assimp/test/unit/Common/utSpatialSort.cpp

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#include "UnitTestPCH.h"

#include <assimp/SpatialSort.h>

using namespace Assimp;

class utSpatialSort : public ::testing::Test {
public
        :
    aiVector3D *vecs;

protected:
    void SetUp() override {
        ::srand(static_cast<unsigned>(time(nullptr)));
        vecs = new aiVector3D[100];
        for (size_t i = 0; i < 100; ++i) {
            vecs[i].x = static_cast<float>(rand()) / (static_cast<float>(RAND_MAX / 100));
            vecs[i].y = static_cast<float>(rand()) / (static_cast<float>(RAND_MAX / 100));
            vecs[i].z = static_cast<float>(rand()) / (static_cast<float>(RAND_MAX / 100));
        }
    }

    void TearDown() override {
        delete[] vecs;
    }
};

TEST_F( utSpatialSort, findIdenticalsTest ) {
    SpatialSort sSort;
    sSort.Fill(vecs, 100, sizeof(aiVector3D));

    std::vector<unsigned int> indices;
    sSort.FindIdenticalPositions(vecs[0], indices);
    EXPECT_EQ(1u, indices.size());
}

TEST_F(utSpatialSort, findPositionsTest) {
    SpatialSort sSort;
    sSort.Fill(vecs, 100, sizeof(aiVector3D));

    std::vector<unsigned int> indices;
    sSort.FindPositions(vecs[0], 0.01f, indices);
    EXPECT_EQ(1u, indices.size());
}

TEST_F(utSpatialSort, highlyDisplacedPositionsTest) {
    // Make a cube of positions, and then query it using the SpatialSort object.
    constexpr unsigned int verticesPerAxis = 10;
    constexpr ai_real step = 0.001f;
    // Note the large constant offset here.
    constexpr ai_real offset = 5000.0f - (0.5f * verticesPerAxis * step);
    constexpr unsigned int totalNumPositions = verticesPerAxis * verticesPerAxis * verticesPerAxis;
    aiVector3D* positions = new aiVector3D[totalNumPositions];
    for (unsigned int x = 0; x < verticesPerAxis; ++x) {
        for (unsigned int y = 0; y < verticesPerAxis; ++y) {
            for (unsigned int z = 0; z < verticesPerAxis; ++z) {
                const unsigned int index = (x * verticesPerAxis * verticesPerAxis) + (y * verticesPerAxis) + z;
                positions[index] = aiVector3D(offset + (x * step), offset + (y * step), offset + (z * step));
            }
        }
    }

    SpatialSort sSort;
    sSort.Fill(positions, totalNumPositions, sizeof(aiVector3D));

    // Enough to find a point and its 6 immediate neighbors, but not any other point.
    const ai_real epsilon = 1.1f * step;
    std::vector<unsigned int> indices;
    // Iterate through the _interior_ points of the cube.
    for (unsigned int x = 1; x < verticesPerAxis - 1; ++x) {
        for (unsigned int y = 1; y < verticesPerAxis - 1; ++y) {
            for (unsigned int z = 1; z < verticesPerAxis - 1; ++z) {
                const unsigned int index = (x * verticesPerAxis * verticesPerAxis) + (y * verticesPerAxis) + z;
                sSort.FindPositions(positions[index], epsilon, indices);
                ASSERT_EQ(7u, indices.size());
            }
        }
    }
    delete[] positions;
}