[media_kit v1.1.10] Access violations when multiple Flutter apps are running media_kit concurrently

[isaacy13]

Howdy,

I'm getting null access violations whenever multiple Flutter apps are running media_kit at the same time

media_kit: 1.1.10 media_kit_video: 1.2.4 media_kit_libs_video: 1.0.4

Steps taken so far:

• Enabled debug for Player configuration
• Started using debug version of libmpv
• Attach debugger to Flutter program (Task Manager > Right click Flutter app > Debug > Visual Studio 2022)

There are no obvious nulls in the local variables tab, and I don't have access to any pdb files to continue looking down the stack trace.

• libmpv-2.dll > libGLESv2.dll

Is there a way I can continue to debug this issue?

[isaacy13]

Have only had this pop up once, but also got a similar error from Angle

[isaacy13]

Integer division by 0

[isaacy13]

Unable to create ANGLE EGL surface

[isaacy13]

eglCreatePbufferFromClientBuffer is returning error 12302 whenever second instance calls

internal_handle_ seems to be getting allocated correctly, need to dig more into why it's causing error 12302

[isaacy13]

Current workaround is disabling hardware acceleration

However, will still dig into why ANGLESurfaceManager running into issues when multiple apps using media_kit at same time

[isaacy13]

As mentioned above, issue only affects when hardware acceleration is enabled

If you want hardware acceleration working for multiple instances, then here's my current workaround

• TLDR: synchronize reading & drawing between all AngleSurfaceManager instances (just make the existing mutex_ static)

I have no prior experience with graphics libraries, but it seems like since different instances are displaying different things, we shouldn't need to synchronize the instances

• prior to this change, only meaningful shared/static variable was instance_count_
• e.g.: this seems more like a workaround as opposed to a good solution

Perhaps someone with more graphics knowledge could explain why this works, and propose a better solution