c++ - nvolgv32.dll - glDrawElements trouble -

at moment im coding graphic app using opengl , im drawing obj files using gldrawelements. i've nvidia geforce gt 740m

the trouble : first-chance exception @ 0x68fcf460 (nvoglv32.dll) in demo.exe: 0xc0000005: access violation reading location 0x00000000. , dont know how can fix this.

these buffers initialization

    // <-- vbos ibo vao creation --> //      glgenbuffers(3, obj_vbo);     glgenbuffers(1, &obj_ibo);     glgenvertexarrays(1, &obj_vao);      // <-- ibo --> //      glbindbuffer(gl_element_array_buffer, obj_ibo);     glbufferdata(gl_element_array_buffer, obj_triangles.size() * sizeof(glushort), obj_triangles.data(), gl_static_draw);     glbindbuffer(gl_element_array_buffer, null);      // <-- vao --> //      glbindvertexarray(obj_vao);          glenablevertexattribarray(vertex_layout);         glbindbuffer(gl_array_buffer, obj_vbo[vertex_layout]);         glbufferdata(gl_array_buffer, obj_vertices.size() * sizeof(glfloat), obj_vertices.data(), gl_static_draw);         glvertexattribpointer(vertex_layout, 3, gl_float, gl_false, gl_false, (glubyte *) null);         glbindbuffer(gl_array_buffer, null);         gldisablevertexattribarray(vertex_layout);          glenablevertexattribarray(normal_layout);         glbindbuffer(gl_array_buffer, obj_vbo[normal_layout]);         glbufferdata(gl_array_buffer, obj_normals.size() * sizeof(glfloat), obj_normals.data(), gl_static_draw);         glvertexattribpointer(normal_layout, 3, gl_float, gl_false, gl_false, (glubyte *) null);         glbindbuffer(gl_array_buffer, null);         gldisablevertexattribarray(normal_layout);          glenablevertexattribarray(texture_layout);         glbindbuffer(gl_array_buffer, obj_vbo[texture_layout]);         glbufferdata(gl_array_buffer, obj_textures.size() * sizeof(glfloat), obj_textures.data(), gl_static_draw);         glvertexattribpointer(texture_layout, 2, gl_float, gl_false, gl_false, (glubyte *) null);         glbindbuffer(gl_array_buffer, null);         gldisablevertexattribarray(texture_layout);      glbindvertexarray(null);      // <-- save , calculate stuffs . . . --> //      obj_triangles_size = (gluint) obj_triangles.size(); 

and draw method, vertex_layout = 0, normal_layout = 1, texture_layout = 2

    glbindvertexarray(obj_vao);          glenablevertexattribarray(vertex_layout);         glenablevertexattribarray(normal_layout);         glenablevertexattribarray(texture_layout);              glbindbuffer(gl_element_array_buffer, obj_ibo);             gldrawelements(gl_triangles, obj_triangles_size, gl_unsigned_short, null);             glbindbuffer(gl_element_array_buffer, null);          gldisablevertexattribarray(texture_layout);         gldisablevertexattribarray(normal_layout);         gldisablevertexattribarray(vertex_layout);      glbindvertexarray(null); 

if use option (auto-select) on nvidia panel / manage 3d settings app renders when switch option high-performance nvidia processor gives problem.

disclaimer:

   this not answer, explaining in comments impossible.

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here how vaos intended used, track of states redundantly changing every time draw.

initialization:

// <-- vbos ibo vao creation --> //  glgenbuffers(3, obj_vbo); glgenbuffers(1, &obj_ibo); glgenvertexarrays(1, &obj_vao);  // <-- vao --> //  glbindvertexarray(obj_vao);      // <-- ibo (moved) --> //      glbindbuffer(gl_element_array_buffer, obj_ibo);     glbufferdata(gl_element_array_buffer, obj_triangles.size() * sizeof(glushort), obj_triangles.data(), gl_static_draw);     // glbindbuffer(gl_element_array_buffer, null); -- remove      glenablevertexattribarray(vertex_layout);     glbindbuffer(gl_array_buffer, obj_vbo[vertex_layout]);     glbufferdata(gl_array_buffer, obj_vertices.size() * sizeof(glfloat), obj_vertices.data(), gl_static_draw);     glvertexattribpointer(vertex_layout, 3, gl_float, gl_false, gl_false, (glubyte *) null);     //glbindbuffer(gl_array_buffer, null);        -- remove     //gldisablevertexattribarray(vertex_layout);  -- remove      glenablevertexattribarray(normal_layout);     glbindbuffer(gl_array_buffer, obj_vbo[normal_layout]);     glbufferdata(gl_array_buffer, obj_normals.size() * sizeof(glfloat), obj_normals.data(), gl_static_draw);     glvertexattribpointer(normal_layout, 3, gl_float, gl_false, gl_false, (glubyte *) null);     //glbindbuffer(gl_array_buffer, null);        -- remove     ///gldisablevertexattribarray(normal_layout); -- remove      glenablevertexattribarray(texture_layout);     glbindbuffer(gl_array_buffer, obj_vbo[texture_layout]);     glbufferdata(gl_array_buffer, obj_textures.size() * sizeof(glfloat), obj_textures.data(), gl_static_draw);     glvertexattribpointer(texture_layout, 2, gl_float, gl_false, gl_false, (glubyte *) null);     //glbindbuffer(gl_array_buffer, null);        -- remove     //gldisablevertexattribarray(texture_layout); -- remove  glbindvertexarray(null);  // <-- save , calculate stuffs . . . --> //  obj_triangles_size = (gluint) obj_triangles.size(); 

drawing:

glbindvertexarray(obj_vao);      //glenablevertexattribarray(vertex_layout);  -- remove     //glenablevertexattribarray(normal_layout);  -- remove     //glenablevertexattribarray(texture_layout); -- remove          //glbindbuffer(gl_element_array_buffer, obj_ibo); -- remove         gldrawelements(gl_triangles, obj_triangles_size, gl_unsigned_short, null);         //glbindbuffer(gl_element_array_buffer, null);    -- remove      //gldisablevertexattribarray(texture_layout); -- remove     //gldisablevertexattribarray(normal_layout);  -- remove     //gldisablevertexattribarray(vertex_layout);  -- remove  glbindvertexarray(null);