Using MurmurHash in MeshTools::Clean.

SubdivideCleanBenchmark times are untouched with this change, but the
hash should be better for MeshTools::CombineIndices, where the previous
hash generated all zeros in most cases.

src/MeshTools/Clean.h

@@ -22,6 +22,7 @@
 #include <unordered_map>
 #include <limits>
 
+#include "Utility/MurmurHash2.h"
 #include "TypeTraits.h"
 
 namespace Magnum { namespace MeshTools {
@@ -113,10 +114,7 @@ template<class Vertex, size_t vertexSize = Vertex::Size> class Clean {
         class IndexHash {
             public:
                 inline size_t operator()(const Math::Vector<size_t, vertexSize>& data) const {
-                    size_t a = 0;
-                    for(size_t i = 0; i != vertexSize; ++i)
-                        a ^= data[i];
-                    return a;
+                    return *reinterpret_cast<const size_t*>(Corrade::Utility::MurmurHash2()(reinterpret_cast<const char*>(&data), sizeof(data)).byteArray());
                 }
         };
 

src/MeshTools/Test/CMakeLists.txt

@@ -1,6 +1,6 @@
-corrade_add_test(CleanTest CleanTest.h CleanTest.cpp)
+corrade_add_test(CleanTest CleanTest.h CleanTest.cpp ${CORRADE_UTILITY_LIBRARY})
 corrade_add_test(CompressIndicesTest CompressIndicesTest.h CompressIndicesTest.cpp ${CORRADE_UTILITY_LIBRARY} ${MAGNUM_LIBRARY})
 corrade_add_test(InterleaveTest InterleaveTest.h InterleaveTest.cpp ${CORRADE_UTILITY_LIBRARY})
-corrade_add_test(SubdivideTest SubdivideTest.h SubdivideTest.cpp)
-corrade_add_test(SubdivideCleanBenchmark SubdivideCleanBenchmark.h SubdivideCleanBenchmark.cpp ${MAGNUM_PRIMITIVES_LIBRARY})
+corrade_add_test(SubdivideTest SubdivideTest.h SubdivideTest.cpp ${CORRADE_UTILITY_LIBRARY})
+corrade_add_test(SubdivideCleanBenchmark SubdivideCleanBenchmark.h SubdivideCleanBenchmark.cpp ${CORRADE_UTILITY_LIBRARY} ${MAGNUM_PRIMITIVES_LIBRARY})
 corrade_add_test(TipsifyTest TipsifyTest.h TipsifyTest.cpp ${MAGNUM_MESHTOOLS_LIBRARY})