c++ - 如何访问结构中定义的变量

Question

struct POINT3DID 
{
    unsigned int newID;
    float x, y, z;
};

typedef std::map<unsigned int, POINT3DID> ID2POINT3DID;

ID2POINT3DID m_i2pt3idVertices;

谁能告诉我如何使用 m_i2pt3idVertices 访问变量 x、y 和 z

Answer 1

m_i2pt3idVertices 是用于存储POINT3DID 对象的容器。它单独没有成员变量 x、y 或 z。不过，您可以将 POINT3DID 放入其中:

m_i2pt3idVertices[0] = POINT3DID(); // Put a POINT3DID into key 0

m_i2pt3idVertices[0].x = 1.0f; // Assign x for key 0
m_i2pt3idVertices[0].y = 2.0f; // Assign y for key 0
m_i2pt3idVertices[0].z = 3.0f; // Assign z for key 0