examples/skipdraw: wrong rendering result with SetScreenClearedEveryFrame(false)

[hajimehoshi]

Ebitengine Version

Both v2.6.7 and v2.7.0

Operating System

• Windows
• macOS
• Linux
• FreeBSD
• OpenBSD
• Android
• iOS
• Nintendo Switch
• PlayStation 5
• Xbox
• Web Browsers

Go Version (go version)

go version go1.22.0 linux/arm64

What steps will reproduce the problem?

Run github.com/crgimenes/neko commit: eb5fed9b4f321d7914da25d03e88c0710d423c02

What is the expected result?

The rendering result is correct

neko.mp4

What happens instead?

The rendering result is not correct

Anything else you feel useful to add?

This issue is forked from #2951

After removing SetScreenClearedEveryFrame(false) and fixing the code to always render the sprite, the issue was fixed.

[hajimehoshi]

This could be reproduced with examples/skipdraw.

skipdraw.mp4

[hajimehoshi]

This doesn't seem a fixable issue as vsync doesn't work in my environment

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 $$P      d$'     ,    $$P    Packages: 1905 (dpkg) 
 $$:      $$.   -    ,d$$'    Shell: bash 5.2.15 
 $$;      Y$b._   _,d$P'      Resolution: 1800x1126 
 Y$$.    `.`"Y$$$$P"'         DE: Cinnamon 5.6.8 
 `$$b      "-.__              WM: Mutter (Muffin) 
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   `Y$$.                      Theme: Adwaita [GTK2/3] 
     `$$b.                    Icons: gnome [GTK2/3] 
       `Y$$b.                 Terminal: gnome-terminal 
          `"Y$b._             CPU: (2) 
              `"""            GPU: 00:0a.0 Red Hat, Inc. Virtio 1.0 GPU 
                              Memory: 1081MiB / 1978MiB 

[SolsticeSpectrum]

@hajimehoshi If you send me the example skipdraw code, I can test it on my machine. Idk if that would help in any way.

[hajimehoshi]

Thanks. I need to test this with a proper Linux machine rather than a Parallels VM first.