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Treat building shadow light sources same as terrain, from NW?

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#1
David Medeiros

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Does the advice to always place the light source in a map at the top left (roughly 315 on a N facing map) apply to maps with building footprints only?

 

I'm critiquing a map with no terrain but building footprints that are cast to the upper left instead of the lower right, and it's driving me nuts. But... I can see lots of examples of shadows cast in all sorts of directions.


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#2
Daniel Huffman

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I would think so. Are these drop shadows or something similar? I always put drop shadows on the bottom right (that is, lit from the top left). I think it probably ties into the same weird brain thing that makes us see inversion when a shaded relief is lit wrong. If it's a simple shape like a building, it's probably less likely to cause trouble, but it's still not quite right.

 

Here's a related example, attached: I often like to do a bevel effect on water (though usually much more subtle than in this example). If I put the shadow on the top left, it looks like the water is sinking into the land. If I switch it, it looks like the water is popping up. So, that's an example of lighting angle causing interpretation problems for something other than shaded relief. It's the same basic principle.

 

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#3
David Medeiros

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It's a hard drop shadow, like you'd see in ArcGIS. It won't really create inversion, but seems wrong anyway. I gave them feedback asking for the orientation to be changed, but wanted to see if this was a solid a best-practice for buildings as it is with terrain. Thanks!


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