Windows sized during creation are rendered incorrectly

Running the 0.26.3 client shows at the correct size - so this is probably related to using the RS APIs

Yes.

With the old APIs we resized the buffer stream in ApplicationSession::create_surface().

With the RS APIs we rely on the client to resize the RS, but we don't generate a resize event when we create the window at a different size than the request.

I'm not sure how much this opens the can of worms entitled: "what layout control does the server have over the layout of buffer streams and render surfaces"?

So this seems to be two separate bugs:
1) We render windows at incorrect sizes - the size that the shell sets should be the size that the shell renders the window at, regardless of what size buffer the client submits.

2) Our EGL demos fail to respect the size set for them by the shell.

The first seems to be a problem we should fix (even if only in our demo renderer). The second... is a problem, but do we need to fix it? Wayland clients won't be affected by it...

Last time I worked on this problem (and fixed it), I found the initial resize event design was racy and unreliable. So don't rely on that. What you should be able to rely on is the EGL_WIDTH/HEIGHT being consistent with your target buffer, so maybe more work needs to be done on the Mesa/RS side...

For more details, see the fix for bug 1686620:
https://code.launchpad.net/~vanvugt/mir/fix-1686620/+merge/323378

And the first relevant report from last January: bug 1655804

@chris

There's been a longstanding debate about how we handle rendering content a client places outside the window area. I think the team now agrees with you, but I don't know if we want to tackle it for 0.27.

The linked MP fixes the second problem, plus the potential deadlock introduced by -c 4150.

Fix committed into lp:mir at revision None, scheduled for release in mir, milestone 0.27.0