OpenGL selection line aliases to dashes on some monitors

[John Beard]

* Be in OpenGL GAL mode
* Start a polygon or zone
* After the first two points, the "leader" lines are dashed but the size of the dash varies as the line angle changes. Sometimes, usually at 90 degree points, it's solid and sometimes it's totally invisible.

I think the dashes here should be a constant length (in pixels), so, invariant whatever the angle and zoom.

Application: pcbnew
Version: (6.0.0-rc1-dev-242-ge556cb8c9), debug build
Libraries:
    wxWidgets 3.0.4
    libcurl/7.60.0 OpenSSL/1.1.0h zlib/1.2.11 libidn2/2.0.5 libpsl/0.20.2 (+libidn2/2.0.4) nghttp2/1.31.1
Platform: Linux 4.17.2-1-ARCH x86_64, 64 bit, Little endian, wxGTK
Build Info:
    wxWidgets: 3.0.4 (wchar_t,wx containers,compatible with 2.8) GTK+ 2.24
    Boost: 1.67.0
    OpenCASCADE Community Edition: 6.9.1
    Curl: 7.60.0
    Compiler: GCC 8.1.1 with C++ ABI 1012

Build settings:
    USE_WX_GRAPHICS_CONTEXT=OFF
    USE_WX_OVERLAY=OFF
    KICAD_SCRIPTING=ON
    KICAD_SCRIPTING_MODULES=ON
    KICAD_SCRIPTING_WXPYTHON=ON
    KICAD_SCRIPTING_ACTION_MENU=ON
    BUILD_GITHUB_PLUGIN=ON
    KICAD_USE_OCE=ON
    KICAD_USE_OCC=OFF
    KICAD_SPICE=ON

[Seth Hillbrand (sethh)]

Does this happen with all display settings in accelerated? No anti-aliasing/super-sample, etc?

I think that the line is meant to be solid.

[John Beard (john-j-beard)]

That would explain why I couldn't find how that dash length was set!

When I set 4x Antialiasling, it looks almost solid, but you can see some alternating opacities, which I suppose look more like dashes in other modes.

[Seth Hillbrand (sethh)]

I suspect that this is more pronounced on lower dpi monitors so I'm hesitant to adjust anything to compensate for it. I think maybe we can lump it in with selection customization options when we implement so that users can increase linewidth on their own along with color settings.

[Jeff Young (jeyjey)]

Is this still the case with the new OpenGL renderers? Or were those specific to eeschema?

[KiCad Janitor (kicad-janitor)]

KiCad bug tracker has moved to Gitlab. This report is now available here: https://gitlab.com/kicad/code/kicad/-/issues/2195