@benreynolds4 (benreynolds4) posted a new topic, subject "converting shadows to geometry (updating in real-time)". It read:

   Hi everyone,
    
    I have seen a demonstration of someone using a city model and with a direct light targeted to a specific site and the shadows of the building on this site turn into geometry - and when the light is moved - the shadows are updated in real-time.
    
    does anyone have any ideas on how to achieve this?
    
    ben  
    www.palacepalace.com

To which @errantspark (errantspark) replied

    Why would you want to have such an effect?

After which, @thatoneguy (thatoneguy) added

    Either I'm not understanding you or else this person was using some kind of insane script.
    
    I think I'm misunderstanding you because that sounds like an impossible task.

@benreynolds4 (benreynolds4) replied

    you'll see what i am talking about here.
    
    it's in section 5.4:  
    pgs 15-16  
    http://www.haw.com.au/wah/MWhite-Towards-Sustainability.pdf

So @DaveWortley (DaveWortley) replied

    You need a shadow alpha, not geometry. Look up rendering shadow passes with matte/shadow materials.

@CGTalk_Moderation (CGTalk_Moderation) replied

    This thread has been automatically closed as it remained inactive for 12 months. If you wish to continue the discussion, please create a new thread in the appropriate forum.


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