TWINE: Glitched background during main menu idle credits (Regression, Sort of)

[antoniou79]

This was tested on Windows 10 with a recent build of ScummVM 2.9.0git from master HEAD and the GOG version of Little Big Adventure.

How to reproduce: Launch the game, wait till it gets to the main menu, then leave it on idle for about a minute. The game's credits will start rolling automatically, and the end credits music is playing.

The issue is that half of the background is black and the other half is the top half of the main menu.

I am attaching screenshots of the low res and high res credits. (The high res are "expected" to be more glitchy since due to another issue (...), the yet unused NPCs are seen all grouped to the left).

This looks like sort of a regression from what happens in 2.8.1, albeit the daily build has some improvements.

In comparison the 2.8.1 ScummVM rolls the credits after the main menu has been idle for only 15 seconds (too fast), and also no music is playing during the credits. But it has a full black background.