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創建對象時“列表迭代器不可取消”

[英]“list iterator not dereferencable” on creation of object

我正在Visual Studio中使用C ++和QT創建計算機圖形項目。

我收到此錯誤的行是

quad *bodyQuad = &quad(bodyTri1, bodyTri2);

在以下方法中:

void MyGLWidget::createCharacter1(tree *t, node *root) {
    triangle bodyTri1 = triangle(vec3(4, 0, 0), vec3(-1, 1, 0));
    triangle bodyTri2 = triangle(vec3(-6, 0, 0), vec3(-1, -1, 0));
    bodyTri2 = *bodyTri2.applyTransform(mat3::translation2D(5, 1));
    quad *bodyQuad = &quad(bodyTri1, bodyTri2);
    root = new node(bodyQuad, 2);
}

trianglequad都從虛擬shape類派生。 shape類中有一個std::list ,用於存儲頂點。

node還有一個std::list用於存儲其子node

trianglequad的構造函數中,將頂點添加到列表中

三角形的構造函數

triangle::triangle(const vec3& vector1, const vec3& vector2) {
    numTriangles = 1;
    isOneColor = true;
    vec3 origin = vec3(0, 0, 1);// '1' to signify a point
    data = mat3(vector1, vector2, origin);
    data = data.transpose();

    //push "origin" vertex
    vertices.push_back(data[2]);
    //make sure point/vector convention followed, and push "base" vertex
    vertices.push_back(data[0] + vec3(0, 0, 1));
    //make sure point/vector convention followed, and push "height" vertex
    vertices.push_back(data[1] + vec3(0, 0, 1));

}

Quad的構造函數

quad::quad(triangle triangle1, triangle triangle2) {

    numTriangles = 2;
    isOneColor = true;

    data[0] = triangle1;
    data[1] = triangle2;

    std::list<vec3> tri1Vertices = data[0].getVertices();
    std::list<vec3> tri2Vertices = data[1].getVertices();

    for (size_t i = 0; i < tri1Vertices.size(); i++) {
        vertices.push_back(tri1Vertices.front());
        tri1Vertices.pop_front();
    }

    for (size_t i = 0; i < tri2Vertices.size(); i++) {
        vertices.push_back(tri2Vertices.front());
        tri2Vertices.pop_front();
    }
}

我的問題是我的applyTransform()返回一個shape指針,但是在我的return語句中,我只是取消引用&一個applyTransform()中使用的臨時變量,而不是使用new關鍵字。

謝謝所有幫助的人。

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