Invalid operation error from GL when using FBO

OpenGL OpenGL: Basic Coding
1 

/*Create a offscreen FBO*/
	glGenRenderbuffersEXT(1, &fbo);
	/*Bind offscreen framebuffer*/ 
    	glBindRenderbufferEXT(GL_RENDERBUFFER_EXT, fbo);
	glRenderbufferStorageEXT(GL_RENDERBUFFER_EXT,GL_RGBA,size,noOfpacket);
	glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT,GL_COLOR_ATTACHMENT0_EXT,GL_RENDERBUFFER_EXT,fbo);
	checkError("glFramebufferRenderbufferEXT");
	
	GLenum status1;
  	status1 = glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT);
  	switch(status1)
  	{
     		case GL_FRAMEBUFFER_COMPLETE_EXT:
     			printf("OK
");
			break;
  		default:
     			fprintf(stderr, "Error: %s
", gluErrorString(status1));
			break;
 	 }

I double check already. I very sure that the GL error comes from this function. I even use glCheckFramebufferStatusEXT() to check the FBO status and it returns “OK”.

What is going on actually? I cant even find out the error. Please help…

2

From your thread here you’ve got an Intel 945.

The Intel 945 doesn’t support FBOs.

3

Are you sure? I check the glxinfo already.

root@goo5257-laptop:~# glxinfo
name of display: :0.0
display: :0 screen: 0
direct rendering: Yes
server glx vendor string: Brian Paul
server glx version string: 1.4 Mesa 7.7.1
server glx extensions:
GLX_MESA_copy_sub_buffer, GLX_MESA_pixmap_colormap,
GLX_MESA_release_buffers, GLX_ARB_get_proc_address,
GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info, GLX_EXT_visual_rating,
GLX_SGIX_fbconfig, GLX_SGIX_pbuffer
client glx vendor string: Brian Paul
client glx version string: 1.4 Mesa 7.7.1
client glx extensions:
GLX_MESA_copy_sub_buffer, GLX_MESA_pixmap_colormap,
GLX_MESA_release_buffers, GLX_ARB_get_proc_address,
GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info, GLX_EXT_visual_rating,
GLX_SGIX_fbconfig, GLX_SGIX_pbuffer
GLX version: 1.4
GLX extensions:
GLX_MESA_copy_sub_buffer, GLX_MESA_pixmap_colormap,
GLX_MESA_release_buffers, GLX_ARB_get_proc_address,
GLX_EXT_texture_from_pixmap, GLX_EXT_visual_info, GLX_EXT_visual_rating,
GLX_SGIX_fbconfig, GLX_SGIX_pbuffer
OpenGL vendor string: Brian Paul
OpenGL renderer string: Mesa X11
OpenGL version string: 2.1 Mesa 7.7.1
OpenGL shading language version string: 1.20
OpenGL extensions:
GL_EXT_compiled_vertex_array, GL_EXT_texture_env_add, GL_ARB_copy_buffer,
GL_ARB_depth_texture, GL_ARB_depth_clamp, GL_ARB_draw_buffers,
GL_ARB_draw_elements_base_vertex, GL_ARB_fragment_program,
GL_ARB_fragment_program_shadow, GL_ARB_fragment_shader,
GL_ARB_framebuffer_object, GL_ARB_half_float_pixel, GL_ARB_imaging,
GL_ARB_map_buffer_range, GL_ARB_multisample, GL_ARB_multitexture,
GL_ARB_occlusion_query, GL_ARB_pixel_buffer_object,
GL_ARB_point_parameters, GL_ARB_point_sprite, GL_ARB_provoking_vertex,
GL_ARB_shader_objects, GL_ARB_shading_language_100,
GL_ARB_shading_language_120, GL_ARB_shadow, GL_ARB_shadow_ambient,
GL_ARB_sync, GL_ARB_texture_border_clamp, GL_ARB_texture_compression,
GL_ARB_texture_cube_map, GL_ARB_texture_env_add,
GL_ARB_texture_env_combine, GL_ARB_texture_env_crossbar,
GL_ARB_texture_env_dot3, GL_ARB_texture_mirrored_repeat,
GL_ARB_texture_non_power_of_two, GL_ARB_texture_rectangle,
GL_ARB_transpose_matrix, GL_ARB_vertex_array_bgra,
GL_ARB_vertex_array_object, GL_ARB_vertex_buffer_object,
GL_ARB_vertex_program, GL_ARB_vertex_shader, GL_ARB_window_pos,
GL_EXT_abgr, GL_EXT_bgra, GL_EXT_blend_color,
GL_EXT_blend_equation_separate, GL_EXT_blend_func_separate,
GL_EXT_blend_logic_op, GL_EXT_blend_minmax, GL_EXT_blend_subtract,
GL_EXT_convolution, GL_EXT_copy_texture, GL_EXT_depth_bounds_test,
GL_EXT_draw_range_elements, GL_EXT_framebuffer_blit,
GL_EXT_framebuffer_multisample, GL_EXT_framebuffer_object,
GL_EXT_fog_coord, GL_EXT_gpu_program_parameters, GL_EXT_histogram,
GL_EXT_multi_draw_arrays, GL_EXT_packed_depth_stencil,
GL_EXT_packed_pixels, GL_EXT_paletted_texture, GL_EXT_pixel_buffer_object,
GL_EXT_point_parameters, GL_EXT_polygon_offset, GL_EXT_provoking_vertex,
GL_EXT_rescale_normal, GL_EXT_secondary_color,
GL_EXT_separate_specular_color, GL_EXT_shadow_funcs,
GL_EXT_shared_texture_palette, GL_EXT_stencil_two_side,
GL_EXT_stencil_wrap, GL_EXT_subtexture, GL_EXT_texture, GL_EXT_texture3D,
GL_EXT_texture_cube_map, GL_EXT_texture_edge_clamp,
GL_EXT_texture_env_combine, GL_EXT_texture_env_dot3,
GL_EXT_texture_lod_bias, GL_EXT_texture_mirror_clamp,
GL_EXT_texture_object, GL_EXT_texture_rectangle, GL_EXT_texture_sRGB,
GL_EXT_texture_swizzle, GL_EXT_timer_query, GL_EXT_vertex_array,
GL_EXT_vertex_array_bgra, GL_3DFX_texture_compression_FXT1,
GL_APPLE_packed_pixels, GL_APPLE_vertex_array_object,
GL_ATI_blend_equation_separate, GL_ATI_envmap_bumpmap,
GL_ATI_texture_env_combine3, GL_ATI_texture_mirror_once,
GL_ATI_fragment_shader, GL_ATI_separate_stencil,
GL_IBM_multimode_draw_arrays, GL_IBM_rasterpos_clip,
GL_IBM_texture_mirrored_repeat, GL_INGR_blend_func_separate,
GL_MESA_pack_invert, GL_MESA_resize_buffers, GL_MESA_texture_array,
GL_MESA_ycbcr_texture, GL_MESA_window_pos, GL_NV_blend_square,
GL_NV_depth_clamp, GL_NV_fragment_program, GL_NV_fragment_program_option,
GL_NV_light_max_exponent, GL_NV_packed_depth_stencil, GL_NV_point_sprite,
GL_NV_texture_env_combine4, GL_NV_texture_rectangle,
GL_NV_texgen_reflection, GL_NV_vertex_program, GL_NV_vertex_program1_1,
GL_OES_read_format, GL_SGI_color_matrix, GL_SGI_color_table,
GL_SGI_texture_color_table, GL_SGIS_generate_mipmap,
GL_SGIS_texture_border_clamp, GL_SGIS_texture_edge_clamp,
GL_SGIS_texture_lod, GL_SUN_multi_draw_arrays

There it is.

4

By the sane token you should be using ARB frambuffer instead as that is a far better extension.

5

Are you quite certain that’s the Intel?

An Intel 945 is actually a software T&L part locked at OpenGL 1.4 (plus the ARB_vertex_buffer and EXT_shadow_funcs extensions - likely through software emulation - source: Intel website); whereever that extensions list is coming from I highly doubt that it’s the 945 driver.

6

You should generate a render first with glGenRenderBuffer.

You are binding the FBO ID as a render buffer and this do not make sense.
Your code should with something like:



// Generate a depth render buffer
GLuint depthBuffer;
glGenRenderbuffers( 1, &depthBuffer );
glBindRenderbuffer( GL_RENDERBUFFER, depthBuffer );
glRenderbufferStorage( GL_RENDERBUFFER, GL_DEPTH_COMPONENT, w, h );
glBindRenderbuffer( GL_RENDERBUFFER, 0 );

// Generate the frame buffer
GLuint fbo;
glGenFrameBuffer( 1, &fbo );
glBindFrameBuffer( fbo )

// Bind the depth render buffer to the frame buffer
glFramebufferRenderbuffer( GL_FRAMEBUFFER, GL_DEPTH_ATTACHMENT, GL_RENDERBUFFER, depthBuffer );

Be aware that you should attach a color buffer or texture to the frame buffer in order to get the render result.

7

Thanks. I got it.