In T43987#295336, @Julian Eisel (Severin) wrote:

Could you upload a .blend so we can see what you are doing?

Yes.

@Bastien Montagne (mont29) Sorry, I'm new here.

@Campbell Barton (campbellbarton) Here's the blend file of the image.

Can't confirm that here. @Gabriel (KillerButter2K), could you place this dll into the folder that contains the blender.exe and test again? Will be slow but shows us if this possibly is a graphics driver issue or not.

You should press the buttons at the lower part of the 3D viewport that has the effect to make sure they are enabled. Doing it from the menu may not work.

Never mind. I just have a crappy graphics card. And it's not compatible for any drivers.

@Antonis Ryakiotakis (psy-fi) What do you mean? enable what?

Actually file works OK here (even invoking rendering from the menu) so it is probably a driver issue. Especially if trying using the dll by Julian works. If you have a graphics card not compatible with any drivers (which card is that by the way and why does it not support drivers?) then you are shooting yourself in the foot here.

@Antonis Ryakiotakis (psy-fi) I have an ATI Radeon HD 3600. It's pretty old.

This is the latest driver I can find. The HD 3600 seems to support OGL 3.2 so it should work.

@Julian Eisel (Severin) The DLL file works for both ambient occlusion and depth of field, but it's slow like crap. Is there a faster version of it?

The faster version is called driver. But drivers can have their own peculiarities and it's possible that Radeon's driver has a bug. We have a lot of reports on radeon 3xxx series unfortunately.

Alright, so I did some debugging on my Intel and it seems that the issue is that the derivatives calculated from the driver are the issue. Basically, the normals are flipped, and you get shading at the points instead of the cavities.

See this very old thread that describes the issue for ATI https://www.opengl.org/discussion_boards/showthread.php/164647-weird-dFdx-dFdy-on-ATI/page1

I made a bug report for Intel, but for ATI it's unlikely the issue will be addressed since support has been discontinued.

I could code workarounds for those GPUs basically we have to examine the driver and GPU strings and set a few factors accordingly to what each driver does. I'll have to ask other developers what they think about this...I don't like the solution too much but it will make those GPUs work at least.

To the reporter:

I will workaround this, but I need the contents of your system_info.txt file first (Go to help menu in blender, select system info, open the file from a text editor in blender)

@Antonis Ryakiotakis (psy-fi) Here's the system info

Blender 2.74 (sub 0) System Information

Blender:

version 2.74 (sub 0), branch b'master', commit date b'2015-03-24' b'15:31', hash b'8804e64', b'Release'
build date: b'2015-03-24', b'18:28:48'
platform: b'Windows:32bit'
binary path: 'C:\\Program Files\\Blender Foundation\\Blender\\blender-app.exe'
build cflags: b'-DWITH_FREESTYLE /nologo /J /W3 /Gd /w34062 /wd4018 /wd4065 /wd4127 /wd4181 /wd4200 /wd4244 /wd4267 /wd4305 /wd4800 /we4013 /we4431 /D_WIN32_WINNT=0x600 /DOIIO_STATIC_BUILD /openmp -O2 /Ob2 -DWIN32 -D_CONSOLE -D_LIB -D_CRT_SECURE_NO_DEPRECATE -DOPJ_STATIC -DWIN64 -DWITH_MOD_FLUID -DWITH_MOD_OCEANSIM -DLITTLE_ENDIAN -DWITH_AUDASPACE -DWITH_AVI -DWITH_OPENNL'
build cxxflags: b'/nologo /J /W3 /Gd /w34062 /wd4018 /wd4065 /wd4127 /wd4181 /wd4200 /wd4244 /wd4267 /wd4305 /wd4800 /we4013 /we4431 /D_WIN32_WINNT=0x600 /DOIIO_STATIC_BUILD /openmp /EHsc -O2 /Ob2 -DWIN32 -D_CONSOLE -D_LIB -D_CRT_SECURE_NO_DEPRECATE -DOPJ_STATIC -DWIN64 -DWITH_MOD_FLUID -DWITH_MOD_OCEANSIM -DLITTLE_ENDIAN -DWITH_AUDASPACE -DWITH_AVI -DWITH_OPENNL'
build linkflags: b'/SUBSYSTEM:CONSOLE /MACHINE:X64 /STACK:2097152 /OPT:NOREF /INCREMENTAL:NO /NODEFAULTLIB:msvcrt.lib /NODEFAULTLIB:msvcmrt.lib /NODEFAULTLIB:msvcurt.lib /NODEFAULTLIB:msvcrtd.lib'
build system: b'SCons'

Python:

version: 3.4.2 (default, Dec 7 2014, 18:21:18) [MSC v.1800 64 bit (AMD64)]
paths:
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\scripts\\addons_contrib'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\scripts\\addons'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\scripts\\startup'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\scripts\\modules'
'C:\\Program Files\\Blender Foundation\\Blender\\python34.zip'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\python\\DLLs'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\python\\lib'
'C:\\Program Files\\Blender Foundation\\Blender'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\python'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\python\\lib\\site-packages'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\scripts\\freestyle\\modules'
'C:\\Program Files\\Blender Foundation\\Blender\\2.74\\scripts\\addons\\modules'
'C:\\Users\\Kids\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\scripts\\addons\\modules'

Directories:

scripts: ['C:\\Program Files\\Blender Foundation\\Blender\\2.74\\scripts']
user scripts: 'C:\\Users\\Kids\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\scripts'
pref scripts: None
datafiles: 'C:\\Users\\Kids\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\datafiles\\'
config: 'C:\\Users\\Kids\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\config\\'
scripts : 'C:\\Users\\Kids\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\scripts\\'
autosave: 'C:\\Users\\Kids\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\autosave\\'
tempdir: 'C:\\Users\\Kids\\AppData\\Local\\Temp\\blender_a00856\\'

FFmpeg:

'avcodec':' ''55, 39, 101'
'avdevice':' ''55, 5, 100'
'avformat':' ''55, 19, 104'
'avutil':' ''52, 48, 101'
'swscale':' '' 2, 5, 101'

SDL

Version: 2.0.3
Loading method: linked (WITH_SDL_DYNLOAD=OFF)

Other Libraries:

OpenColorIO: 1, 0, 8
OpenImageIO: 1, 4, 16
OpenShadingLanguage: 1, 5, 11

OpenGL

renderer: 'ATI Radeon HD 3600 Series '
vendor: 'ATI Technologies Inc.'
version: '3.3.10750 Compatibility Profile Context'
extensions:

		'GL_AMDX_debug_output GL_AMDX_vertex_shader_tessellator'
		'GL_AMD_conservative_depth GL_AMD_debug_output'
		'GL_AMD_depth_clamp_separate GL_AMD_draw_buffers_blend'
		'GL_AMD_name_gen_delete GL_AMD_performance_monitor'
		'GL_AMD_sample_positions GL_AMD_shader_stencil_export'
		'GL_AMD_vertex_shader_tessellator GL_ARB_ES2_compatibility'
		'GL_ARB_blend_func_extended GL_ARB_color_buffer_float'
		'GL_ARB_copy_buffer GL_ARB_depth_buffer_float GL_ARB_depth_clamp'
		'GL_ARB_depth_texture GL_ARB_draw_buffers GL_ARB_draw_buffers_blend'
		'GL_ARB_draw_elements_base_vertex GL_ARB_draw_instanced'
		'GL_ARB_explicit_attrib_location GL_ARB_fragment_coord_conventions'
		'GL_ARB_fragment_program GL_ARB_fragment_program_shadow'
		'GL_ARB_fragment_shader GL_ARB_framebuffer_object'
		'GL_ARB_framebuffer_sRGB GL_ARB_geometry_shader4'
		'GL_ARB_get_program_binary GL_ARB_half_float_pixel'
		'GL_ARB_half_float_vertex GL_ARB_imaging GL_ARB_instanced_arrays'
		'GL_ARB_map_buffer_range GL_ARB_multisample GL_ARB_multitexture'
		'GL_ARB_occlusion_query GL_ARB_occlusion_query2'
		'GL_ARB_pixel_buffer_object GL_ARB_point_parameters GL_ARB_point_sprite'
		'GL_ARB_provoking_vertex GL_ARB_sampler_objects'
		'GL_ARB_seamless_cube_map GL_ARB_separate_shader_objects'
		'GL_ARB_shader_bit_encoding GL_ARB_shader_objects'
		'GL_ARB_shader_precision GL_ARB_shader_stencil_export'
		'GL_ARB_shader_texture_lod GL_ARB_shading_language_100 GL_ARB_shadow'
		'GL_ARB_shadow_ambient GL_ARB_sync GL_ARB_texture_border_clamp'
		'GL_ARB_texture_buffer_object GL_ARB_texture_buffer_object_rgb32'
		'GL_ARB_texture_compression GL_ARB_texture_compression_rgtc'
		'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_float'
		'GL_ARB_texture_mirrored_repeat GL_ARB_texture_multisample'
		'GL_ARB_texture_non_power_of_two GL_ARB_texture_rectangle'
		'GL_ARB_texture_rg GL_ARB_texture_rgb10_a2ui GL_ARB_texture_snorm'
		'GL_ARB_timer_query GL_ARB_transform_feedback2'
		'GL_ARB_transform_feedback3 GL_ARB_transpose_matrix'
		'GL_ARB_uniform_buffer_object 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_vertex_type_2_10_10_10_rev GL_ARB_viewport_array'
		'GL_ARB_window_pos GL_ATI_draw_buffers GL_ATI_envmap_bumpmap'
		'GL_ATI_fragment_shader GL_ATI_meminfo GL_ATI_separate_stencil'
		'GL_ATI_texture_compression_3dc GL_ATI_texture_env_combine3'
		'GL_ATI_texture_float GL_ATI_texture_mirror_once GL_EXT_abgr'
		'GL_EXT_bgra GL_EXT_bindable_uniform GL_EXT_blend_color'
		'GL_EXT_blend_equation_separate GL_EXT_blend_func_separate'
		'GL_EXT_blend_minmax GL_EXT_blend_subtract GL_EXT_compiled_vertex_array'
		'GL_EXT_copy_buffer GL_EXT_copy_texture GL_EXT_direct_state_access'
		'GL_EXT_draw_buffers2 GL_EXT_draw_instanced GL_EXT_draw_range_elements'
		'GL_EXT_fog_coord GL_EXT_framebuffer_blit'
		'GL_EXT_framebuffer_multisample GL_EXT_framebuffer_object'
		'GL_EXT_framebuffer_sRGB GL_EXT_geometry_shader4'
		'GL_EXT_gpu_program_parameters GL_EXT_gpu_shader4 GL_EXT_histogram'
		'GL_EXT_multi_draw_arrays GL_EXT_packed_depth_stencil'
		'GL_EXT_packed_float GL_EXT_packed_pixels GL_EXT_pixel_buffer_object'
		'GL_EXT_point_parameters GL_EXT_provoking_vertex GL_EXT_rescale_normal'
		'GL_EXT_secondary_color GL_EXT_separate_specular_color'
		'GL_EXT_shadow_funcs GL_EXT_stencil_wrap GL_EXT_subtexture'
		'GL_EXT_texgen_reflection GL_EXT_texture3D GL_EXT_texture_array'
		'GL_EXT_texture_buffer_object GL_EXT_texture_compression_latc'
		'GL_EXT_texture_compression_rgtc GL_EXT_texture_compression_s3tc'
		'GL_EXT_texture_cube_map GL_EXT_texture_edge_clamp'
		'GL_EXT_texture_env_add GL_EXT_texture_env_combine'
		'GL_EXT_texture_env_dot3 GL_EXT_texture_filter_anisotropic'
		'GL_EXT_texture_integer GL_EXT_texture_lod 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_shared_exponent GL_EXT_texture_snorm'
		'GL_EXT_texture_swizzle GL_EXT_timer_query GL_EXT_transform_feedback'
		'GL_EXT_vertex_array GL_EXT_vertex_array_bgra'
		'GL_IBM_texture_mirrored_repeat GL_KTX_buffer_region GL_NV_blend_square'
		'GL_NV_conditional_render GL_NV_copy_depth_to_color'
		'GL_NV_explicit_multisample GL_NV_float_buffer GL_NV_half_float'
		'GL_NV_primitive_restart GL_NV_texgen_reflection GL_NV_texture_barrier'
		'GL_SGIS_generate_mipmap GL_SGIS_texture_edge_clamp GL_SGIS_texture_lod'
		'GL_SUN_multi_draw_arrays GL_WIN_swap_hint WGL_EXT_swap_control'

Implementation Dependent OpenGL Limits:

Maximum Fixed Function Texture Units: 8

GLSL:
Maximum Varying Floats: 128
Maximum Vertex Attributes: 29
Maximum Vertex Uniform Components: 16384
Maximum Fragment Uniform Components: 16384
Maximum Vertex Image Units: 16
Maximum Fragment Image Units: 16
Maximum Pipeline Image Units: 32

Cycles

CPU device capabilities: SSE2 SSE3 SSE41

this works for me but is different than in the view port

Bumped the effect up for more visibility

Awesome, thanks, that's exactly what I expected, will fix it soon.

Just a note, I have filed a bug report for Intel cards here

https://software.intel.com/en-us/forums/topic/543976

but I should be able to patch this even if they don't accept this as a bug.

Fixed this for the ATI case, will need Aaron's System_Info.txt as well to fix for Intel

Blender 2.74 (sub 2) System Information

Blender:

version 2.74 (sub 2), branch b'master', commit date b'2015-03-26' b'01:45', hash b'770b109', b'Release'
build date: b'2015-03-26', b'04:46:28'
platform: b'Windows:64bit'
binary path: 'C:\\Users\\AaronDownloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\blender-app.exe'
build cflags: b'-DWITH_FREESTYLE /nologo /J /W3 /Gd /w34062 /wd4018 /wd4065 /wd4127 /wd4181 /wd4200 /wd4244 /wd4267 /wd4305 /wd4800 /we4013 /we4431 /D_WIN32_WINNT=0x600 /DOIIO_STATIC_BUILD /openmp -O2 /Ob2 -DWIN32 -D_CONSOLE -D_LIB -D_CRT_SECURE_NO_DEPRECATE -DOPJ_STATIC -DWIN64 -DWITH_MOD_FLUID -DWITH_MOD_OCEANSIM -DLITTLE_ENDIAN -DWITH_AUDASPACE -DWITH_AVI -DWITH_OPENNL'
build cxxflags: b'/nologo /J /W3 /Gd /w34062 /wd4018 /wd4065 /wd4127 /wd4181 /wd4200 /wd4244 /wd4267 /wd4305 /wd4800 /we4013 /we4431 /D_WIN32_WINNT=0x600 /DOIIO_STATIC_BUILD /openmp /EHsc -O2 /Ob2 -DWIN32 -D_CONSOLE -D_LIB -D_CRT_SECURE_NO_DEPRECATE -DOPJ_STATIC -DWIN64 -DWITH_MOD_FLUID -DWITH_MOD_OCEANSIM -DLITTLE_ENDIAN -DWITH_AUDASPACE -DWITH_AVI -DWITH_OPENNL'
build linkflags: b'/SUBSYSTEM:CONSOLE /MACHINE:X64 /STACK:2097152 /OPT:NOREF /INCREMENTAL:NO /NODEFAULTLIB:msvcrt.lib /NODEFAULTLIB:msvcmrt.lib /NODEFAULTLIB:msvcurt.lib /NODEFAULTLIB:msvcrtd.lib'
build system: b'SCons'

Python:

version: 3.4.2 (default, Dec 7 2014, 18:21:18) [MSC v.1800 64 bit (AMD64)]
paths:
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\scripts\\addons_contrib'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\scripts\\addons'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\scripts\\startup'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\scripts\\modules'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\python34.zip'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\python\\DLLs'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\python\\lib'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\python'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\python\\lib\\site-packages'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\scripts\\freestyle\\modules'
'C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\scripts\\addons\\modules'
'C:\\Users\\Aaron\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\scripts\\addons\\modules'

Directories:

scripts: ['C:\\Users\\Aaron\\Downloads\\blender-2.74-770b109-win64\\blender-2.74-770b109-win64\\2.74\\scripts']
user scripts: 'C:\\Users\\Aaron\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\scripts'
pref scripts: None
datafiles: 'C:\\Users\\Aaron\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\datafiles\\'
config: 'C:\\Users\\Aaron\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\config\\'
scripts : 'C:\\Users\\Aaron\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\scripts\\'
autosave: 'C:\\Users\\Aaron\\AppData\\Roaming\\Blender Foundation\\Blender\\2.74\\autosave\\'
tempdir: 'C:\\Users\\Aaron\\AppData\\Local\\Temp\\blender_a05556\\'

FFmpeg:

'avcodec':' ''55, 39, 101'
'avdevice':' ''55, 5, 100'
'avformat':' ''55, 19, 104'
'avutil':' ''52, 48, 101'
'swscale':' '' 2, 5, 101'

SDL

Version: 2.0.3
Loading method: linked (WITH_SDL_DYNLOAD=OFF)

Other Libraries:

OpenColorIO: 1, 0, 8
OpenImageIO: 1, 4, 16
OpenShadingLanguage: 1, 5, 11

OpenGL

renderer: 'Intel(R) HD Graphics 4600'
vendor: 'Intel'
version: '4.0.0 - Build 9.18.10.3165'
extensions:

		'GL_EXT_blend_minmax GL_EXT_blend_subtract GL_EXT_blend_color'
		'GL_EXT_abgr GL_EXT_texture3D GL_EXT_clip_volume_hint'
		'GL_EXT_compiled_vertex_array GL_SGIS_texture_edge_clamp'
		'GL_SGIS_generate_mipmap GL_EXT_draw_range_elements GL_SGIS_texture_lod'
		'GL_EXT_rescale_normal GL_EXT_packed_pixels GL_EXT_texture_edge_clamp'
		'GL_EXT_separate_specular_color GL_ARB_multitexture'
		'GL_ARB_map_buffer_alignment GL_ARB_conservative_depth'
		'GL_EXT_texture_env_combine GL_EXT_bgra GL_EXT_blend_func_separate'
		'GL_EXT_secondary_color GL_EXT_fog_coord GL_EXT_texture_env_add'
		'GL_ARB_texture_cube_map GL_ARB_transpose_matrix'
		'GL_ARB_internalformat_query GL_ARB_texture_env_add'
		'GL_IBM_texture_mirrored_repeat GL_EXT_multi_draw_arrays'
		'GL_SUN_multi_draw_arrays GL_NV_blend_square GL_ARB_texture_compression'
		'GL_3DFX_texture_compression_FXT1 GL_EXT_texture_filter_anisotropic'
		'GL_ARB_texture_border_clamp GL_ARB_point_parameters'
		'GL_ARB_texture_env_combine GL_ARB_texture_env_dot3'
		'GL_ARB_texture_env_crossbar GL_EXT_texture_compression_s3tc'
		'GL_ARB_shadow GL_ARB_window_pos GL_EXT_shadow_funcs'
		'GL_EXT_stencil_wrap GL_ARB_vertex_program GL_EXT_texture_rectangle'
		'GL_ARB_fragment_program GL_EXT_stencil_two_side'
		'GL_ATI_separate_stencil GL_ARB_vertex_buffer_object'
		'GL_EXT_texture_lod_bias GL_ARB_occlusion_query GL_ARB_fragment_shader'
		'GL_ARB_shader_objects GL_ARB_shading_language_100'
		'GL_ARB_texture_non_power_of_two GL_ARB_vertex_shader'
		'GL_NV_texgen_reflection GL_ARB_point_sprite'
		'GL_ARB_fragment_program_shadow GL_EXT_blend_equation_separate'
		'GL_ARB_depth_texture GL_ARB_texture_rectangle GL_ARB_draw_buffers'
		'GL_ARB_color_buffer_float GL_ARB_half_float_pixel GL_ARB_texture_float'
		'GL_ARB_pixel_buffer_object GL_EXT_framebuffer_object'
		'GL_ARB_draw_instanced GL_ARB_half_float_vertex GL_ARB_occlusion_query2'
		'GL_EXT_draw_buffers2 GL_WIN_swap_hint GL_EXT_texture_sRGB'
		'GL_ARB_multisample GL_EXT_packed_float GL_EXT_texture_shared_exponent'
		'GL_ARB_texture_rg GL_ARB_texture_compression_rgtc'
		'GL_NV_conditional_render GL_EXT_texture_swizzle GL_ARB_texture_gather'
		'GL_ARB_sync GL_ARB_framebuffer_sRGB GL_EXT_packed_depth_stencil'
		'GL_ARB_depth_buffer_float GL_EXT_transform_feedback'
		'GL_ARB_transform_feedback2 GL_ARB_draw_indirect'
		'GL_EXT_framebuffer_blit GL_EXT_framebuffer_multisample'
		'GL_ARB_framebuffer_object GL_EXT_texture_array GL_EXT_texture_integer'
		'GL_ARB_map_buffer_range GL_EXT_texture_snorm'
		'GL_ARB_blend_func_extended GL_INTEL_performance_queries'
		'GL_ARB_copy_buffer GL_ARB_sampler_objects GL_NV_primitive_restart'
		'GL_ARB_seamless_cube_map GL_ARB_uniform_buffer_object'
		'GL_ARB_depth_clamp GL_ARB_vertex_array_bgra GL_ARB_shader_bit_encoding'
		'GL_ARB_draw_buffers_blend GL_ARB_geometry_shader4'
		'GL_EXT_geometry_shader4 GL_ARB_texture_query_lod'
		'GL_ARB_explicit_attrib_location GL_ARB_draw_elements_base_vertex'
		'GL_ARB_instanced_arrays GL_ARB_base_instance'
		'GL_ARB_fragment_coord_conventions GL_EXT_gpu_program_parameters'
		'GL_ARB_texture_buffer_object_rgb32 GL_ARB_compatibility'
		'GL_ARB_texture_rgb10_a2ui GL_ARB_texture_multisample'
		'GL_ARB_vertex_type_2_10_10_10_rev GL_ARB_timer_query'
		'GL_ARB_tessellation_shader GL_ARB_vertex_array_object'
		'GL_ARB_provoking_vertex GL_ARB_sample_shading'
		'GL_ARB_texture_cube_map_array GL_ARB_gpu_shader5'
		'GL_ARB_gpu_shader_fp64 GL_ARB_shader_subroutine'
		'GL_ARB_transform_feedback3 GL_ARB_transform_feedback_instanced'
		'GL_EXT_texture_storage GL_ARB_texture_storage GL_INTEL_map_texture'
		'GL_ARB_ES2_compatibility '

Implementation Dependent OpenGL Limits:

Maximum Fixed Function Texture Units: 8

GLSL:
Maximum Varying Floats: 64
Maximum Vertex Attributes: 16
Maximum Vertex Uniform Components: 4096
Maximum Fragment Uniform Components: 4096
Maximum Vertex Image Units: 16
Maximum Fragment Image Units: 16
Maximum Pipeline Image Units: 80

Cycles

CPU device capabilities: SSE2 SSE3 SSE41 AVX AVX2

Hi Antony,

Since this task is closed as "Resolved", would you like me to comment here or open a new report?

Thanks,

David

Well if this issue was not fixed then here but if it is a different bug then always a new report

yes, report here please

I think he was talking. About T44594

Thanks Aaron. Was referring to this issue, just takes me a long time to type and correct mistakes due to dyslexia.

Hi Antony,

Been testing this and have some feedback, first some system information.

Windows 7 x64
GNU/Linux Mint x64 Cinnamon
HD 3000
HD 4000
GTX 580m

Blender versions tested
2.74 x64 (000dfc0) Windows and GNU/Linux
2.74.3 x64 (883663a) Windows
2.74.5 (4288ab1) Windows and GNU/Linux
2.74.5 gooseberry (e4b1b17) Windows and GNU/Linux
2.74.5 gooseberry (920aa5e) Windows and GNU/Linux

My test .blend

Noticed the same issue under Windows 7 while using the Intel HD 3000, Viewport Ambient Occlusion is reversed with official 2.74 (and recent 2.74.5 versions, more on that in a moment) compared to OpenGL render.

Out of interest, if Intel driver related, why does enabling 'Depth Of Field' correct the reversed Ambient Occlusion (Viewport)? With DoF enabled, both Viewport and OpenGL render are identical in official 2.74 x64 (000dfc0) under Windows. Also, I believe GNU/Linux Mint uses the open source Intel driver and does not exhibit the same issue? This is certainly not a complaint, just interested to learn why. Thank you, appreciate your great Blender additions.

Official 2.74 (000dfc0) without 'Depth Of Field'

Official 2.74 (000dfc0) with 'Depth Of Field'

Noticed you applied a fix for Intel HD 3000 and HD 4000 graphics cards in version 2.74.3 x64 (883663a) for Windows, this fix no longer has effect in recent 2.74.5 versions, AO is once again reversed (just in the Viewport) unless Depth Of Field is enabled.

After several tests, the AO reversed issue only seems to affect an Optimus Laptop while using the Intel card under Windows. A desktop system with an Intel HD 4000 displays the Viewport AO correctly in official 2.74 (000dfc0) without a fix in place, also in 2.74.5 (4288ab1) while running under Windows.

On a slightly different note.
With Viewport Shading set to 'Texture', notice Viewport AO remains enabled after selecting 'Shadeless', is that the expected behavior, or should AO be disabled while Shadeless is activated?

Thank you for your time.

David

Can you attach your system_info.txt file please? I'll add your GPU/driver as an exception to our GPU detection module.

Re: shadeless: Yes, shadeless does not influence full screen effects like Ambient occlusion, this is expected.

Sorry for not being able to get back to you sooner.

Spent time trying to identify the cause and understand why AO will work correctly when DoF is enabled, or while creating an OpenGL render.

After many tests, including disabling my NVIDIA card and looking at different Intel drivers, sadly I'm no closer to understanding.

Based upon my previous finding, that adding DoF fixes AO reversal issue with a problematic Intel card, rather than adding a fix for some Intel cards to reverse the viewport AO effect, which then also incorrectly reverses an OpenGL render (please see below images), would it be possible to add an unseen null transform, for example a DoF but with with a large distance setting or f/stop (see below image tests)?

Hope these images help explain.

Below, without fix - Blender official 2.74 (Hash 000dfc0)
Viewport AO, laptop HD 3000

OpenGL render AO, laptop HD 3000

.
.

Below, with previous fix - Blender 2.74-3 (Hash 883663a)
Viewport AO, laptop HD 3000

OpenGL render AO, laptop HD 3000 (fix breaks OpenGL render)

.
.

Below, with null DoF (distance 100) - Blender official 2.74 (Hash 000dfc0)
Viewport AO, laptop HD 3000

OpenGL render AO, laptop HD 3000

Thank you

David

In T43987#306735, @Antonis Ryakiotakis (psy-fi) wrote:

Re: shadeless: Yes, shadeless does not influence full screen effects like Ambient occlusion, this is expected.

Thanks for explaining. Assumed shadeless would naturally disable all shading effects (including AO). Shadeless is useful for viewing baked Cycles textures where further AO is not necessary.

David

Hi this is an Intel driver bug, if you search this thread there's even a bug report to Intel, where they have promptly reported what the status is:

https://software.intel.com/en-us/forums/topic/543976

TL:DR version, in new drivers it's fixed and we have to patch it for old drivers, so I really need that system_info.txt please.

Thanks for your rapid reply.

I did read your Intel bug report (but rather embarrassingly due to the broad light blue bottom bar completely missed Intel's follow-up replies) and understood it was driver related. From an end users perspective, I was just trying to understand how with the same troublesome driver, enabling DoF fixed the AO issue, and why OpenGL render seemed unaffected.

OpenGL
============================================

renderer:	'Intel(R) HD Graphics 3000'
vendor:		'Intel'
version:	'3.1.0 - Build 9.17.10.4101'
extensions:
		'GL_EXT_blend_minmax GL_EXT_blend_subtract GL_EXT_blend_color'
		'GL_EXT_abgr GL_EXT_texture3D GL_EXT_clip_volume_hint'
		'GL_EXT_compiled_vertex_array GL_SGIS_texture_edge_clamp'
		'GL_SGIS_generate_mipmap GL_EXT_draw_range_elements GL_SGIS_texture_lod'
		'GL_EXT_rescale_normal GL_EXT_packed_pixels GL_EXT_texture_edge_clamp'
		'GL_EXT_separate_specular_color GL_ARB_multitexture'
		'GL_EXT_texture_env_combine GL_EXT_bgra GL_EXT_blend_func_separate'
		'GL_EXT_secondary_color GL_EXT_fog_coord GL_EXT_texture_env_add'
		'GL_ARB_texture_cube_map GL_ARB_transpose_matrix GL_ARB_texture_env_add'
		'GL_IBM_texture_mirrored_repeat GL_EXT_multi_draw_arrays'
		'GL_NV_blend_square GL_ARB_texture_compression'
		'GL_3DFX_texture_compression_FXT1 GL_EXT_texture_filter_anisotropic'
		'GL_ARB_texture_border_clamp GL_ARB_point_parameters'
		'GL_ARB_texture_env_combine GL_ARB_texture_env_dot3'
		'GL_ARB_texture_env_crossbar GL_EXT_texture_compression_s3tc'
		'GL_ARB_shadow GL_ARB_window_pos GL_EXT_shadow_funcs'
		'GL_EXT_stencil_wrap GL_ARB_vertex_program GL_EXT_texture_rectangle'
		'GL_ARB_fragment_program GL_EXT_stencil_two_side'
		'GL_ATI_separate_stencil GL_ARB_vertex_buffer_object'
		'GL_EXT_texture_lod_bias GL_ARB_occlusion_query GL_ARB_fragment_shader'
		'GL_ARB_shader_objects GL_ARB_shading_language_100'
		'GL_ARB_texture_non_power_of_two GL_ARB_vertex_shader'
		'GL_NV_texgen_reflection GL_ARB_point_sprite'
		'GL_ARB_fragment_program_shadow GL_EXT_blend_equation_separate'
		'GL_ARB_depth_texture GL_ARB_texture_rectangle GL_ARB_draw_buffers'
		'GL_ARB_color_buffer_float GL_ARB_half_float_pixel GL_ARB_texture_float'
		'GL_ARB_pixel_buffer_object GL_EXT_framebuffer_object'
		'GL_ARB_draw_instanced GL_ARB_half_float_vertex GL_ARB_occlusion_query2'
		'GL_EXT_draw_buffers2 GL_WIN_swap_hint GL_EXT_texture_sRGB'
		'GL_ARB_multisample GL_EXT_packed_float GL_EXT_texture_shared_exponent'
		'GL_ARB_texture_rg GL_ARB_texture_compression_rgtc'
		'GL_NV_conditional_render GL_EXT_texture_swizzle GL_ARB_sync'
		'GL_ARB_framebuffer_sRGB GL_EXT_packed_depth_stencil'
		'GL_ARB_depth_buffer_float GL_EXT_transform_feedback'
		'GL_EXT_framebuffer_blit GL_EXT_framebuffer_multisample'
		'GL_ARB_framebuffer_object GL_EXT_texture_array GL_EXT_texture_integer'
		'GL_ARB_map_buffer_range GL_EXT_texture_snorm'
		'GL_INTEL_performance_queries GL_ARB_copy_buffer GL_ARB_sampler_objects'
		'GL_NV_primitive_restart GL_ARB_seamless_cube_map'
		'GL_ARB_uniform_buffer_object GL_ARB_depth_clamp'
		'GL_ARB_vertex_array_bgra GL_ARB_shader_bit_encoding'
		'GL_ARB_draw_buffers_blend GL_ARB_texture_query_lod'
		'GL_ARB_explicit_attrib_location GL_ARB_draw_elements_base_vertex'
		'GL_ARB_instanced_arrays GL_ARB_fragment_coord_conventions'
		'GL_EXT_gpu_program_parameters GL_ARB_texture_buffer_object_rgb32'
		'GL_ARB_compatibility GL_ARB_texture_rgb10_a2ui'
		'GL_ARB_vertex_type_2_10_10_10_rev GL_ARB_timer_query'
		'GL_INTEL_map_texture GL_ARB_vertex_array_object'
		'GL_ARB_provoking_vertex '

Implementation Dependent OpenGL Limits:
============================================

Maximum Fixed Function Texture Units:	8

GLSL:
Maximum Varying Floats:	41
Maximum Vertex Attributes:	16
Maximum Vertex Uniform Components:	512
Maximum Fragment Uniform Components:	1024
Maximum Vertex Image Units:	16
Maximum Fragment Image Units:	16
Maximum Pipeline Image Units:	16

Thank you for your help.

David

Explanation is that when doing offscreen rendering or using depth of field, SSAO effect is rendered to an offscreen buffer first. In case of offscreen rendering this is just copied to a file after rendering. In the case of depth of field, the SSAO offscreen buffer is passed as input to the depth of field effect. Using an offscreen buffer as opposed to not using one is what triggers the driver bug.

Recent buildbot should be fixed for your card, if it's not, please ping me here.

Thanks!

Thank you Antony, really appreciate the information.

Tried a build after your commit, viewport is corrected, regrettably the patch breaks OpenGL render.

Blender 2.74.5 (Hash eb81153)
Viewport AO HD 3000 with fix

OpenGL render AO HD 3000 with fix

Based upon your helpful explanation, (just for problematic GPUs) instead of reversing GG.dfdyfactors[1] = 1.0; value, is it possible to move AO rendering to the offscreen buffer, so viewport and OpenGL AO render provide the expected outcome?

Hope your week is going well.

David

Can you try once more with the buildbot build tomorrow? I have an HD3000 in my laptop too but for some weird reason it's impossible to use optimus options to switch to Intel card. Probably some bug with recent drivers, and troubleshooting the issue gave poor results since I must be the only person in the multiverse wanting to use enforce the Intel card. Anyway, for that reason I can't really debug this locally. I tried changing the offscreen factor based on what you mentioned above, I just hope it's correct.

As to always rendering offscreen, yes it can be done, but it's an extra step. Why lose the performance if we can avoid it?

Certainly (see test images).

Which NVIDIA driver are you using, 347.88, 350.12, other? I'm presently using 347.88, but have downloaded 350.12 to try and see if I can reproduce your optimus issue.

Your "only person in the multiverse wanting to..." comment made me smile. Generally, I use the NVIDIA card for improved view-port display performance. If using the NVIDIA card for GPGPU, I start another instance of Blender using the HD 3000 for display, I'm then able to carry on modelling without slowdowns. Also, unless I switch to discrete NVIDIA GPU in the BIOS, I have Linux Mint (dual boot) setup to use the HD 3000 by default, this saves battery life plus overcomes some GNU/Linux NVIDIA driver issues. So you're not the only one using your HD 3000. :)

.

Regrettably GG.dfdyfactors[1] = -1.0; breaks offscreen buffer rendering and doesn't help OpenGL render.

Test images for Blender 2.74.5 (Hash 6c15f30)
View-port AO HD 3000

OpenGL render AO HD 3000

Test images including DoF, to check offscreen buffer rendering, Blender 2.74.5 (Hash 6c15f30)
View-port AO with DoF HD 3000

OpenGL render AO with DoF HD 3000

.

For problematic cards, it seems offscreen buffer rendering is the only solution (below images), even with a minor (based on the addition of DoF) performance hit?

Offscreen buffer rendering test, official Blender 2.74 (Hash 000dfc0)
View-port AO with DoF (distance 1000) HD 3000 without fix

OpenGL AO render with DoF (distance 1000) HD 3000 without fix

David

Alright, I have my Intel back after the last NVIDIA update. My driver is a little older but I'll try to patch up both versions if I can download the same version.

Alright, I think it should be fine now, thanks for the report!

As you suspect, everything appears to be fine. Your work on fixing this is very much appreciated, thank you!

In connection with [150a4b2], unless new problematic hardware versions are discovered, rather needing to keep adding drivers to the list, would it be reasonable to explain to users there is a fix in place, they just need to update to the latest available Intel driver for their hardware (and possibly supply a link to the Intel driver page)?

We'd have to keep the list anyway to detect if a driver is problematic. In that case, we can just patch it blender side.

Thanks for your quick reply. I meant rather than several driver revisions for the same hardware, the list will contain just the most recent driver revision for each piece of troublesome hardware. Then ask people to upgrade to the latest driver...

Considering other future viewport improvements, hoped the above idea would be less work for you, and people would not need to wait for the next official/Buildbot version of Blender to be patched, as far as they are concerned (after updating their GPU driver) the fix would be transparent. In effect anyone with a HD 4000 (or above) will gain the benefit of Intel's patched driver, anyone with a HD 3000 (or other reported hardware) would gain the benefit of your Blender patch, plus most recent driver improvements.

The problem is that driver version/vendor/hardware strings do not have a standard format according to OpenGL spec. They can change at any time.
So the sentence "most recent driver" does not make sense. It would make sense if you could establish a robust way of comparison operation between driver strings, which is not the case here.

Based upon Micheal Coppock (Intel) last reply, I assumed driver 9.17.10.4101 will be the last revision for the HD 3000 line, as it has reached end of life, with HD 4000 soon to follow. Shame Intel would not release one last diver to fix their bug in the HD 3000 GPU, but understand products cannot be supported (on Windows) forever. With understand exceptions, this is also another benefit of GNU/Linux.

Not really keen on Windows 10, but may try it bare metal to see how Microsoft's Intel driver compares.

Anyway, concerned taking too much of your time, thank you for an interesting discussion and taking time to explain complexities, will leave you to code in peace. :)