Transparent screenshots for one output

[haansn08]

My left output refuses to get screenshotted by grim:

As you can see the right output works fine :)

stderr of grim with `WAYLAND_DEBUG=client`

[531637.416]  -> [email protected]_registry(new id wl_registry@2)
[531637.831] [email protected](1, "wl_shm", 1)
[531637.890]  -> [email protected](1, "wl_shm", 1, new id [unknown]@3)
[531637.937] [email protected](2, "wl_drm", 2)
[531637.965] [email protected](3, "zwp_linux_dmabuf_v1", 3)
[531637.993] [email protected](4, "wl_compositor", 4)
[531638.020] [email protected](5, "wl_subcompositor", 1)
[531638.046] [email protected](6, "wl_data_device_manager", 3)
[531638.073] [email protected](7, "zwlr_gamma_control_manager_v1", 1)
[531638.100] [email protected](8, "gtk_primary_selection_device_manager", 1)
[531638.127] [email protected](9, "zxdg_output_manager_v1", 3)
[531638.156]  -> [email protected](9, "zxdg_output_manager_v1", 2, new id [unknown]@4)
[531638.198] [email protected](10, "org_kde_kwin_idle", 1)
[531638.226] [email protected](11, "zwp_idle_inhibit_manager_v1", 1)
[531638.253] [email protected](12, "zwlr_layer_shell_v1", 2)
[531638.279] [email protected](13, "xdg_wm_base", 2)
[531638.307] [email protected](14, "zwp_tablet_manager_v2", 1)
[531638.334] [email protected](15, "org_kde_kwin_server_decoration_manager", 1)
[531638.361] [email protected](16, "zxdg_decoration_manager_v1", 1)
[531638.388] [email protected](17, "zwp_relative_pointer_manager_v1", 1)
[531638.414] [email protected](18, "zwp_pointer_constraints_v1", 1)
[531638.441] [email protected](19, "wp_presentation", 1)
[531638.468] [email protected](20, "zwlr_output_manager_v1", 1)
[531638.495] [email protected](21, "zwlr_output_power_manager_v1", 1)
[531638.522] [email protected](22, "zwp_input_method_manager_v2", 1)
[531638.549] [email protected](23, "zwp_text_input_manager_v3", 1)
[531638.576] [email protected](24, "zwlr_foreign_toplevel_manager_v1", 2)
[531638.603] [email protected](25, "zwlr_export_dmabuf_manager_v1", 1)
[531638.630] [email protected](26, "zwlr_screencopy_manager_v1", 3)
[531638.657]  -> [email protected](26, "zwlr_screencopy_manager_v1", 1, new id [unknown]@5)
[531638.705] [email protected](27, "zwlr_data_control_manager_v1", 2)
[531638.725] [email protected](28, "zwp_primary_selection_device_manager_v1", 1)
[531638.746] [email protected](29, "wp_viewporter", 1)
[531638.766] [email protected](30, "zwp_virtual_keyboard_manager_v1", 1)
[531638.786] [email protected](31, "zwlr_virtual_pointer_manager_v1", 2)
[531638.806] [email protected](32, "zwlr_input_inhibit_manager_v1", 1)
[531638.826] [email protected](33, "zwp_keyboard_shortcuts_inhibit_manager_v1", 1)
[531638.846] [email protected](34, "wl_seat", 7)
[531638.867] [email protected](35, "zwp_pointer_gestures_v1", 1)
[531638.887] [email protected](36, "wl_output", 3)
[531638.908]  -> [email protected](36, "wl_output", 3, new id [unknown]@6)
[531638.936] [email protected](37, "wl_output", 3)
[531638.956]  -> [email protected](37, "wl_output", 3, new id [unknown]@7)
[531638.986]  -> [email protected](new id wl_callback@8)
[531639.149] [email protected]_id(8)
[531639.174] [email protected](0, 0, 480, 270, 0, "Samsung Electric Company", "S22B300", 0)
[531639.222] [email protected](1, 1920, 1080, 60000)
[531639.249] [email protected](1)
[531639.259] [email protected]()
[531639.267] [email protected](0, 0, 520, 300, 0, "Unknown", "Q24", 0)
[531639.313] [email protected](1, 1600, 1200, 60000)
[531639.339] [email protected](1)
[531639.349] [email protected]()
[531639.356] [email protected](10760)
[531639.368]  -> [email protected]_xdg_output(new id zxdg_output_v1@8, wl_output@7)
[531639.388]  -> [email protected]_xdg_output(new id zxdg_output_v1@9, wl_output@6)
[531639.524] [email protected]("VGA-1")
[531639.547] [email protected]("Unknown Q24 709050660001 (VGA-1)")
[531639.559] [email protected]_position(0, 0)
[531639.575] [email protected]_size(1600, 1200)
[531639.590] [email protected]()
[531639.598] [email protected]()
[531639.605] [email protected]("DVI-I-1")
[531639.615] [email protected]("Samsung Electric Company S22B300 H4XC602789 (DVI-I-1)")
[531639.633] [email protected]_position(1600, 50)
[531639.649] [email protected]_size(1920, 1080)
[531639.664] [email protected]()
[531639.671] [email protected]()
[531639.680]  -> [email protected](new id wl_callback@10)
[531639.798] [email protected]_id(10)
[531639.821] [email protected](10760)
[531639.835]  -> [email protected]_output(new id zwlr_screencopy_frame_v1@10, 0, wl_output@7)
[531639.861]  -> [email protected]_output(new id zwlr_screencopy_frame_v1@11, 0, wl_output@6)
[531640.066] [email protected](0, 1600, 1200, 6400)
[531640.158]  -> [email protected]_pool(new id wl_shm_pool@12, fd 5, 7680000)
[531640.185]  -> [email protected]_buffer(new id wl_buffer@13, 0, 1600, 1200, 6400, 0)
[531640.223]  -> [email protected]()
[531640.232]  -> [email protected](wl_buffer@13)
[531640.243] [email protected](0, 1920, 1080, 7680)
[531640.283]  -> [email protected]_pool(new id wl_shm_pool@14, fd 6, 8294400)
[531640.307]  -> [email protected]_buffer(new id wl_buffer@15, 0, 1920, 1080, 7680, 0)
[531640.344]  -> [email protected]()
[531640.352]  -> [email protected](wl_buffer@15)
[531661.715] [email protected]_id(12)
[531661.739] [email protected]_id(14)
[531661.754] [email protected](1)
[531661.759] [email protected](0, 5547, 292587586)
[531674.420] [email protected](1)
[531674.443] [email protected](0, 5547, 311122860)
[531892.771]  -> [email protected]()
[531892.945]  -> [email protected]()
[531892.951]  -> [email protected]()
[531892.955]  -> [email protected]()
[531892.958]  -> [email protected]()
[531893.151]  -> [email protected]()
[531893.155]  -> [email protected]()
[531893.158]  -> [email protected]()
[531893.162]  -> [email protected]()
[531893.165]  -> [email protected]()

output of `swaymsg -pt get_outputs`

Output DVI-I-1 'Samsung Electric Company S22B300 H4XC602789' (focused)
  Current mode: 1920x1080 @ 60.000000 Hz
  Position: 1600,50
  Scale factor: 1.000000
  Scale filter: nearest
  Subpixel hinting: unknown
  Transform: normal
  Workspace: 2
  Max render time: off
  Adaptive sync: disabled
  Available modes:
    720x400 @ 70.082001 Hz
    640x480 @ 59.939999 Hz
    640x480 @ 66.667000 Hz
    640x480 @ 72.808998 Hz
    640x480 @ 75.000000 Hz
    800x600 @ 56.250000 Hz
    800x600 @ 60.317001 Hz
    800x600 @ 72.188004 Hz
    800x600 @ 75.000000 Hz
    832x624 @ 74.551003 Hz
    1024x768 @ 60.004002 Hz
    1024x768 @ 70.069000 Hz
    1024x768 @ 75.028999 Hz
    1280x720 @ 60.000000 Hz
    1152x864 @ 75.000000 Hz
    1280x800 @ 59.810001 Hz
    1440x900 @ 59.887001 Hz
    1280x1024 @ 60.020000 Hz
    1280x1024 @ 75.025002 Hz
    1600x900 @ 60.000000 Hz
    1680x1050 @ 59.953999 Hz
    1920x1080 @ 60.000000 Hz

Output VGA-1 'Unknown Q24 709050660001'
  Current mode: 1600x1200 @ 60.000000 Hz
  Position: 0,0
  Scale factor: 1.000000
  Scale filter: nearest
  Subpixel hinting: unknown
  Transform: normal
  Workspace: 1
  Max render time: off
  Adaptive sync: disabled
  Available modes:
    720x400 @ 70.082001 Hz
    640x480 @ 59.939999 Hz
    640x480 @ 66.667000 Hz
    640x480 @ 72.808998 Hz
    640x480 @ 75.000000 Hz
    800x600 @ 56.250000 Hz
    800x600 @ 60.317001 Hz
    800x600 @ 72.188004 Hz
    800x600 @ 75.000000 Hz
    832x624 @ 74.551003 Hz
    1024x768 @ 60.004002 Hz
    1024x768 @ 70.069000 Hz
    1024x768 @ 75.028999 Hz
    1152x864 @ 75.000000 Hz
    1280x960 @ 60.000000 Hz
    1440x900 @ 59.887001 Hz
    1440x900 @ 74.984001 Hz
    1280x1024 @ 60.020000 Hz
    1280x1024 @ 75.025002 Hz
    1400x1050 @ 59.978001 Hz
    1680x1050 @ 59.953999 Hz
    1600x1200 @ 60.000000 Hz

Version 1.3.1-1 on manjaro.

[emersion]

Hmm, weird. Does it work fine to capture only VGA-1?

[haansn08]

Running grim -o "VGA-1" gives a completely transparent png image.
I just noticed everything works fine when setting the output format to jpeg or ppm.

[emersion]

Ah, these don't support alpha. Maybe we're incorrectly setting the alpha channel or something?

[emersion]

Ref #17