OpenGL rendering does not work correctly with OpenCV using GLSL shaders -

i have coded small opengl program using opengl , glsl shaders. here's screen of application :

now, objective mix opengl frame , 1 webcam in unique frame using opencv. before glsl shaders, tried make simple program drawing colored triangle basic opengl functions (glbengin, glvertex, etc.).

static int      initgl() {     if (!glfwinit())         return (-1);      if (!glfwopenwindow(500, 500, 8, 8, 8, 0, 24, 0, glfw_window)) {         glfwterminate();         return (-1);     }      glenable(gl_projection);     glloadidentity();     gluperspective(45.0f, 500.0f / 500.0f, 0.1f, 100.0f);     glulookat(0.0f, 0.0f, 5.0f, 0.0f, 0.0f, 0.0f, 0.0f, 1.0f, 0.0f);      return (0); }  static void     drawgl() {     glbegin(gl_triangles);     glcolor3ub(255, 0, 0);     glvertex3f(-1.0f, 0.0f, 0.0f);     glcolor3ub(0, 255, 0);     glvertex3f(0.0f, 1.0f, 0.0f);     glcolor3ub(0, 0, 255);     glvertex3f(1.0f, 0.0f, 0.0f);     glend(); }  int             main(void) {     initgl();      cvcapture   *capture = cvcapturefromcam(cv_cap_any);      if (!capture) {         fprintf(stderr, "error: capture null \n");         getchar();         return (-1);     }      while (1)     {         glclear(gl_color_buffer_bit);         glenable(gl_modelview);          iplimage    *frame = cvqueryframe(capture);          if (!frame) {             fprintf(stderr, "error: frame null...\n");             getchar();             break;         }          gldrawpixels(frame->width, frame->height, gl_rgb, gl_unsigned_byte, frame->imagedata);          drawgl();          glfwswapbuffers();          if ( (cvwaitkey(10) & 255) == 27 ) break;     }      cvreleasecapture(&capture);     cvdestroywindow("mywindow");      return (exit_success); } 

here's render :

as can see result correct. now, wanted try first program using glsl shaders opencv below when application launched have black screen. tried several tests , problem seems begin when call gluseprogram function (so when want bind program shader -> in code corresponds program->bind() call). here use gldrawpixels function load video frame. think it's not function call if want use glsl shaders. here's piece of c++ code :

[...]  /*my glsl shaders initialization*/  [...] int                         main(int ac, char **av) {     bool                    isalive = true;     unsigned int            vaoid = 0;     sdl_event               event;     gluint                  textureid = 0;     shaderprogram           *program = null;      if (!glfwinit())         return (-1);      if (!glfwopenwindow(width, height, 8, 8, 8, 0, 24, 0, glfw_window)) {         glfwterminate();         return (-1);     }      glenable(gl_depth_test);      //viewport initialization      glviewport(0, 0, width, height);      //vertex declaration      vertexdeclaration *vdeclar = initvertexdeclaration();      //glew init component      glewinit();      //vbo initialization      vertexbuffer *vbuffer = initvbo();      //shaders initialization      program = initshaders("triangle-pf.vert", "triangle-pf.frag");      //texture initialization      textureid = loadbmptexture("box.bmp");      //vao initialization      initvao(vaoid, vbuffer, textureid, vdeclar);      //screen capture initialization      cvcapture   *capture = cvcapturefromcam(cv_cap_any);      if (!capture) {         fprintf(stderr, "error: capture null \n");         getchar();         return (-1);     }      //main loop      while (isalive == true)     {         //eventlistener(&event, &isalive);          if (glfwgetkey(glfw_key_esc))             isalive = false;          glcleardepth(1.0f);         glclearcolor(0.13f, 0.12f, 0.13f, 1.0f);         glclear(gl_color_buffer_bit | gl_depth_buffer_bit);          //---------------------------------------------------          iplimage    *frame = cvqueryframe(capture);          if (!frame) {             fprintf(stderr, "error: frame null...\n");             getchar();             break;         }          //---------------------------------------------------          program->bind();          //projection matrix          glm::mat4 projectionmatrix = glm::perspective(45.0f, 500.0f / 500.0f, 0.1f, 100.0f);          //view matrix          glm::mat4 viewmatrix = glm::lookat(glm::vec3(0.0f, 0.0f, 8.0f), glm::vec3(0.0f, 0.0f, 0.0f), glm::vec3(0.0f, 1.0f, 0.0f));          //model matrix          glm::mat4 modelmatrix = glm::mat4(1.0f);         modelmatrix = glm::translate(modelmatrix, glm::vec3(0.0f, 0.0f, 0.0f));         modelmatrix = glm::rotate(modelmatrix, angle, glm::vec3(1.0f, 1.0f, 1.0f));         modelmatrix = glm::scale(modelmatrix, glm::vec3(1.0f, 1.0f, 1.0f));          //prepare matrix          glm::mat4 modelviewmatrix = viewmatrix * modelmatrix;         glm::mat3 normalmatrix = glm::mat3(glm::vec3(modelviewmatrix[0]), glm::vec3(modelviewmatrix[1]), glm::vec3(modelviewmatrix[2]));         glm::mat4 modelviewprojectionmatrix = projectionmatrix * modelviewmatrix;         glm::vec4 lightpositionvec1 = viewmatrix * glm::vec4(lightposition1[0], lightposition1[1], lightposition1[2], lightposition1[3]);          //send source light properties          program->setuniform("lightinfos[0].la", glm::vec3(0.000000f, 0.000000f, 0.000000f));         program->setuniform("lightinfos[0].ld", glm::vec3(0.800000f, 0.800000f, 0.800000f));         program->setuniform("lightinfos[0].ls", glm::vec3(1.000000f, 1.000000f, 1.000000f));         program->setuniform("lightinfos[0].le", glm::vec3(0.200000f, 0.200000f, 0.200000f));          /*program->setuniform("lightinfos[1].la", glm::vec3(0.000000f, 0.000000f, 0.000000f));         program->setuniform("lightinfos[1].ld", glm::vec3(0.800000f, 0.800000f, 0.800000f));         program->setuniform("lightinfos[1].ls", glm::vec3(0.000000f, 1.000000f, 1.000000f));         program->setuniform("lightinfos[1].le", glm::vec3(0.200000f, 0.200000f, 0.200000f));*/          //send model materials properties          program->setuniform("materialinfos.ka", glm::vec3(0.000000f, 0.000000f, 0.000000f));         program->setuniform("materialinfos.kd", glm::vec3(1.000000f, 1.000000f, 1.000000f));         program->setuniform("materialinfos.ks", glm::vec3(1.000000f, 1.000000f, 1.000000f));         program->setuniform("materialinfos.ke", glm::vec3(0.200000f, 0.000000f, 0.200000f));         program->setuniform("materialinfos.shininess", 10.0f);          //send light position          program->setuniform("lightinfos[0].position", lightpositionvec1);          //send matrix          program->setuniform("projectionmatrix", projectionmatrix);         program->setuniform("normalmatrix", normalmatrix);         program->setuniform("modelviewmatrix", modelviewmatrix);         program->setuniform("modelmatrix", modelmatrix);         program->setuniform("mvp", modelviewprojectionmatrix);          gldrawpixels(frame->width, frame->height, gl_rgb, gl_unsigned_byte, frame->imagedata);          //vao binding          glbindvertexarray(vaoid);          //render meshes          gldrawarrays(gl_triangles, 0, vbuffer->getsize());          glbindvertexarray(0);          program->release();          angle += 0.50f;          glflush();         glfwswapbuffers();     }      unsigned int vboid = vbuffer->gethandle();     gldeletebuffers(1, &vboid);     gldeletevertexarrays(1, &vaoid);     return (0); } 

so think problem comes gldrawpixels cannot used glsl shaders. tried several possible ways without success. maybe have send video frame buffer directly pixel shader ? in case, how can ? i'm lost. can me?

the way set use image data texture. this link might starting point. can render quad in background, fills entire screen, , uses texture determine color of each pixel. advantage on gldrawpixels() if scale window (and quad), image video scaled accordingly.

if need to, can use texture in shader when rendering quad: fragment (pixel) shader gets called each pixel, , use sampler color texture. can modify color according lighting needs.

what draw on top of you.