Unable to get/set window position on MouseMoved callback

[dark-steveneq]

So for context I'm writing my own GUI framework of sorts (rendering sprites to an undecorated window with transparent framebuffer) and now that I got around to implementing window dragging its a workaround hell. Doing anything with SetPos() and GetPos() in MouseMoved freezes everything for some reason. I have *opengl.Window in my own struct if that even matters.

[bhperry]

from MouseMoved callback?

[dark-steveneq]

Yup

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[bhperry]

Pixel uses a package called mainthread to interact with openGL to ensure all calls come from the same thread (required by OpenGL). The callbacks are processed from within a mainthread call, and the SetPos and GetPos also use mainthread calls, so they end up getting blocked on each other. Doesn't know that it's already running in the scope of mainthread, just blindly pushes the requests onto the call queue

[dark-steveneq]

So I can't use both functions in that callback because they would cancel each other out and freeze the process/loop indefinitely?

[bhperry]

In its current state, yes. This is a pretty good argument that the user callbacks should be run outside of the mainthread context though. Would have to collect the events as they are received and process them after. But then you could use any window function from within the callback.

In the meantime, you could do something similar. Keep track of the callbacks you received each frame, and process them after win.Update()