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.

The issue is that, during the credits that play after the main menu has been idle, half of the background is black and the other half is the bottom half of the main menu.

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.

I am attaching screenshots of the low res and high res credits. (The high res credits are "expected" to be more glitchy since due to another issue (https://bugs.scummvm.org/ticket/13134), the yet unused NPCs are seen all grouped to the left -- this ticket is not about that issue).

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.

[mgerhardy]

85d3666364bc75966e992cc5ebd07b6a585eed6c during bisecting I found this commit that is somehow related - leaving the credits scene with esc will enter the menu with the wrong palette.

[mgerhardy]

8ac2ed039fc3e3a3bbdf373d309153bee67b306b caused the problem

The removal of the _engine->_screens->clearScreen(); call most likely - but I can't find this in the original sources - need to investigate

[mgerhardy]

fcab03efd6cda1c023456632f608196900bd06c3 fixed the issue - thanks for the report