6 Replies Latest reply on Oct 5, 2018 3:47 PM by Rich Fagioli

    Decal Issue: Problems with Multilayer Appearances

    Rich Fagioli

      Having serious issues with applying a decal to a cylindrical surface using multilayer appearances.

      Here is the effect that I am trying to achieve. However, this effect is only possible in "fast mode".

      Capture3.JPG

      When I try to render in "Accurate" mode, this is the result:

      Capture4.JPG

      Half of my multilayer surface disappears; sometimes ALL of it!

      I've used Brian Hillner's technique illustrated here: Bunkspeed Decals vs Texture Mapping - YouTube and followed it to a Tee. I've tried this technique dozens of times, using different permutation of .png images, jpegs, with different alpha layers, on SW models, self-created models, and the results are often similar and never as they should be. I've also tried importing my model in every possible way, extracting my part....or not.

       

      Generally, it appears that the alpha channel causes the surface on which it is applied to disappear. The decal remains, suspended on some invisible layer. Why does it do this and why does it seem to do this when I render in Accurate mode? I'm using Visualize 2018 SP4 standard. Here are a few settings:

       

      As always, any help would be greatly appreciated.

        • Re: Decal Issue: Problems with Multilayer Appearances
          Ron Bates

          Hi Rich,

           

          You are applying the ML appearance to the cylinder?  In order to get proper cylindrical mapped decal effect?  I'm confused about what you are actually doing here...    Perhaps you can share the .SVPJ.  I'd take a look at it directly.

           

          Hopefully you've seen in 2019, you can now directly use all mapping types for decals, allowing you to simply add the decal, cylindrical mapped, to any surface.  Avoiding any need to use this convoluted ML appearance workflow.

           

          R

            • Re: Decal Issue: Problems with Multilayer Appearances
              Rich Fagioli

              Thanks for replying Ron.

               

              All I want to do wrap a decal 180 degrees around a cylinder and that to do so I must create a multilayer appearance that includes my (.png) graphic and the corresponding alpha channel as a first layer, and the appearance of the native material as a second layer.

              There's really no project file to include....just create a cylinder model and apply any multilayer appearance that includes a graphic, alpha channel, and sublayer appearance.....as described at around 18:40 in this video: Bunkspeed Decals vs Texture Mapping - YouTube .

               

              What I'm trying to do is the following:

               

              If I use the proscribed way of doing this, I get the following:

               

              The top decal has been applied as a straight-up decal to a mostly flat surface, but the side decal is the problem. What I've ended up doing is simply duplicating that part of an identical model and applying my "appearance decal" to that surface; the alpha channel renders the rest of the part invisible...which is convenient. It's a kluged-together solution that works well enough, for now. I've just updated to 2018 thinking that my 2017 version was causing this problem, however, this problem as I described it above, is still present. If this issue has been resolved for 2019, then my question is moot.

                • Re: Decal Issue: Problems with Multilayer Appearances
                  Ron Bates

                  With my own setup, I'm not able to reproduce in 2018 sp03.  So again, perhaps if you can attach your own example, I can confirm if I'm seeing the same thing.

                  I'm actually surprised this works though considering you have to turn off Repeat to not get the texture image to...well...repeat.  But not repeating generally means the last pixels along an edge get repeated.

                   

                  This is moot in 2019, where you can simply add an actual decal (not a texture appearance as part of multi-layer), and control it's mapping.

                    • Re: Decal Issue: Problems with Multilayer Appearances
                      Rich Fagioli

                      Thanks for taking a look at this issue, Ron.

                      I've attached the svjp generated with the latest Visualize 2018 for you to try. I'm super interested to see what you come up with.

                        • Re: Decal Issue: Problems with Multilayer Appearances
                          Ron Bates

                          Hi Rich,

                           

                          I have a workaround for you case.  So I don't know the precise reasons why at this point, but we've always had some funky issues with MultiLayer and masking...  and for some reason in some cases, object scale plays a role.  The old planar mapped-only decals had issues around this scaling issue at times (in Accurate only) which is why I thought of this.

                           

                          And look, again, all this is moot, and WAY easier in 2019 with the new decal mapping controls; where it just works as expected. I was able to simply add your decal image as an actual decal, set to cylindrical, position and of course render in all modes correctly

                           

                          ...So...workaround.  Scale your model to 2.0.  (Re-Snap to floor).  Obviously you shouldn't have to scale your model and if you had attenuation-specific materials (thick glass, SSS) then you'd have to tweak those for the same look.  PITA.  But I think for you case, right now using 2018, scaling the model up may get you by??

                           

                          Hope that helps.

                            • Re: Decal Issue: Problems with Multilayer Appearances
                              Rich Fagioli

                              Thanks Ron. Appreciate the help.

                               

                              I guess I needed to know that it wasn't something that I was overlooking, or didn't understand. I'll give your work-round a shot after I get this batch of products rendered. Right now, I have a fix that works well enough, and is fast (detailed above, for anyone else having this problem).

                               

                              Just have to wait until we're eligible for the 2019 update.