Flashing Horizontal Red Line Artefact When Rendering 2D Game With OpenGL on Intel UHD Graphics

[TommiGustafsson]

Setup

We have a multiplatform 2D game using the following technologies:

• .NET MAUI 9.0 Preview 5
• . NET SDK 9.0 Preview 5
• WinUI 3
• WinAppSDK 1.5.x
• C#/WinRT v2.0.4.44221
• SkiaSharp 3.0 Preview3.1
• Skia v115 with Ganesh backend
• OpenGL (libEGL.dll, whatever version that is)

I'm testing the game on Windows, using the following hardware and software:

• Asus ProArt Studiobook Laptop
• Windows 11 Pro 64-bit 23H2 22631.381
• Windows Feature Experience Pack 1000.22700.1020.0
• 13th Gen Intel(R) Core(TM) i9-13980HX
• Intel UHD Graphics (Integrated GPU) with 31.0.101.5593 drivers (also tested with 31.0.101.5592 drivers)
• NVIDIA Geforce RTX 4060 Laptop 8GB (Dedicated GPU) with 555.99 drivers
• 32 GB RAM
• 3200x2000 display with 200% scaling (I did try also 150% scaling)

Problem

On Windows, when we use OpenGL for rendering, on Intel UHD Graphics, there is a flashing thin horizontal red line artefact appearing.

There's a video about the problem here:

https://github.com/mono/SkiaSharp/issues/2913

The line is thin, wherefore you need to maximize the video to see it. The line usually appears when the character is moving north or south.

The red line artefact does not appear when using the NVIDIA GPU, so it appears to be an Intel GPU problem.

Any ideas how to solve this issue on Intel UHD GPU?

[Arturo_Intel]

Hello @TommiGustafsson :

Welcome to the forum.

Is there a way to share a copy of the game to do some tests on my lab? I want to check if it is also happening with the latest Intel's GPUs.

If not, are you able to create a homebrew code that replicates the issue?

--r2

[TommiGustafsson · Accepted solution]

Sorry being late to answer this, but I was investigating the problem. It's now fixed. We had to increase the size of the target rectangle by 1 pixel, when we were rendering graphics from our sprite sheet. This seemed to fix the red line. It's a bit of a hack, but it works.

[Arturo_Intel]

@TommiGustafsson Glad to read that.

If you or your team have any questions or new issues, do not hesitate to reach out!

Thanks

-- r2