assimp.assimp/test/unit/utSplitLargeMeshes.cpp

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#include "UnitTestPCH.h"

#include "PostProcessing/SplitLargeMeshes.h"
#include <assimp/scene.h>

using namespace std;
using namespace Assimp;

class SplitLargeMeshesTest : public ::testing::Test {
public:
    virtual void SetUp();
    virtual void TearDown();

protected:
    SplitLargeMeshesProcess_Triangle *piProcessTriangle;
    SplitLargeMeshesProcess_Vertex *piProcessVertex;
};

// ------------------------------------------------------------------------------------------------
void SplitLargeMeshesTest::SetUp() {
    // construct the processes
    this->piProcessTriangle = new SplitLargeMeshesProcess_Triangle();
    this->piProcessVertex = new SplitLargeMeshesProcess_Vertex();

    this->piProcessTriangle->SetLimit(1000);
    this->piProcessVertex->SetLimit(1000);
}

// ------------------------------------------------------------------------------------------------
void SplitLargeMeshesTest::TearDown() {
    delete this->piProcessTriangle;
    delete this->piProcessVertex;
}

// ------------------------------------------------------------------------------------------------
TEST_F(SplitLargeMeshesTest, testVertexSplit) {
    std::vector<std::pair<aiMesh *, unsigned int>> avOut;

    aiMesh *pcMesh1 = new aiMesh();
    pcMesh1->mNumVertices = 2100; // quersumme: 3
    pcMesh1->mVertices = new aiVector3D[pcMesh1->mNumVertices];
    pcMesh1->mNormals = new aiVector3D[pcMesh1->mNumVertices];

    pcMesh1->mNumFaces = pcMesh1->mNumVertices / 3;
    pcMesh1->mFaces = new aiFace[pcMesh1->mNumFaces];

    unsigned int qq = 0;
    for (unsigned int i = 0; i < pcMesh1->mNumFaces; ++i) {
        aiFace &face = pcMesh1->mFaces[i];
        face.mNumIndices = 3;
        face.mIndices = new unsigned int[3];
        face.mIndices[0] = qq++;
        face.mIndices[1] = qq++;
        face.mIndices[2] = qq++;
    }

    int iOldFaceNum = (int)pcMesh1->mNumFaces;
    piProcessVertex->SplitMesh(0, pcMesh1, avOut);

    for (std::vector<std::pair<aiMesh *, unsigned int>>::const_iterator
                    iter = avOut.begin(),
                    end = avOut.end();
            iter != end; ++iter) {
        aiMesh *mesh = (*iter).first;
        EXPECT_LT(mesh->mNumVertices, 1000U);
        EXPECT_TRUE(nullptr != mesh->mNormals);
        EXPECT_TRUE(nullptr != mesh->mVertices);

        iOldFaceNum -= mesh->mNumFaces;
        delete mesh;
    }
    EXPECT_EQ(0, iOldFaceNum);
}

// ------------------------------------------------------------------------------------------------
TEST_F(SplitLargeMeshesTest, testTriangleSplit) {
    std::vector<std::pair<aiMesh *, unsigned int>> avOut;

    // generate many, many faces with randomized indices for
    // the second mesh
    aiMesh *pcMesh2 = new aiMesh();
    pcMesh2->mNumVertices = 3000;
    pcMesh2->mVertices = new aiVector3D[pcMesh2->mNumVertices];
    pcMesh2->mNormals = new aiVector3D[pcMesh2->mNumVertices];

    pcMesh2->mNumFaces = 10000;
    pcMesh2->mFaces = new aiFace[pcMesh2->mNumFaces];

    for (unsigned int i = 0; i < pcMesh2->mNumFaces; ++i) {
        aiFace &face = pcMesh2->mFaces[i];
        face.mNumIndices = 3;
        face.mIndices = new unsigned int[3];
        face.mIndices[0] = (unsigned int)((rand() / (float)RAND_MAX) * pcMesh2->mNumVertices);
        face.mIndices[1] = (unsigned int)((rand() / (float)RAND_MAX) * pcMesh2->mNumVertices);
        face.mIndices[2] = (unsigned int)((rand() / (float)RAND_MAX) * pcMesh2->mNumVertices);
    }

    // the number of faces shouldn't change
    int iOldFaceNum = (int)pcMesh2->mNumFaces;
    piProcessTriangle->SplitMesh(0, pcMesh2, avOut);

    for (std::vector<std::pair<aiMesh *, unsigned int>>::const_iterator
                    iter = avOut.begin(),
                    end = avOut.end();
            iter != end; ++iter) {
        aiMesh *mesh = (*iter).first;
        EXPECT_LT(mesh->mNumFaces, 1000U);
        EXPECT_TRUE(nullptr != mesh->mNormals);
        EXPECT_TRUE(nullptr != mesh->mVertices);

        iOldFaceNum -= mesh->mNumFaces;
        delete mesh;
    }
    EXPECT_EQ(0, iOldFaceNum);
}