assimp.assimp/test/unit/utTriangulate.cpp

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#include "UnitTestPCH.h"

#include <assimp/scene.h>

#include "PostProcessing/TriangulateProcess.h"

using namespace std;
using namespace Assimp;

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

protected:
    aiMesh *pcMesh;
    TriangulateProcess *piProcess;
};

void TriangulateProcessTest::SetUp() {
    piProcess = new TriangulateProcess();
    pcMesh = new aiMesh();

    pcMesh->mNumFaces = 1000;
    pcMesh->mFaces = new aiFace[1000];
    pcMesh->mVertices = new aiVector3D[10000];

    pcMesh->mPrimitiveTypes = aiPrimitiveType_POINT | aiPrimitiveType_LINE | aiPrimitiveType_POLYGON;

    for (unsigned int m = 0, t = 0, q = 4; m < 1000; ++m) {
        ++t;
        aiFace &face = pcMesh->mFaces[m];
        face.mNumIndices = t;
        if (4 == t) {
            face.mNumIndices = q++;
            t = 0;

            if (10 == q) q = 4;
        }
        face.mIndices = new unsigned int[face.mNumIndices];
        for (unsigned int p = 0; p < face.mNumIndices; ++p) {
            face.mIndices[p] = pcMesh->mNumVertices;

            // construct fully convex input data in ccw winding, xy plane
            aiVector3D &v = pcMesh->mVertices[pcMesh->mNumVertices++];
            v.z = 0.f;
            v.x = cos(p * (float)(AI_MATH_TWO_PI) / face.mNumIndices);
            v.y = sin(p * (float)(AI_MATH_TWO_PI) / face.mNumIndices);
        }
    }
}

void TriangulateProcessTest::TearDown() {
    delete piProcess;
    delete pcMesh;
}

TEST_F(TriangulateProcessTest, testTriangulation) {
    piProcess->TriangulateMesh(pcMesh);

    for (unsigned int m = 0, t = 0, q = 4, max = 1000, idx = 0; m < max; ++m) {
        ++t;
        aiFace &face = pcMesh->mFaces[m];
        if (4 == t) {
            t = 0;
            max += q - 3;

            std::vector<bool> ait(q, false);

            for (unsigned int i = 0, tt = q - 2; i < tt; ++i, ++m) {
                aiFace &curFace = pcMesh->mFaces[m];
                EXPECT_EQ(3U, curFace.mNumIndices);

                for (unsigned int qqq = 0; qqq < curFace.mNumIndices; ++qqq) {
                    ait[curFace.mIndices[qqq] - idx] = true;
                }
            }
            for (std::vector<bool>::const_iterator it = ait.begin(); it != ait.end(); ++it) {
                EXPECT_TRUE(*it);
            }
            --m;
            idx += q;
            if (++q == 10) {
                q = 4;
            }
        } else {
            EXPECT_EQ(t, face.mNumIndices);

            for (unsigned int i = 0; i < face.mNumIndices; ++i, ++idx) {
                EXPECT_EQ(idx, face.mIndices[i]);
            }
        }
    }

    // we should have no valid normal vectors now because we aren't a pure polygon mesh
    EXPECT_TRUE(pcMesh->mNormals == nullptr);
}