_In_reads_(nFaces * 3) const index_t* indices, size_t nFaces,

size_t nVerts, _Out_writes_(nVerts) uint32_t* vertexRemap,

_Out_opt_ size_t* trailingUnused) noexcept

{

if (!indices || !nFaces || !nVerts || !vertexRemap)

return E_INVALIDARG;

if (nVerts >= index_t(-1))

return E_INVALIDARG;

if (trailingUnused)

{

*trailingUnused = 0;

}

if ((uint64_t(nFaces) * 3) >= UINT32_MAX)

return HRESULT_E_ARITHMETIC_OVERFLOW;

std::unique_ptr<uint32_t[]> tempRemap(new (std::nothrow) uint32_t[nVerts]);

if (!tempRemap)

return E_OUTOFMEMORY;

memset(tempRemap.get(), 0xff, sizeof(uint32_t) * nVerts);

uint32_t curvertex = 0;

for (size_t j = 0; j < (nFaces * 3); ++j)

{

index_t curindex = indices[j];

if (curindex == index_t(-1))

continue;

if (curindex >= nVerts)

return E_UNEXPECTED;

if (tempRemap[curindex] == UNUSED32)

{

tempRemap[curindex] = curvertex;

++curvertex;

}

}

// inverse lookup

memset(vertexRemap, 0xff, sizeof(uint32_t) * nVerts);

size_t unused = 0;

for (uint32_t j = 0; j < nVerts; ++j)

{

uint32_t vertindex = tempRemap[j];

if (vertindex == UNUSED32)

{

++unused;

}

else

{

if (vertindex >= nVerts)

return E_UNEXPECTED;

vertexRemap[vertindex] = j;

}

}

if (trailingUnused)

{

*trailingUnused = unused;

}

return S_OK;

size_t nFaces,

uint32_t* attributes,

uint32_t* faceRemap)

{

if (!nFaces || !attributes || !faceRemap)

return E_INVALIDARG;

if ((uint64_t(nFaces) * 3) >= UINT32_MAX)

return HRESULT_E_ARITHMETIC_OVERFLOW;

using intpair_t = std::pair<uint32_t, uint32_t>;

std::vector<intpair_t> list;

list.reserve(nFaces);

for (uint32_t j = 0; j < nFaces; ++j)

{

list.emplace_back(intpair_t(attributes[j], j));

}

std::stable_sort(list.begin(), list.end(), [](const intpair_t& a, const intpair_t& b) noexcept -> bool

{

return (a.first < b.first);

});

auto it = list.begin();

for (uint32_t j = 0; j < nFaces; ++j, ++it)

{

attributes[j] = it->first;

faceRemap[j] = it->second;

}

return S_OK;

const uint16_t* indices,

size_t nFaces,

size_t nVerts,

uint32_t* vertexRemap,

size_t* trailingUnused) noexcept

{

return OptimizeVerticesImpl<uint16_t>(indices, nFaces, nVerts, vertexRemap, trailingUnused);

const uint32_t* indices,

size_t nFaces,

size_t nVerts,

uint32_t* vertexRemap,

size_t* trailingUnused) noexcept

{

return OptimizeVerticesImpl<uint32_t>(indices, nFaces, nVerts, vertexRemap, trailingUnused);