It is by the same author who created Ottercast[0] and has apparently been developed during GPN[1], a Chaos Computer Club event in Karlsruhe, Germany that ended two days ago.
Meta: there's a tiny typo in the title, "marked" should be "market" (as in flea market). I would suggest simplifying it to "Ligra: open source image projector from flea market parts", or something.
I once built a DIY beamer out of an old overhead projector and an old 1024x768 pixel TFT screen. Basically, I removed the backlight of the screen, used the raw screen instead of the glass table, and put an extremely bright metal halide lamp and several fans into the projector. This was 20 years ago when beamers where quite expensive, and this one cost around 60 EUR. It worked very well, the picture quality was amazing, and I used it for some years. You could also heat an entire room with it!
You still haven't explained me how that message is anti-european or solicit violence against the native population. That's like saying being pro freedom of religion is like being against Christianity.
Regarding the events in the article you linked: I haven't been following them, but from the look of it it seems the attacker could be very well an Islamic extremist. Being an advocate for immigrants rights doesn't mean someone cannot be also against religious extremists.
Always this stuff... Seriously, let's look at Germany. Do I feel less safe than before because of some refugees which cannot behave? Yes. Has there been more crimes than before committed by refugees? Yes. Do we have increased gang activity related to immigrants and refugees? Yes. Am I a bit racist? Sadly, yes (I did several scientific tests which prove that I am).
Not for the world would I close the border to not let refugees in. You simply cannot judge anyone for their birthplace. The message is absolutely correct, no human being can (should) be illegal, especially when in need.
