Smoother gameplay on every floor

This update rebuilds how the game draws the world. You should feel the difference right away, especially in the mountains.

Improvements

• Walking on high floors and around mountains is now smooth: the world scrolls instead of being redrawn every few steps.
• The work of drawing the world is now spread evenly across frames, so the small hitches that remained while walking are mostly gone.
• Climbing and descending stairs is faster.
• Torches and other animated objects no longer slow the game down.
• Creatures far off screen are no longer drawn.

Fixes

• Fixed a black screen that could appear after a long session among the mountains, leaving only names and health bars visible.
• Fixed parts of the floor that could stay empty for a few seconds after taking a stair or arriving in a new area.
• Stairwells inside mountains and dungeons now have a proper frame, with no gaps around them.

If you still notice stutters or graphical glitches, please tell us where they happen.