Double render on alternating redraws while scrolling

[xpollen8]

0.2.0

(Using local data), scrolling down the page exhibits a "double draw" condition, whether via scrollwheel or dragging the elevator. Let me know if you need the html file to reproduce.

[xpollen8]

Here's a test case

shrink your browsers to force scrollbars

[xpollen8]

Ah. It isn't just my data. Here is the Dat page linked-to from Beaker's "home page".
OSX 10.10.5

[pfrazee]

Does that anomaly only occur during the scrolling, or does it persist on the page when it's not moving?

[xpollen8]

Yes, it remains visibly doubled until something forces a redraw event.

[pfrazee]

This is probably an Electron/Chrome issue. I'm searching for other reports that match it. electron/electron#6666 may be related.

[pfrazee]

Could you create a dump of chrome://gpu/ for me?

[pfrazee]

electron/electron#3611 may also be related

[xpollen8]

Graphics Feature Status
Canvas: Hardware accelerated
Flash: Hardware accelerated
Flash Stage3D: Hardware accelerated
Flash Stage3D Baseline profile: Hardware accelerated
Compositing: Hardware accelerated
Multiple Raster Threads: Enabled
Native GpuMemoryBuffers: Hardware accelerated
Rasterization: Software only. Hardware acceleration disabled
Video Decode: Hardware accelerated
Video Encode: Hardware accelerated
WebGL: Hardware accelerated
Driver Bug Workarounds
disable_multimonitor_multisampling
disable_overlay_ca_layers
disable_texture_cube_map_seamless
disable_webgl_rgb_multisampling_usage
init_varyings_without_static_use
msaa_is_slow
pack_parameters_workaround_with_pack_buffer
regenerate_struct_names
scalarize_vec_and_mat_constructor_args
set_zero_level_before_generating_mipmap
unfold_short_circuit_as_ternary_operation
unpack_alignment_workaround_with_unpack_buffer
use_intermediary_for_copy_texture_image
validate_multisample_buffer_allocation
Problems Detected
Multisampling is buggy on OSX when multiple monitors are connected: 237931
Applied Workarounds: disable_multimonitor_multisampling
Multisampled renderbuffer allocation must be validated on some Macs: 290391
Applied Workarounds: validate_multisample_buffer_allocation
Unfold short circuit on Mac OS X: 307751
Applied Workarounds: unfold_short_circuit_as_ternary_operation
Mac drivers handle varyings without static use incorrectly: 322760
Applied Workarounds: init_varyings_without_static_use
Always rewrite vec/mat constructors to be consistent: 398694
Applied Workarounds: scalarize_vec_and_mat_constructor_args
Mac drivers handle struct scopes incorrectly: 403957
Applied Workarounds: regenerate_struct_names
On Intel GPUs MSAA performance is not acceptable for GPU rasterization: 527565
Applied Workarounds: msaa_is_slow
glGenerateMipmap fails if the zero texture level is not set on some Mac drivers: 560499
Applied Workarounds: set_zero_level_before_generating_mipmap
Pack parameters work incorrectly with pack buffer bound: 563714
Applied Workarounds: pack_parameters_workaround_with_pack_buffer
Alignment works incorrectly with unpack buffer bound: 563714
Applied Workarounds: unpack_alignment_workaround_with_unpack_buffer
copyTexImage2D fails when reading from IOSurface on multiple GPU types.: 581777
Applied Workarounds: use_intermediary_for_copy_texture_image
Seamless cubemap does not work for Mac Intel: 597794
Applied Workarounds: disable_texture_cube_map_seamless
IOSurface use becomes pathologically slow over time on 10.10.: 580616
Applied Workarounds: disable_overlay_ca_layers
Multisample renderbuffers with format GL_RGB8 have performance issues on Intel GPUs.: 607130
Applied Workarounds: disable_webgl_rgb_multisampling_usage
Accelerated rasterization has been disabled, either via blacklist, about:flags or the command line.
Disabled Features: rasterization
Version Information
Data exported 8/23/2016, 5:15:16 PM
Chrome version Chrome/52.0.2743.82
Operating system Mac OS X 10.10.5
Software rendering list version 11.7
Driver bug list version 8.68
ANGLE commit id unknown hash
2D graphics backend Skia
Command Line Args Browser.app/Contents/MacOS/Beaker Browser --no-sandbox --allow-file-access-from-files --enable-avfoundation --standard-schemes=dat,view-dat
Driver Information
Initialization time 160
In-process GPU false
Sandboxed false
GPU0 VENDOR = 0x8086, DEVICE= 0x162b ACTIVE
Optimus false
AMD switchable false
Driver vendor
Driver version 10.6.33
Driver date
Pixel shader version 1.20
Vertex shader version 1.20
Max. MSAA samples 8
Machine model name MacBookPro
Machine model version 12.1
GL_VENDOR Intel
GL_RENDERER Intel(R) Iris(TM) Graphics 6100
GL_VERSION 2.1 INTEL-10.6.33
GL_EXTENSIONS GL_ARB_color_buffer_float GL_ARB_depth_buffer_float GL_ARB_depth_clamp GL_ARB_depth_texture GL_ARB_draw_buffers GL_ARB_draw_elements_base_vertex GL_ARB_draw_instanced GL_ARB_fragment_program GL_ARB_fragment_program_shadow GL_ARB_fragment_shader GL_ARB_framebuffer_object GL_ARB_framebuffer_sRGB GL_ARB_half_float_pixel GL_ARB_half_float_vertex GL_ARB_instanced_arrays 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_seamless_cube_map GL_ARB_shader_objects GL_ARB_shader_texture_lod GL_ARB_shading_language_100 GL_ARB_shadow GL_ARB_sync GL_ARB_texture_border_clamp 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_non_power_of_two GL_ARB_texture_rectangle GL_ARB_texture_rg GL_ARB_transpose_matrix GL_ARB_vertex_array_bgra GL_ARB_vertex_blend 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_minmax GL_EXT_blend_subtract GL_EXT_clip_volume_hint GL_EXT_debug_label GL_EXT_debug_marker GL_EXT_draw_buffers2 GL_EXT_draw_range_elements GL_EXT_fog_coord GL_EXT_framebuffer_blit GL_EXT_framebuffer_multisample GL_EXT_framebuffer_multisample_blit_scaled GL_EXT_framebuffer_object GL_EXT_framebuffer_sRGB GL_EXT_geometry_shader4 GL_EXT_gpu_program_parameters GL_EXT_gpu_shader4 GL_EXT_multi_draw_arrays GL_EXT_packed_depth_stencil GL_EXT_packed_float GL_EXT_provoking_vertex GL_EXT_rescale_normal GL_EXT_secondary_color GL_EXT_separate_specular_color GL_EXT_shadow_funcs GL_EXT_stencil_two_side GL_EXT_stencil_wrap GL_EXT_texture_array GL_EXT_texture_compression_dxt1 GL_EXT_texture_compression_s3tc GL_EXT_texture_env_add GL_EXT_texture_filter_anisotropic GL_EXT_texture_integer GL_EXT_texture_lod_bias GL_EXT_texture_rectangle GL_EXT_texture_shared_exponent GL_EXT_texture_sRGB GL_EXT_texture_sRGB_decode GL_EXT_timer_query GL_EXT_transform_feedback GL_EXT_vertex_array_bgra GL_APPLE_aux_depth_stencil GL_APPLE_client_storage GL_APPLE_element_array GL_APPLE_fence GL_APPLE_float_pixels GL_APPLE_flush_buffer_range GL_APPLE_flush_render GL_APPLE_object_purgeable GL_APPLE_packed_pixels GL_APPLE_pixel_buffer GL_APPLE_rgb_422 GL_APPLE_row_bytes GL_APPLE_specular_vector GL_APPLE_texture_range GL_APPLE_transform_hint GL_APPLE_vertex_array_object GL_APPLE_vertex_array_range GL_APPLE_vertex_point_size GL_APPLE_vertex_program_evaluators GL_APPLE_ycbcr_422 GL_ATI_separate_stencil GL_ATI_texture_env_combine3 GL_ATI_texture_float GL_ATI_texture_mirror_once GL_IBM_rasterpos_clip GL_NV_blend_square GL_NV_conditional_render GL_NV_depth_clamp GL_NV_fog_distance GL_NV_light_max_exponent GL_NV_texgen_reflection GL_NV_texture_barrier GL_SGIS_generate_mipmap GL_SGIS_texture_edge_clamp GL_SGIS_texture_lod
Disabled Extensions
Window system binding vendor
Window system binding version
Window system binding extensions
Direct rendering Yes
Reset notification strategy 0x0000
GPU process crash count 0
Compositor Information
Tile Update Mode Zero-copy
Partial Raster Disabled
GpuMemoryBuffers Status
ATC Software only
ATCIA Software only
DXT1 Software only
DXT5 Software only
ETC1 Software only
R_8 GPU_READ_CPU_READ_WRITE, GPU_READ_CPU_READ_WRITE_PERSISTENT
BGR_565 Software only
RGBA_4444 Software only
RGBX_8888 Software only
RGBA_8888 GPU_READ, SCANOUT
BGRX_8888 GPU_READ, SCANOUT
BGRA_8888 GPU_READ, SCANOUT, GPU_READ_CPU_READ_WRITE, GPU_READ_CPU_READ_WRITE_PERSISTENT
YUV_420 Software only
YUV_420_BIPLANAR GPU_READ_CPU_READ_WRITE, GPU_READ_CPU_READ_WRITE_PERSISTENT
UYVY_422 GPU_READ_CPU_READ_WRITE, GPU_READ_CPU_READ_WRITE_PERSISTENT

[pfrazee]

Ok, I'm going to file with Electron to see what they have to say.

[pfrazee]

electron/electron#6950. Thanks for filing, I'll keep you up to date.

[pfrazee]

Ive just begun to experience this, on a site that has a canvas element.
Funny that I never saw it before then.

On Tue, Aug 23, 2016 at 7:16 PM, xpollen8 notifications@github.com wrote:

Graphics Feature Status
Canvas: Hardware accelerated
Flash: Hardware accelerated
Flash Stage3D: Hardware accelerated
Flash Stage3D Baseline profile: Hardware accelerated
Compositing: Hardware accelerated
Multiple Raster Threads: Enabled
Native GpuMemoryBuffers: Hardware accelerated
Rasterization: Software only. Hardware acceleration disabled
Video Decode: Hardware accelerated
Video Encode: Hardware accelerated
WebGL: Hardware accelerated
Driver Bug Workarounds
disable_multimonitor_multisampling
disable_overlay_ca_layers
disable_texture_cube_map_seamless
disable_webgl_rgb_multisampling_usage
init_varyings_without_static_use
msaa_is_slow
pack_parameters_workaround_with_pack_buffer
regenerate_struct_names
scalarize_vec_and_mat_constructor_args
set_zero_level_before_generating_mipmap
unfold_short_circuit_as_ternary_operation
unpack_alignment_workaround_with_unpack_buffer
use_intermediary_for_copy_texture_image
validate_multisample_buffer_allocation
Problems Detected
Multisampling is buggy on OSX when multiple monitors are connected: 237931
Applied Workarounds: disable_multimonitor_multisampling
Multisampled renderbuffer allocation must be validated on some Macs: 290391
Applied Workarounds: validate_multisample_buffer_allocation
Unfold short circuit on Mac OS X: 307751
Applied Workarounds: unfold_short_circuit_as_ternary_operation
Mac drivers handle varyings without static use incorrectly: 322760
Applied Workarounds: init_varyings_without_static_use
Always rewrite vec/mat constructors to be consistent: 398694
Applied Workarounds: scalarize_vec_and_mat_constructor_args
Mac drivers handle struct scopes incorrectly: 403957
Applied Workarounds: regenerate_struct_names
On Intel GPUs MSAA performance is not acceptable for GPU rasterization:
527565
Applied Workarounds: msaa_is_slow
glGenerateMipmap fails if the zero texture level is not set on some Mac
drivers: 560499
Applied Workarounds: set_zero_level_before_generating_mipmap
Pack parameters work incorrectly with pack buffer bound: 563714
Applied Workarounds: pack_parameters_workaround_with_pack_buffer
Alignment works incorrectly with unpack buffer bound: 563714
Applied Workarounds: unpack_alignment_workaround_with_unpack_buffer
copyTexImage2D fails when reading from IOSurface on multiple GPU types.:
581777
Applied Workarounds: use_intermediary_for_copy_texture_image
Seamless cubemap does not work for Mac Intel: 597794
Applied Workarounds: disable_texture_cube_map_seamless
IOSurface use becomes pathologically slow over time on 10.10.: 580616
Applied Workarounds: disable_overlay_ca_layers
Multisample renderbuffers with format GL_RGB8 have performance issues on
Intel GPUs.: 607130
Applied Workarounds: disable_webgl_rgb_multisampling_usage
Accelerated rasterization has been disabled, either via blacklist,
about:flags or the command line.
Disabled Features: rasterization
Version Information
Data exported 8/23/2016, 5:15:16 PM
Chrome version Chrome/52.0.2743.82
Operating system Mac OS X 10.10.5
Software rendering list version 11.7
Driver bug list version 8.68
ANGLE commit id unknown hash
2D graphics backend Skia
Command Line Args Browser.app/Contents/MacOS/Beaker Browser --no-sandbox
--allow-file-access-from-files --enable-avfoundation
--standard-schemes=dat,view-dat
Driver Information
Initialization time 160
In-process GPU false
Sandboxed false
GPU0 VENDOR = 0x8086, DEVICE= 0x162b ACTIVE
Optimus false
AMD switchable false
Driver vendor

Driver version 10.6.33
Driver date
Pixel shader version 1.20
Vertex shader version 1.20
Max. MSAA samples 8
Machine model name MacBookPro
Machine model version 12.1
GL_VENDOR Intel
GL_RENDERER Intel(R) Iris(TM) Graphics 6100
GL_VERSION 2.1 INTEL-10.6.33
GL_EXTENSIONS GL_ARB_color_buffer_float GL_ARB_depth_buffer_float
GL_ARB_depth_clamp GL_ARB_depth_texture GL_ARB_draw_buffers
GL_ARB_draw_elements_base_vertex GL_ARB_draw_instanced
GL_ARB_fragment_program GL_ARB_fragment_program_shadow
GL_ARB_fragment_shader GL_ARB_framebuffer_object GL_ARB_framebuffer_sRGB
GL_ARB_half_float_pixel GL_ARB_half_float_vertex GL_ARB_instanced_arrays
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_seamless_cube_map GL_ARB_shader_objects
GL_ARB_shader_texture_lod GL_ARB_shading_language_100 GL_ARB_shadow
GL_ARB_sync GL_ARB_texture_border_clamp 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_non_power_of_two
GL_ARB_texture_rectangle GL_ARB_texture_rg GL_ARB_transpose_matrix
GL_ARB_vertex_array_bgra GL_ARB_vertex_blend 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_minmax GL_EXT_blend_subtract
GL_EXT_clip_volume_hint GL_EXT_debug_label GL_EXT_debug_marker
GL_EXT_draw_buffers2 GL_EXT_draw_range_elements GL_EXT_fog_coord
GL_EXT_framebuffer_blit GL_EXT_framebuffer_multisample GL_EXT_framebuffer_multisample_blit_scaled
GL_EXT_framebuffer_object GL_EXT_framebuffer_sRGB GL_EXT_geometry_shader4
GL_EXT_gpu_program_parameters GL_EXT_gpu_shader4 GL_EXT_multi_draw_arrays
GL_EXT_packed_depth_stencil GL_EXT_packed_float GL_EXT_provoking_vertex
GL_EXT_rescale_normal GL_EXT_secondary_color GL_EXT_separate_specular_color
GL_EXT_shadow_funcs GL_EXT_stencil_two_side GL_EXT_stencil_wrap
GL_EXT_texture_array GL_EXT_texture_compression_dxt1
GL_EXT_texture_compression_s3tc GL_EXT_texture_env_add
GL_EXT_texture_filter_anisotropic GL_EXT_texture_integer
GL_EXT_texture_lod_bias GL_EXT_texture_rectangle
GL_EXT_texture_shared_exponent GL_EXT_texture_sRGB
GL_EXT_texture_sRGB_decode GL_EXT_timer_query GL_EXT_transform_feedback
GL_EXT_vertex_array_bgra GL_APPLE_aux_depth_stencil GL_APPLE_client_storage
GL_APPLE_element_array GL_APPLE_fence GL_APPLE_float_pixels
GL_APPLE_flush_buffer_range GL_APPLE_flush_render GL_APPLE_object_purgeable
GL_APPLE_packed_pixels GL_APPLE_pixel_buffer GL_APPLE_rgb_422
GL_APPLE_row_bytes GL_APPLE_specular_vector GL_APPLE_texture_range
GL_APPLE_transform_hint GL_APPLE_vertex_array_object
GL_APPLE_vertex_array_range GL_APPLE_vertex_point_size
GL_APPLE_vertex_program_evaluators GL_APPLE_ycbcr_422
GL_ATI_separate_stencil GL_ATI_texture_env_combine3 GL_ATI_texture_float
GL_ATI_texture_mirror_once GL_IBM_rasterpos_clip GL_NV_blend_square
GL_NV_conditional_render GL_NV_depth_clamp GL_NV_fog_distance
GL_NV_light_max_exponent GL_NV_texgen_reflection GL_NV_texture_barrier
GL_SGIS_generate_mipmap GL_SGIS_texture_edge_clamp GL_SGIS_texture_lod
Disabled Extensions
Window system binding vendor

Window system binding version

Window system binding extensions

Direct rendering Yes
Reset notification strategy 0x0000
GPU process crash count 0
Compositor Information
Tile Update Mode Zero-copy
Partial Raster Disabled
GpuMemoryBuffers Status
ATC Software only
ATCIA Software only
DXT1 Software only
DXT5 Software only
ETC1 Software only
R_8 GPU_READ_CPU_READ_WRITE, GPU_READ_CPU_READ_WRITE_PERSISTENT
BGR_565 Software only
RGBA_4444 Software only
RGBX_8888 Software only
RGBA_8888 GPU_READ, SCANOUT
BGRX_8888 GPU_READ, SCANOUT
BGRA_8888 GPU_READ, SCANOUT, GPU_READ_CPU_READ_WRITE,
GPU_READ_CPU_READ_WRITE_PERSISTENT
YUV_420 Software only
YUV_420_BIPLANAR GPU_READ_CPU_READ_WRITE, GPU_READ_CPU_READ_WRITE_
PERSISTENT
UYVY_422 GPU_READ_CPU_READ_WRITE, GPU_READ_CPU_READ_WRITE_PERSISTENT

—
You are receiving this because you commented.
Reply to this email directly, view it on GitHub
#68 (comment), or mute
the thread
https://github.com/notifications/unsubscribe-auth/ABNhU3GeKucC1xOSESl82WNEqp73Qdikks5qi41FgaJpZM4JrdJi
.

[pfrazee]

The Electron team punted this to Chromium. I'll see if there are some GPU modes that can be toggled, to fix this situation.

[xpollen8]

For what it's worth, the Brave browser doesn't exhibit the bug. Maybe there's an explicit fix they made..?

[pfrazee]

That's a good tip

[pfrazee]

Was able to reproduce this on another user's computer, and discovered that this only occurs on websites that don't set a background color explicitly (expecting the default white). That suggests that chromium the webview is not clearing the background buffer; the ghosting is the result of previous renders.