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glBufferData上的段错误

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我'm trying to port my fixed function pipeline openGL code to use GLSL, but I'与 glBufferData 发生了段错误 . 这对固定功能的东西都很好(即我可以渲染加载的网格没有问题) .

这是加载顶点的代码(来自AssImp导入器库):

在Mesh.h文件中定义:

...
glm::detail::uint32 vaoId_[];
    glm::detail::uint32 vboIds_[];

    std::vector< glm::vec3 > vertices_;
    std::vector< glm::vec3 > normals_;
    std::vector< glm::vec2 > textureCoordinates_;
    std::vector< glm::vec4 > colors_;
...

在Mesh.cpp中实现:

...
Mesh::Mesh(const aiMesh* mesh) {
    vaoId_[1];
    vboIds_[4];

    BOOST_LOG_TRIVIAL(debug) << "loading mesh...";

    glm::detail::uint32 currentIndex = 0;

    for (glm::detail::uint32 t = 0; t < mesh->mNumFaces; ++t) {
        const aiFace* face = &mesh->mFaces[t];
        GLenum face_mode;

        switch(face->mNumIndices) {
            case 1: face_mode = GL_POINTS; break;
            case 2: face_mode = GL_LINES; break;
            case 3: face_mode = GL_TRIANGLES; break;
            default: face_mode = GL_POLYGON; break;
        }

        glm::detail::uint32 numIndices = face->mNumIndices;

        vertices_.resize( currentIndex + numIndices );
        normals_.resize( currentIndex + numIndices );
        textureCoordinates_.resize( currentIndex + numIndices );
        colors_.resize( currentIndex + numIndices );

        //BOOST_LOG_TRIVIAL(debug) << "loading face: " << face->mNumIndices;
        // go through all vertices in face
        for(glm::detail::uint32 i = 0; i < numIndices; i++) {
            // get group index for current index i
            int vertexIndex = face->mIndices[i];

            if (mesh->mNormals != 0) {
                vertices_[currentIndex + i]     = glm::vec3( mesh->mVertices[vertexIndex].x, mesh->mVertices[vertexIndex].y, mesh->mVertices[vertexIndex].z );
                normals_[currentIndex + i]      = glm::vec3( mesh->mNormals[vertexIndex].x, mesh->mNormals[vertexIndex].y, mesh->mNormals[vertexIndex].z );
            }

            if (mesh->HasTextureCoords(0)) {
                textureCoordinates_[currentIndex + i] = glm::vec2( mesh->mTextureCoords[0][vertexIndex].x, mesh->mTextureCoords[0][vertexIndex].y );
            }

            //utilities::AssImpUtilities::color4_to_vec4(&mesh->mColors[0][vertexIndex], colors_[colors_.size() + i]);
            if (mesh->mColors[0] != 0) {
                colors_[currentIndex + i]           = glm::vec4(
                                                        (float)mesh->mColors[0][vertexIndex].a,
                                                        (float)mesh->mColors[0][vertexIndex].b,
                                                        (float)mesh->mColors[0][vertexIndex].g,
                                                        (float)mesh->mColors[0][vertexIndex].r
                                                    );
            }           
        }

        currentIndex += 3;
    }

    BOOST_LOG_TRIVIAL(debug) << "loading mesh into video memory...";

    BOOST_LOG_TRIVIAL(debug) << "blah: " << vertices_.size();
    BOOST_LOG_TRIVIAL(debug) << "blah: " << ( sizeof(glm::vec3) );
    BOOST_LOG_TRIVIAL(debug) << "blah: " << ( &vertices_[0] );

    // create our vao
    glGenVertexArrays(1, &vaoId_[0]);
    glBindVertexArray(vaoId_[0]);

    // create our vbos
    //glGenBuffers(4, &vboIds_[0]);
    glGenBuffers(1, &vboIds_[0]); // Using only '1' for now (otherwise causes seg fault)
    glBindBuffer(GL_ARRAY_BUFFER, vboIds_[0]);
    glBufferData(GL_ARRAY_BUFFER, vertices_.size() * sizeof(glm::vec3), &vertices_[0], GL_STATIC_DRAW);

    glEnableVertexAttribArray(0);
    glVertexAttribPointer(0, 3, GL_FLOAT, GL_FALSE, 0, 0);

    // Disable our Vertex Buffer Object
    glBindVertexArray(0);

    BOOST_LOG_TRIVIAL(debug) << "done loading mesh...";
}
...

当我打电话给 glBufferData(GL_ARRAY_BUFFER, vertices_.size() * sizeof(glm::vec3), &vertices_[0], GL_STATIC_DRAW); 时,我似乎无法弄清楚为什么opengl会给出一个段错误 .

完整的错误是(在linux中使用gdb):

程序接收信号SIGSEGV,分段故障 . 0x00007fffefb1ae70在? ()来自/usr/lib/x86_64-linux-gnu/libnvidia-glcore.so.304.64

有人有主意吗?

2 回答

  • 2

    在构造函数的顶部是什么?

    vaoId_[1];
    vboIds_[4];
    

    看起来你的类包含大小为零的数组(除了作为最后一个数据成员之外,甚至不应该允许它,我不知道编译器如何允许你有两个这样的数组)并且你正在写超出这些数据的边界数组,覆盖下一个成员( vertices_ 向量的元数据) . 这会破坏 vertices_ 的大小或数据指针部分,然后将已删除的数据传递给 glBufferData ,并带来可预测的不良后果 .

    线索是 glGenBuffers(4, &vboIds_[0]); 也破坏了你的程序 . 它's because you don'有任何名为 vboIds 的空间用于OpenGL来存储结果 .

    更改

    glm::detail::uint32 vaoId_[];
    glm::detail::uint32 vboIds_[];
    

    实际上有正确的尺寸 . 没有维度的数组需要额外的关注,只能在对象的末尾完成,并防止子类化 . 尽可能避免 . 如果大小可变,请指定尺寸或使用矢量 .

  • 4

    您需要在 glBufferData 之前调用 glBindBuffer .

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