Random rant of the day

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A couple of details made me waste some time till I figured them out. First one was an issue with povray 3.7 running on Linux that would preview a black background when I wanted a transparent background. Output was a PNG file and the final result was ok, but I failed to notice that there was an error with the command temporary output to the display and not with the final rendered file. I noticed the problem once I ran the same command with the same files on my Mac and preview shown the checkered pattern of a transparent background.

used with permission

But this does not mean the Mac versions are any better: Second problem, using Meshab 2016.12 version it was impossible to get a snapshot with a transparent background either. It appears it is a known issue too.  Same version of Meshlab but running in Ubuntu worked like a charm.

I had a third problem I can only blame myself for: it turns out STL files and Povray use a different coordinate space, so my renders appeared flipped horizontally. Nothing that ImageMagick cannot fix (convert -flop).  And yes, y-axis is up on povray, so instead of figuring out how to fix that there I just rotated the rendered bitmap so it looks z-axis is up instead.

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