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#11 Imperfect Alpha translucency for unofficial part 60616a
This is really not a bug, but I wanted to get doc and tracking on what's going on. A translucent 60616 door looks fugly in BrickSmith - you can see diagonal artifacts.
It turns out these artifacts are Z artifacts - the door's interior is modeled out of multiple trapezoids (to "cut out" the door handle" in a manifold manner), and each triangle ping-pongs from the front to back face. The result is that the parallax-visible edges between the pairs has different Zordering (and alpha) and makes errors.
I don't know that there's anything that can easily be done - the LDraw spec doesn't require authors to order their parts in a particular way, and I don't have an algorithm in mind that would help Bricksmith reason about these cases.
POSSIBLE EXCEPTION: real BFC support would let Bricksmith simply cull the entire back side, which would make alpha translucency pretty consistent for manifold shapes. For multi-layer shapes we would still need some other ordering - perhaps a pseudo-radial sort would work.
