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#include <NvBlastGlobals.h>
#include "NvBlastExtAuthoringCollisionBuilderImpl.h"
#include <NvBlastExtApexSharedParts.h>
#include <NvBlastExtAuthoringInternalCommon.h>

#include <NvBlastExtAuthoringBooleanTool.h>
#include <NvBlastExtAuthoringMeshImpl.h>
#include <NvBlastExtAuthoringMeshUtils.h>
#include <NvBlastPxSharedHelpers.h>
#include <VHACD.h>
#include <vector>

using namespace physx;

namespace Nv
{
namespace Blast
{

#define SAFE_ARRAY_NEW(T, x) ((x) > 0) ? reinterpret_cast<T*>(NVBLAST_ALLOC(sizeof(T) * (x))) : nullptr;
#define SAFE_ARRAY_DELETE(x) if (x != nullptr) {NVBLAST_FREE(x); x = nullptr;}

void trimCollisionGeometry(ConvexMeshBuilder& cmb, uint32_t chunksCount, CollisionHull** in, const uint32_t* chunkDepth)
{
	std::vector<std::vector<PxPlane> > chunkMidplanes(chunksCount);
	std::vector<PxVec3> centers(chunksCount);
	std::vector<PxBounds3> hullsBounds(chunksCount);
	for (uint32_t i = 0; i < chunksCount; ++i)
	{
		hullsBounds[i].setEmpty();
		centers[i] = PxVec3(0, 0, 0);
		for (uint32_t p = 0; p < in[i]->pointsCount; ++p)
		{
			centers[i] += toPxShared(in[i]->points[p]);
			hullsBounds[i].include(toPxShared(in[i]->points[p]));
		}
		centers[i] = hullsBounds[i].getCenter();
	}

	Separation params;
	for (uint32_t hull = 0; hull < chunksCount; ++hull)
	{
		for (uint32_t hull2 = hull + 1; hull2 < chunksCount; ++hull2)
		{
			if (chunkDepth[hull] != chunkDepth[hull2])
			{
				continue;
			}
			if (importerHullsInProximityApexFree(in[hull]->pointsCount, toPxShared(in[hull]->points), hullsBounds[hull],
			                                     PxTransform(PxIdentity), PxVec3(1, 1, 1), in[hull2]->pointsCount,
			                                     toPxShared(in[hull2]->points), hullsBounds[hull2], PxTransform(PxIdentity),
			                                     PxVec3(1, 1, 1), 0.0, &params) == false)
			{
				continue;
			}
			PxVec3 c1 = centers[hull];
			PxVec3 c2 = centers[hull2];
			float d = FLT_MAX;
			PxVec3 n1;
			PxVec3 n2;
			for (uint32_t p = 0; p < in[hull]->pointsCount; ++p)
			{
				float ld = (toPxShared(in[hull]->points[p]) - c2).magnitude();
				if (ld < d)
				{
					n1 = toPxShared(in[hull]->points[p]);
					d = ld;
				}
			}
			d = FLT_MAX;
			for (uint32_t p = 0; p < in[hull2]->pointsCount; ++p)
			{
				float ld = (toPxShared(in[hull2]->points[p]) - c1).magnitude();
				if (ld < d)
				{
					n2 = toPxShared(in[hull2]->points[p]);
					d = ld;
				}
			}

			PxVec3 dir = c2 - c1;

			PxPlane pl = PxPlane((n1 + n2) * 0.5, dir.getNormalized());
			chunkMidplanes[hull].push_back(pl);
			PxPlane pl2 = PxPlane((n1 + n2) * 0.5, -dir.getNormalized());
			chunkMidplanes[hull2].push_back(pl2);		
		}
	}
	std::vector<PxVec3> hPoints;
	for (uint32_t i = 0; i < chunksCount; ++i)
	{
		std::vector<Facet> facets;
		std::vector<Vertex> vertices;
		std::vector<Edge> edges;
		for (uint32_t fc = 0; fc < in[i]->polygonDataCount; ++fc)
		{
			Facet nFc;
			nFc.firstEdgeNumber = edges.size();
			auto& pd = in[i]->polygonData[fc];
			uint32_t n = pd.vertexCount;
			for (uint32_t ed = 0; ed < n; ++ed)
			{
				uint32_t vr1 = in[i]->indices[(ed) + pd.indexBase];
				uint32_t vr2 = in[i]->indices[(ed + 1) % n + pd.indexBase];
				edges.push_back({vr1, vr2});
			}
			nFc.edgesCount = n;
			facets.push_back(nFc);
		}
		vertices.resize(in[i]->pointsCount);
		for (uint32_t vr = 0; vr < in[i]->pointsCount; ++vr)
		{
			vertices[vr].p = in[i]->points[vr];
		}
		Mesh* hullMesh = new MeshImpl(vertices.data(), edges.data(), facets.data(), vertices.size(), edges.size(), facets.size());
		BooleanEvaluator evl;
		//I think the material ID is unused for collision meshes so harcoding MATERIAL_INTERIOR is ok
		Mesh* cuttingMesh = getCuttingBox(PxVec3(0, 0, 0), PxVec3(0, 0, 1), 40, 0, kMaterialInteriorId);
		for (uint32_t p = 0; p < chunkMidplanes[i].size(); ++p)
		{
			PxPlane& pl = chunkMidplanes[i][p];
			setCuttingBox(pl.pointInPlane(), pl.n.getNormalized(), cuttingMesh, 60, 0);
			evl.performFastCutting(hullMesh, cuttingMesh, BooleanConfigurations::BOOLEAN_DIFFERENCE());
			Mesh* result = evl.createNewMesh();
			if (result == nullptr)
			{
				break;
			}
			delete hullMesh;
			hullMesh = result;
		}
		delete cuttingMesh;
		if (hullMesh == nullptr)
		{
			continue;
		}
		hPoints.clear();
		hPoints.resize(hullMesh->getVerticesCount());
		for (uint32_t v = 0; v < hullMesh->getVerticesCount(); ++v)
		{
			hPoints[v] = toPxShared(hullMesh->getVertices()[v].p);
		}
		delete hullMesh;
		if (in[i] != nullptr)
		{
			delete in[i];
		}
		in[i] = cmb.buildCollisionGeometry(hPoints.size(), fromPxShared(hPoints.data()));
	}
}

int32_t buildMeshConvexDecomposition(ConvexMeshBuilder& cmb, const Triangle* mesh, uint32_t triangleCount,
                                     const ConvexDecompositionParams& iparams, CollisionHull**& convexes)
{
	std::vector<float> coords(triangleCount * 9);
	std::vector<uint32_t> indices(triangleCount * 3);

	uint32_t indx = 0;
	uint32_t indxCoord = 0;

	PxBounds3 chunkBound = PxBounds3::empty();
	for (uint32_t i = 0; i < triangleCount; ++i)
	{
		for (auto& t : { mesh[i].a.p , mesh[i].b.p , mesh[i].c.p })
		{

			chunkBound.include(toPxShared(t));
			coords[indxCoord] = t.x;
			coords[indxCoord + 1] = t.y;
			coords[indxCoord + 2] = t.z;
			indxCoord += 3;
		}
		indices[indx] = indx;
		indices[indx + 1] = indx + 1;
		indices[indx + 2] = indx + 2;
		indx += 3;
	}

	PxVec3 rsc = chunkBound.getDimensions();

	for (uint32_t i = 0; i < coords.size(); i += 3)
	{
		coords[i] = (coords[i] - chunkBound.minimum.x) / rsc.x;
		coords[i + 1] = (coords[i + 1] - chunkBound.minimum.y) / rsc.y;
		coords[i + 2] = (coords[i + 2] - chunkBound.minimum.z) / rsc.z;
	}
	
	VHACD::IVHACD* decomposer = VHACD::CreateVHACD();

	VHACD::IVHACD::Parameters vhacdParam;
	vhacdParam.m_maxConvexHulls = iparams.maximumNumberOfHulls;
	vhacdParam.m_resolution = iparams.voxelGridResolution;
	vhacdParam.m_concavity = iparams.concavity;
	vhacdParam.m_oclAcceleration = false;
	//TODO vhacdParam.m_callback
	vhacdParam.m_minVolumePerCH = 0.003f; // 1.f / (3 * vhacdParam.m_resolution ^ (1 / 3));

	decomposer->Compute(coords.data(), triangleCount * 3, indices.data(), triangleCount, vhacdParam);

	const uint32_t nConvexHulls = decomposer->GetNConvexHulls();
	convexes = SAFE_ARRAY_NEW(CollisionHull*, nConvexHulls);

	for (uint32_t i = 0; i < nConvexHulls; ++i)
	{
		VHACD::IVHACD::ConvexHull hl;
		decomposer->GetConvexHull(i, hl);
		std::vector<PxVec3> vertices;
		for (uint32_t v = 0; v < hl.m_nPoints; ++v)
		{
			vertices.push_back(PxVec3(hl.m_points[v * 3], hl.m_points[v * 3 + 1], hl.m_points[v * 3 + 2]));
			vertices.back().x = vertices.back().x * rsc.x + chunkBound.minimum.x;
			vertices.back().y = vertices.back().y * rsc.y + chunkBound.minimum.y;
			vertices.back().z = vertices.back().z * rsc.z + chunkBound.minimum.z;

		}
		convexes[i] = cmb.buildCollisionGeometry(vertices.size(), fromPxShared(vertices.data()));
	}
	//VHACD::~VHACD called from release does nothign and does not call Clean()
	decomposer->Clean();
	decomposer->Release();

	return nConvexHulls;
}



} // namespace Blast
} // namespace Nv