I can easily import transparent PNGs into Rhino (v6). It is great for the front face of buildings. But in rhino, the upper edge has a faint pixel line. You can see it in rhino itself and in my render program (simlab composer) I checked it in photoshop an affinity photo, it is 100% transparent on the edges.
but for the sake of the future, i would also prefer not to slice it off. @pascal@stevebaer can you confirm that this is a bug, or what is happening here. i tried png with all sorts of settings, non yield an image without boarder, all pngs where clean at the edges.
Did you check the alpha channel? From the looks of the screenshots it’s not a consistent artifact, it would seem to in fact be in the files, that’s why you should post one for them to check.
the bottom pixels are repeated so looks like a mapping issue to me
edit: below the same image but then with 1 extra transparent row at the bottom solves it:
@bodzguard thank you for the image. I indeed can see the line with this image - I haven’t figuret yet out why. It does look like a mapping problem as @Gijs suggests. The weird thing is that I even see it even with Raytraced.
@nathanletwory this is probably a stone age old bug, since sure longer as i use rhino 10 years. just to be sure i understand correctly, it is not only the last line but actually all around the boarder
isn’t this the default behavior with tiled textures - bi-linear interpolation works on ‘centers’ of pixels - so what in the grid view is a pixel, once interpolated becomes the center of a bi-linear interpolation?
I saw this long ago in rhino, and wanted to report it, but after closer inspection i realized that it is inherent to how textures are drawn.
Still it would be nice to have a ‘repeat’, ‘clamp’ and mirror option in textures uv (respecting transparency)
in other words - i noticed this when trying to solve a problem with ‘pixel perfect’ textures, just to realize that the pixel that had a left top corner of 0,0 in opengl (and any similar context) was suddenly at 0.5 / 0.5 and would always have to take the missing information part from the ‘other end’ when set to repeat, which is the default
That is strange, I see the same with that file. BUT when I tested with a simple PNG from the net and I do not see any artifacts along any edges. Neither when used as a picture object nor if added as a material with or without repetitions.