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[Blender] Floating graphic on object from an alpha png in Cycles

I'm a beginner in Blender and am doing the BlenderGuru donut tutorial(doing the cup portion of the old one and geometry nodes sprinkles of the new one), but wanted to do something more by adding a Homer Simpson pic on the larger plate(surrounded by donuts on the edge, but irrelevant to this). Problem is I can't find why the texture seems to levitate right above the object, even causing a shadow, while rendering in Cycles. In Material Preview mode it shows up level with the plate exactly as it should.


Here are a couple pics showing things. Let me know if I need to provide more info. Thanks for your help!


Replies

  • rexo12
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    rexo12 greentooth

    I assume you're using a plane to project this?

    First thing would be to check that it is actually level. What does it look like in Orthographic view? You can also snap the cursor to some vertex on the plane and check its location in the N->3D Cursor panel, then verify that snapping to a vertex on the plate doesn't change the Z location significantly.

    You can try using a Shrinkwrap modifier to project the plane onto the plate, but you will still have to offset it ever so slightly to prevent Z-fighting.

    Why not map the image to the plate UV's directly?

  • Polygonorous

    Thanks for your response.

    I used texture stencil mapping over the plate. I don't know if that's the same thing as projecting with a plane. I assume that's using a flat square with the image and applying it to the mesh itself?

    The pic below shows what I used.


  • okidoki
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    okidoki triangle

    The Material Preview usually casts no shadows so you can't see this and because you set the alpha of the image to control the complete alpha of your material your plate would be transparent outside of homers head. So i assume you have some geometry copied and must have accidently elevated this a bit. You don't need this if your image alpha controls the mix factor (Fac) between the plate color (a simple RGB node with the white color of the cup) and the image.

  • Polygonorous

    I quintuple checked in various ways and I don't have any extra geometry, overlapping, non manifold, or w/e else. It seems it's making the top layer of the plate the whole alpha like okidoki said, so it seems to be working similarly to how the alpha on a plane would work like you both are saying. I posted a couple pics that shows the bottom border of the plate being deformed and being able to see it through the alpha'd top border of the plate with a levitating homer head where the top level is that I want to be solid.


    @okidoki: ...So after some trial and error and realizing the lighting was throwing me off on the decline at the edge, it worked! Thanks a lot!




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