sketchucation logo sketchucation
    • Login
    🤑 SketchPlus 1.3 | 44 Tools for $15 until June 20th Buy Now

    Refractive Caustics (Pool Water) - Weird Cutoff?

    Scheduled Pinned Locked Moved V-Ray
    renderpluginsextensions
    6 Posts 4 Posters 5.7k Views 4 Watching
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • saberopusS Offline
      saberopus
      last edited by

      Hello, everyone. I've got a basic water material w/ displacement for caustic refractions. This seems to be working, in general, but I'm seeing an unexpected 'cutoff' where the lighting on the bottom of the pool suddenly changes along a line.

      http://i.imgur.com/YisjSxo.jpg

      http://i.imgur.com/oTcYuur.jpg

      http://i.imgur.com/isSNqg5.jpg

      In the past, I've had issues w/ the caustic Photon Radius setting, where the entire model needs to be relocated to the -x,-y quadrant with respect to the default model origin. In those cases, where part of the water surface is out of that quadrant, and part is in, I've seen this line. But obviously the caustic effect is being applied to both the lighter and darker ends of the pool in this image...

      I've got a dome light (spherical HDRi sky) and the Sketchup sun at .3 providing the light.

      Any ideas? Let me know if more information is needed.

      Thanks!

      1 Reply Last reply Reply Quote 0
      • filibisF Offline
        filibis
        last edited by

        Can you share your water material settings?

        I would suggest increasing Photon Emit Radius under Sun options but you already mentioned and aware of that. Maybe try disabling Affect Shadows parameter of water material?

        Check the official manual, you might get a clue: https://docs.chaosgroup.com/display/VRAYSKETCHUP/Caustics
        https://docs.chaosgroup.com/display/VRAYSKETCHUP/V-Ray+Sun+and+V-Ray+Sky+%7C+SunLight


        And make sure that there is no invisible plane or something contributing to the shadows etc.

        1 Reply Last reply Reply Quote 0
        • saberopusS Offline
          saberopus
          last edited by

          Thanks, filibis. Here are the material settings:

          http://i.imgur.com/g0jdFsl.jpg

          Nothing in the manual has clued me in to a solution, yet. I am going to try disabling Effect Shadows now.

          1 Reply Last reply Reply Quote 0
          • saberopusS Offline
            saberopus
            last edited by

            Well, uh, it seems I've solved the problem by shifting the entire contents of the model to the -x,+y quadrant w.r.t. the default origin. Why this works, I don't know... nor do I know why the cutoff was where it was before, because it did not occur along one of the default axes, but at something like a 45 degree angle between -x and -y.

            1 Reply Last reply Reply Quote 0
            • N Offline
              nowd1976
              last edited by

              Hi, everybody. I have a fundamental water material w/uprooting for acidic refractions. This is by all accounts working, when all is said in done, however I'm seeing a surprising 'cutoff' where the lighting on the base of the pool all of a sudden changes along a line.
              Just check polygroup summer waves elite pool

              1 Reply Last reply Reply Quote 0
              • F Offline
                freebs
                last edited by

                TL;DR version:
                Go into LIGHTS -> Sunlight -> Caustic Photons and change the EMIT RADIUS there. The units are in your model units. And the center starts from the sun's location.

                Full explanation:
                Vray projects a beam with an 'Emit radius' when rendering caustics. Where that edge ends, you'll see a cut-off line.
                In 3ds max you can set this emit radius' direction and size visually. Buuuht, not here.

                In Sketchup the sun is the emit source, so depending on time of day(!) you'll have to fiddle with the emit radius.

                The attached image has three swimming pools: at 34' from the origin of the blue axis (0,0,0), then again at 60' and again at 90'.

                At 1:00pm the sun catches all the pools nicely, but the 2d and 3d pools aren't getting enough caustic photons to show caustics properly (top half of image), because the emit radius is set to 700, which doesn't extend far enough.

                NOTE: The units of this model is inches, so that's 700 INCHES or 58.3'. The yellow circle has a 59' radius, and you can see the 'dark line' cutting through the pool.

                The second render shows the emit radius set to 1080" (90'). This time the third pool is captured and begins to render caustics.

                Tadah!


                vray 3.6 sketchup causticss affected by emit radius setting under Sun->caustics menu

                1 Reply Last reply Reply Quote 0
                • 1 / 1
                • First post
                  Last post
                Buy SketchPlus
                Buy SUbD
                Buy WrapR
                Buy eBook
                Buy Modelur
                Buy Vertex Tools
                Buy SketchCuisine
                Buy FormFonts

                Advertisement