Question

我有一个OpenGL应用程序，它显示一个相机框架，上面有一些3d元素。我想要做的是使用openGL来组合框架和元素，但然后使用OpenCv显示图像，而不是显示OpenGL窗口。这可能吗？

目前的代码是：

int main()
{
 // Init GLUT window
    glutInit(&argc, argv);
    glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA);

  // Create GLUT window
    glutInitWindowSize(wWnd, hWnd);
    glutCreateWindow("Mapping");

 // Initialize OpenGL
    int res = initGL();
    if (res != 0) {
        std::cout << "Failed to initialize OpenGL" << std::endl;       
        return -1;
    }

....

}

init函数的位置：

int initGL() {

    // Init glew after window has been created
    glewInit();
    glClearColor(0.0, 0.0, 0.0, 0.0);

    // Create and Register OpenGL Texture for Image (RGBA -- 4channels)
    glEnable(GL_TEXTURE_2D);
    glGenTextures(1, &imageTex);
    glBindTexture(GL_TEXTURE_2D, imageTex);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, wWnd, hWnd, 0, GL_BGRA_EXT, GL_UNSIGNED_BYTE, NULL);
    glBindTexture(GL_TEXTURE_2D, 0);
    cudaError_t err1 = cudaGraphicsGLRegisterImage(&cuda_gl_ressource, imageTex, GL_TEXTURE_2D, cudaGraphicsRegisterFlagsWriteDiscard);
    if (err1 != cudaError::cudaSuccess) return -1;

    // Create GLSL Shaders for Mesh and Image
    shader_mesh = new Shader((GLchar*) MESH_VERTEX_SHADER, (GLchar*) MESH_FRAGMENT_SHADER);
    shMVPMatrixLoc = glGetUniformLocation(shader_mesh->getProgramId(), "u_mvpMatrix");
    shColorLoc = glGetUniformLocation(shader_mesh->getProgramId(), "u_color");
    shader_image = new Shader((GLchar*) IMAGE_VERTEX_SHADER, (GLchar*) IMAGE_FRAGMENT_SHADER);
    texID = glGetUniformLocation(shader_image->getProgramId(), "texImage");

    // Create Frame Buffer for offline rendering
    // Here we render the composition of the image and the projection of the mesh on top of it in a texture (using FBO - Frame Buffer Object)
    glGenFramebuffers(1, &fbo);
    glBindFramebuffer(GL_FRAMEBUFFER, fbo);

    // Generate a render texture (which will contain the image and mesh in wireframe overlay)
    glGenTextures(1, &renderedTexture);
    glBindTexture(GL_TEXTURE_2D, renderedTexture);

    // Give an empty image to OpenGL ( the last "0" as pointer )
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, wWnd, hWnd, 0, GL_RGBA, GL_UNSIGNED_BYTE, 0);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);

    // Set "renderedTexture" as our color attachment #0
    glFramebufferTexture(GL_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, renderedTexture, 0);

    // Set the list of draw buffers.
    GLenum DrawBuffers[1] = {GL_COLOR_ATTACHMENT0};
    glDrawBuffers(1, DrawBuffers);

    // Always check that our framebuffer is ok
    if (glCheckFramebufferStatus(GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE) {
        std::cout << "invalid FrameBuffer" << std::endl;
        return -1;
    }

    glBindFramebuffer(GL_FRAMEBUFFER, 0);

    // Generate the Quad for showing the image in a full viewport
    static const GLfloat g_quad_vertex_buffer_data[] = {
        -1.0f, -1.0f, 0.0f,
        1.0f, -1.0f, 0.0f,
        -1.0f, 1.0f, 0.0f,
        -1.0f, 1.0f, 0.0f,
        1.0f, -1.0f, 0.0f,
        1.0f, 1.0f, 0.0f};

    // Color of wireframe (soft blue)
    vertices_color.r = 0.35f;
    vertices_color.g = 0.65f;
    vertices_color.b = 0.95f;

    // Generate a buffer to handle vertices for the GLSL shader
    glGenBuffers(1, &quad_vb);
    glBindBuffer(GL_ARRAY_BUFFER, quad_vb);
    glBufferData(GL_ARRAY_BUFFER, sizeof(g_quad_vertex_buffer_data), g_quad_vertex_buffer_data, GL_STATIC_DRAW);

    glutSetOption(GLUT_ACTION_ON_WINDOW_CLOSE, GLUT_ACTION_CONTINUE_EXECUTION);

    return 0;
}

我可以抓住framebuffer并将其转换为cv :: mat，我就可以了。我的问题是，如果没有GL Window，我似乎无法运行应用程序。如果我注释掉glutCreateWindow行，则init会失败。

是否可以在后台运行openGL而不显示窗口？谢谢。

C ++我可以在不看窗口的情况下使用OpenGL帧缓冲区吗？

0 个答案: