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我不知道为什么，但我的 VBO 在一帧后消失（初始帧在原点显示它的角度不正确） 下面是我的矩阵类、绘制方法和顶点着色器的代码。

Matrix::Matrix() { 
    for (int i = 0; i < 16; i++) {
        values[i] = 0;
    }
}

Matrix Matrix::operator*(const Matrix &matrix) {
    Matrix result;

    for (int i = 0; i < 4; i++) {
        for (int j = 0; j < 4; j++) {
            for (int k = 0; k < 4; k++) {
                result.values[i * 4 + j] += this->values[i * 4 + k] * matrix.values[k * 4 + j];
            }
        }
    }

    return result;
}

Matrix Matrix::Perspective(float fov, float aspect, float znear, float zfar) {
    Matrix matrix;

    float xymax = znear * tan(fov * 0.00872664);
    float q = -(zfar * znear) / (zfar - znear);
    float val = znear / xymax;

    matrix.values[0] = val / aspect;
    matrix.values[5] = val;
    matrix.values[10] = q;
    matrix.values[11] = -1;
    matrix.values[14] = 2 * q;

    return matrix;
}

Matrix Matrix::LookAt(Vector3f eye, Vector3f target, Vector3f up) {

    Vector3f zaxis = Vector3f::Normalize(target - eye);
    Vector3f xaxis = Vector3f::Normalize(Vector3f::CrossProduct(up, zaxis));
    Vector3f yaxis = Vector3f::CrossProduct(zaxis, xaxis);
    // vy doesn't need to be normalized because it's a cross product of 2 normalized vectors

    Matrix viewMatrix;
    viewMatrix.values[0]  = xaxis.x;
    viewMatrix.values[1]  = xaxis.y;
    viewMatrix.values[2]  = xaxis.z;
    viewMatrix.values[3]  = 0;

    viewMatrix.values[4]  = yaxis.x;
    viewMatrix.values[5]  = yaxis.y;
    viewMatrix.values[6]  = yaxis.z;
    viewMatrix.values[7]  = 0;

    viewMatrix.values[8]  = zaxis.x;
    viewMatrix.values[9]  = zaxis.y;
    viewMatrix.values[10] = zaxis.z;
    viewMatrix.values[11] = 0;

    viewMatrix.values[12] = 0;
    viewMatrix.values[13] = 0;
    viewMatrix.values[14] = 0;
    viewMatrix.values[15] = 1;

    Matrix translationMatrix = Matrix::Identity();
    translationMatrix.values[12] = -eye.x;
    translationMatrix.values[13] = -eye.y;
    translationMatrix.values[14] = -eye.z;

    return translationMatrix * viewMatrix;
}

Matrix Matrix::Identity() {
    Matrix matrix;
    matrix.values[0] = 1;
    matrix.values[5] = 1;
    matrix.values[10] = 1;
    matrix.values[15] = 1;
    return matrix;
}

变量：

static const GLfloat g_vertex_buffer_data[] = 
{
    -1.0f, -1.0f, 0.0f,
    1.0f, -1.0f, 0.0f,
    0.0f, 1.0f, 0.0f
};
GLuint vertexbuffer;
GLuint programID;

绘制方法：

void draw() {
    glClearColor(0.5, 0.5, 0.5, 1.0);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);
    glUseProgram(programID);

    Matrix projection = Matrix::Perspective(45.0f, (float)(screen_size.x) / screen_size.y, 0.1f, 1000.0f);
    Matrix view = Matrix::LookAt(Vector3f(4, 3, 3), Vector3f(0, 0, 0), Vector3f(0, 1, 0));
    Matrix model = Matrix::Identity();
    Matrix mvp = projection * view * model;

    GLuint matrixID = glGetUniformLocation(programID, "mvp");
    glUniformMatrix4fv(matrixID, 1, GL_FALSE, mvp.values);

    int positionId = glGetAttribLocation(programID, "position");
    glEnableVertexAttribArray(positionId);
    glBindBuffer(GL_ARRAY_BUFFER, vertexbuffer);
    glVertexAttribPointer(positionId, 3, GL_FLOAT, GL_FALSE, 0, (void *)0);

    glDrawArrays(GL_TRIANGLES, 0, 3);
    glDisableVertexAttribArray(positionId);

    glutSwapBuffers();
}

顶点着色器：

in vec3 position;
uniform mat4 mvp;

void main() {
    gl_Position = mvp * vec4(position, 1);
}
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