I tested this and I get the same result: in AC17 when I save the 3D Viewpoint as JPG (Color - Quality: 90), the resulting image is fine, the slanted lines are nice and show no jaggedness, they look like they do in the 3D Viewpoint.
However, when I do the exact same thing in AC19 with the same settings, lines in the resulting JPG will become jagged, as if antialiasing was not working. What is even interesting is that right after ARCHICAD finishes saving the JPG, the 3D Viewpoint becomes just as jagged as the resulting JPG. However, if I zoom in and out a bit the correct antialiasing is restored.
Out of curiousity I tried the same thing in AC18 and I found that it was working fine in AC18 as well.
So there is something definitely going on here which was working in previous versions and not working in AC19. This was tested in build 5005, which is currently the latest build.
I will forward this to GRAPHISOFT for investigation.
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