Обратная связь преобразования OpenGL 4.3 или 4.5 не работает

Есть два сегмента отладки printf. Первый печатает правильные данные, а второй нет. Где я ошибся? О, я использую один и тот же вершинный и фрагментный шейдер как для получения данных вершин, так и для их повторного рисования.

#include "Dependencies\glew\glew.h"
#include "Dependencies\freeglut\freeglut.h"
#include <cstdio>

GLuint program;
GLuint VAOs[2];
GLuint VBOs[2];
GLuint TFBs[1];

char *vertSrc =
"#version 450 core\n"
"in vec4 vPosition;"
"in vec4 vColor;"
"out vec4 fColor;"
"uniform mat4 vMatrix;"
"void main(void)"
"{"
"gl_Position = vMatrix * vPosition;"
"fColor = vColor;"
"}";

char *fragSrc =
"#version 450 core\n"
"in vec4 fColor;"
"out vec4 color;"
"void main(void)"
"{"
"color = vec4(1.0, 0, 0, 1.0);"
"}";

GLfloat vPosition[6][4] = {
    { 0.25, -0.25, -0.7, 1.0 },
    { -0.25, -0.25, -0.7, 1.0 },
    { 0.25, 0.25, -0.7, 1.0 },
    { 0.1, -0.1, -0.8, 1.0 },
    { -0.1, -0.1, -0.8, 1.0 },
    { 0.1, 0.1, -0.8, 1.0 }
};

GLfloat vColor[6][4] = {
    { 1.0, 0, 0, 1.0 },
    { 0, 1.0, 0, 1.0 },
    { 0, 0, 1.0, 1.0 },
    { 1.0, 1.0, 0, 1.0 },
    { 0, 1.0, 1.0, 1.0 },
    { 1.0, 0, 1.0, 1.0 }
};

GLfloat vMatrix[16] = {
    1.0, 0, 0, 0,
    0, 1.0, 0, 0,
    0, 0, 1.0, 0,
    0, 0, 0, 1.0
};


void renderScene(void)
{
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    float q[48];
    glBindBuffer(GL_ARRAY_BUFFER, VBOs[0]);
    glGetBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(vPosition) + sizeof(vColor), q);
    for (int i = 0; i < 48; i++)
    {
        printf("%f\n", q[i]);
    }
    printf("\n");

    glEnable(GL_RASTERIZER_DISCARD);
    glBindVertexArray(VAOs[0]);
    glBindVertexBuffer(0, VBOs[0], 0, 4 * sizeof(GL_FLOAT));
    glBindTransformFeedback(GL_TRANSFORM_FEEDBACK, TFBs[0]);
    glBeginTransformFeedback(GL_TRIANGLES);
    glDrawArrays(GL_TRIANGLES, 3, 3);
    glDrawArrays(GL_TRIANGLES, 0, 3);
    glEndTransformFeedback();
    glBindTransformFeedback(GL_TRANSFORM_FEEDBACK, 0);
    glBindVertexArray(0);

    float p[48];
    glBindBuffer(GL_ARRAY_BUFFER, VBOs[1]);
    glGetBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(vPosition) + sizeof(vColor), p);
    for (int i = 0; i < 48; i++)
    {
        printf("%f\n", p[i]);
    }

    glDisable(GL_RASTERIZER_DISCARD);
    glBindVertexArray(VAOs[1]);
    glBindVertexBuffer(0, VBOs[1], 0, 8 * sizeof(GL_FLOAT));
    //glDrawArrays(GL_TRIANGLES, 3, 3);
    //glDrawArrays(GL_TRIANGLES, 0, 3);
    glDrawTransformFeedback(GL_TRIANGLES, TFBs[0]);
    glBindVertexArray(0);

    glutSwapBuffers();
    //glutPostRedisplay();
}

void Init()
{
    glEnable(GL_DEPTH_TEST);

    GLuint vert = glCreateShader(GL_VERTEX_SHADER);
    glShaderSource(vert, 1, &vertSrc, 0);
    glCompileShader(vert);

    GLuint frag = glCreateShader(GL_FRAGMENT_SHADER);
    glShaderSource(frag, 1, &fragSrc, 0);
    glCompileShader(frag);

    GLuint program = glCreateProgram();
    glAttachShader(program, vert);
    glAttachShader(program, frag);
    glLinkProgram(program);
    glUseProgram(program);


    GLint matrix = glGetUniformLocation(program, "vMatrix");
    glUniformMatrix4fv(matrix, 1, GL_TRUE, vMatrix);//second parameter indicates the number of matrices

    GLint position = glGetAttribLocation(program, "vPosition");
    GLint color = glGetAttribLocation(program, "vColor");

    glGenVertexArrays(2, VAOs);

    glBindVertexArray(VAOs[0]);
    glVertexAttribFormat(position, 4, GL_FLOAT, GL_FALSE, 0);
    glVertexAttribBinding(position, 0);
    glVertexAttribFormat(color, 4, GL_FLOAT, GL_FALSE, sizeof(vPosition));
    glVertexAttribBinding(color, 0);
    glEnableVertexAttribArray(position);
    glEnableVertexAttribArray(color);
    glBindVertexArray(0);

    glBindVertexArray(VAOs[1]);
    glVertexAttribFormat(position, 4, GL_FLOAT, GL_FALSE, 0);
    glVertexAttribBinding(position, 0);
    glVertexAttribFormat(color, 4, GL_FLOAT, GL_FALSE, 4 * sizeof(GL_FLOAT));
    glVertexAttribBinding(color, 0);
    glEnableVertexAttribArray(position);
    glEnableVertexAttribArray(color);
    glBindVertexArray(0);


    glGenBuffers(2, VBOs);

    glBindBuffer(GL_ARRAY_BUFFER, VBOs[0]);
    //glBufferStorage(GL_ARRAY_BUFFER, sizeof(vPosition) + sizeof(vColor), 0, 0);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vPosition) + sizeof(vColor), 0, GL_STATIC_DRAW);
    glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(vPosition), vPosition);
    glBufferSubData(GL_ARRAY_BUFFER, sizeof(vPosition), sizeof(vColor), vColor);
    glBindBuffer(GL_ARRAY_BUFFER, 0);

    glBindBuffer(GL_ARRAY_BUFFER, VBOs[1]);
    //glBufferStorage(GL_ARRAY_BUFFER, sizeof(vPosition) + sizeof(vColor), 0, 0);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vPosition) + sizeof(vColor), 0, GL_STREAM_READ);
    glBindBuffer(GL_ARRAY_BUFFER, 0);


    glGenTransformFeedbacks(1, TFBs);

    glBindTransformFeedback(GL_TRANSFORM_FEEDBACK, TFBs[0]);
    glBindBufferBase(GL_TRANSFORM_FEEDBACK_BUFFER, 0, VBOs[1]);
    glBindTransformFeedback(GL_TRANSFORM_FEEDBACK, 0);


    glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
}

int main(int argc, char **argv)
{
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DEPTH | GLUT_DOUBLE | GLUT_RGBA);
    glutInitWindowPosition(400, 300);
    glutInitWindowSize(800, 600);
    glutInitContextVersion(4, 5);
    glutInitContextProfile(GLUT_CORE_PROFILE);
    glutCreateWindow("Drawing my first triangle");
    glewInit();

    GLubyte const *v = glGetString(GL_VERSION);
    printf("%s\n", v);

    Init();

    // register callbacks
    glutDisplayFunc(renderScene);
    glutMainLoop();
    glDeleteProgram(program);
    return 0;
}