* Flip the tiles by 90 degrees

* Fix stairs rendering

This fixes bad lighting on the sand, but tiles are "mirrored" from their look in gui_blocks.png. But this is an overall better state :)

source/Minecraft.cpp

@@ -513,6 +513,8 @@ void Minecraft::tick()
 			_levelGenerated();
 		}
 
+		SandTile::instaFall = false;
+
 		if (m_pLevel && !field_288)
 		{
 			m_pGameRenderer->tick();