Problem rendering glass in Cycles

posted to: Rendering Glass

Hi, any idea why I get these weirdly placed reflections when rendering glass?  It should be transparent and I should be able to see the windows through the glass handrail... I used the architectural glass material setup, my glass has thickness and normals are facing the right way. 

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  • spikeyxxx replied

    Sorry to ask, but are you sure you are using Cycles?

  • Alexandra Enescu(alendomata) replied

    Yep, I'm sure

  • spikeyxxx replied

    It's just that, amongst other things, there appears to be some shadow missing from the tree and that is typical for Eevee....

  • Alexandra Enescu(alendomata) replied

    The tree is from botaniq add-on, not sure if that influences the shadows - i'm a newbie to both Blender AND the add-on, so not sure...

  • spikeyxxx replied

    Okay, that's Cycles allright.

    What is the IOR of the Glass Material?

    Maybe post a Screenshot of the Shader Editor.

  • Alexandra Enescu(alendomata) replied

  • spikeyxxx replied

    Seems pretty normal to me, actually. That's the way glass bends light:

  • Alexandra Enescu(alendomata) replied

    Thing is, when I use just the simple Glass BSDF, the offset is nowhere near as pronounced as when I use the architectural glass setup. Any idea why that difference exists between the two? 

  • spikeyxxx replied

    OMG, you are absolutely right! This should NOT happen.

    I also tried this in 2.79 and:

    versus:

    I don't have time to look into that this weekend, msut finish this month's Challenge, but that looks like a bug (and an old one as well!). No idea why nobody ever noticed this before.

  • spikeyxxx replied

    Oh no, I was sleeping :)

    The problem is, that your glass has thickness and and the light ray changes from a Camera Ray to a Transmission Ray. 

    Either use a Plane for the glass, or add the Transmission Rays to the Camera Rays :


    2 loves
  • Alexandra Enescu(alendomata) replied

    Thank you sooooo so much! It's working great now. 

  • Wendy Robinson(wendy10698) replied

    spikeyxxx I hope I’m as knowledgeable as you some day. 😎