
	<SPAN CLASS=out>False: </SPAN>is activated if the camera frustum and the object are not in intersection.<BR>
	<BR>
	<SPAN CLASS=pin>Entity 0: </SPAN>first entity to be tested.<BR>
	<SPAN CLASS=pin>Entity 1: </SPAN>second entity to be tested.<BR>
	<SPAN CLASS=pin>Hierarchy 0: </SPAN>specify whether to concider the bounding sphere of the first entity and its children, or just the bounding sphere of the first entity.<BR>
	<SPAN CLASS=pin>Hierarchy 1: </SPAN>specify whether to concider the bounding sphere of the second entity and its children, or just the bounding sphere of the second entity.<BR>
	<BR>
	This building block detects the collision between two entity's bounding spheres.<BR>
	*/
	od->SetCategory("Collisions/Intersection");
	od->SetType( CKDLL_BEHAVIORPROTOTYPE);
	od->SetGuid(CKGUID(0x4d6075e1,0x2dda272e));
	od->SetAuthorGuid(VIRTOOLS_GUID);
	od->SetAuthorName("Virtools");
	od->SetVersion(0x00010000);
	od->SetCreationFunction(CreateFrustumObjectIntersectionProto);
	od->SetCompatibleClassId(CKCID_CAMERA);
	return od;
}


CKERROR CreateFrustumObjectIntersectionProto(CKBehaviorPrototype **pproto)
{
	CKBehaviorPrototype *proto = CreateCKBehaviorPrototype("Frustum Object Intersection");
	if(!proto) return CKERR_OUTOFMEMORY;

	proto->DeclareInput("In");

	proto->DeclareOutput("True");
	proto->DeclareOutput("False");
	
	proto->DeclareInParameter("Object",CKPGUID_3DENTITY);
	proto->DeclareInParameter("Local",CKPGUID_BOOL,"FALSE");
	proto->DeclareInParameter("Hierarchy",CKPGUID_BOOL,"FALSE");

	proto->SetFlags(CK_BEHAVIORPROTOTYPE_NORMAL);
	proto->SetFunction(FrustumObjectIntersection);
	proto->SetBehaviorFlags(CKBEHAVIOR_TARGETABLE);

	*pproto = proto;
	return CK_OK;
}



int FrustumObjectIntersection(const CKBehaviorContext& behcontext)
{
	CKBehavior* beh = behcontext.Behavior;
	// Set Input state
	beh->ActivateInput(0,FALSE);
	
	CKCamera* cam = (CKCamera*)beh->GetTarget();
	if (!cam) {
		beh->ActivateOutput(1);
		return CKBR_OK;
	}

	CK3dEntity* ent = (CK3dEntity*)beh->GetInputParameterObject(0);
	if (!ent) {
		beh->ActivateOutput(1);
		return CKBR_OK;
	}
	
	BOOL local = FALSE;
	beh->GetInputParameterValue(1,&local);

	BOOL hiera = FALSE;
	beh->GetInputParameterValue(2,&hiera);

	int width,height;
	VxVector pos,dir,up,right;
	cam->GetPosition(&pos);
	cam->GetOrientation(&dir,&up,&right);
	cam->GetAspectRatio(width,height);
	VxFrustum frustum(pos,right,up,dir,cam->GetFrontPlane(),cam->GetBackPlane(),cam->GetFov(),(float)height/width);
	
	VxBbox box;
	if (local) {
		if (!hiera) {
			box = ent->GetBoundingBox(TRUE);
		} else {
			box = ent->GetHierarchicalBox(TRUE);
		}

		if (VxIntersect::FrustumOBB(frustum,box,ent->GetWorldMatrix())) {
			beh->ActivateOutput(0);
		} else {
			beh->ActivateOutput(1);
		}
	} else {
		if (!hiera) {
			box = ent->GetBoundingBox(FALSE);
		} else {
			box = ent->GetHierarchicalBox(FALSE);
		}

		if (VxIntersect::FrustumAABB(frustum,box)) {
			beh->ActivateOutput(0);
		} else {
			beh->ActivateOutput(1);
		}
	}

	return CKBR_OK;
}