For example, lightning will strike a raised 15 by 15 log platform even with a stone pillar in the middle.
If the platform is constructed on a large flat area, lightning will not strike around the platform.
If a pillar is made on a flat area with no raised portion, lightning will not strike around the pillar.
I tested this by setting the weather to “thunder”.
Screenshot of a platform after several hours:
Spoiler
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