Myst3: J'nanin Reflect Light Source Wheel Counter-Clockwise Turn Animation Broken

[wataniyob]

The animation for counter-clockwise rotating the wheel controlling the light source for the reflector puzzle on J'nanin does not play (rotating the wheel clockwise correctly shows its animation).

Steps to reproduce:

• Go to the wheel which controls the direction of the light source for the reflector puzzle on J'nanin at the start of the game
• Turn wheel counter-clockwise by clicking on the bottom or left handle of the wheel

ScummVM version: 2026.2.1git25414-g975ae070509
Language: English
Version of game: DVD, game files from GOG
OS: Windows 10 build 19045.7184, 64-bit

[wataniyob]

Save file at the light source wheel

[wataniyob]

Correct misspelling of ScummVM in description.

[antoniou79]

Right. This must be a regression from my recent changes in the movie playing code paths.

2026.1.0 does not have the issue, but 2026.2.0 does.

I'll prioritize to investigate this.

[antoniou79]

In a8fc4de3:

MYST3: Fix Jnanin wheel's counter clockwise turn regression

Fixes #16757

This plays the movie backwards by continuously writing to the _nextFrameReadVar. We need to drawNextFrame in this case (if different than current), but not set the _isLastFrame flag, which would otherwise be set, since we start from the end going backwards.