@Estivo, not exactly does it work the way I wanted.
I give bigger framgnet map and more situations.
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1. m_renderLightOverHull false, m_transparency 0, redrawing walls.
Bad: Whole labrinth can be seen, all walls have same brightness.
2. m_renderLightOverHull true, m_transparency 0.
Bad: Shadows on walls.
3. m_renderLightOverHull true, m_transparency 0.5.
Bad: Shadows on walls, light in separated chamber.
4. m_renderLightOverHull false, m_transparency 0.
Bad: Walls are unlighted.
5. m_renderLightOverHull false, m_transparency 0.5.
Bad: Walls are unlighted, light in separated chamber.
I'm trying to get situation from picture number 2, but without shadows on wall but still have darkens out of room.