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"The program should, in some way, expand the concept of what computer paint programs are, as well as what mark making can be."

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Omar Rizwan @omar

Debugging 3D calibration... had weird issues where it produced homographies with det(H) < 0 which totally messed up the rotation and translation (you'd have a couple calibration poses that have z < 0, so 'behind the camera' or 'behind the projector' and reflected, which I guess makes mathematical sense but not physical sense lol). I just set H = -H and then it fixed everything

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Omar Rizwan @omar

All computer vision stuff is like

Step 1. Do some linear algebra that makes logical sense, uses a rational scientific model of how we believe the world works, looks reasonable

Step 2. The result of Step 1 is basically garbage. Feed it into a nonlinear optimizer to make it actually good

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Omar Rizwan @omar

Rotation Averaging https://users.cecs.anu.edu.au/~hartley/Papers/PDF/Hartley-Trumpf:Rotation-averaging:IJCV.pdf

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Omar Rizwan @omar

stubbornly calling it `rotationVectorToRotationMatrix` instead of `Rodrigues`

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Omar Rizwan @omar

Also wondering if this technique would help with RFID stuff -- I hadn't realized that there is this same problem of discrete ambiguity even in visual marker tracking https://social.omar.website/@omar/statuses/01J0F5H0GW4HMG3G6B5RR0TQ9T

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Omar Rizwan @omar

Been reading about "Virtual Visual Servoing" http://rainbow-doc.irisa.fr/pdf/2002_eurographics_marchand.pdf -- maybe the most convoluted way to explain a smoothing/filtering algorithm (?) that I've seen lol

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Omar Rizwan @omar

What is a car mouse

¢ Rated voltage: AC 125V-250V; Current rating: 5A

¢ Application:Apply in A computer mouse, car mouse, automobile
electronic products, communications equipment, military products, test
instrument, gas water heater, gas burner, small home appliance,
microwave oven, electric rice cooker, floating ball supporting
equipment, medical equipment, building automation, electric tools, ect.

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Omar Rizwan @omar

(I'm sure people who've actually used CAD software know this:)

CAD software is fascinating honestly, it's basically
programming

You replied to yourself

CAD software is fascinating honestly, it's basically
programming

it has 'parametric history’, like if you make a hole
in an object and then copy and paste it so there
are 4 holes, you can then select any of those
holes later and it'll filter the undo history to only
operations that affect that hole

and you can go back to the original operation
where you created the original hole and adjust the
size, make it bigger or w/e, and the new size will
propagate through the history and change in all
the copies also

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Omar Rizwan @omar

one of the subtleties in this area is I found that in Folk you generally want semantics that are more like a condition variable or signal than like a blocking channel -- you raise it, they get notified if they're waiting on it, but they don't queue up if you raise it multiple times in a row
we initially used various pipe/channel/message stuff (both Tcl and Unix/TCP/websocket), but I found that I ended up spending all my time trying to find weird blockages and latencies that emerged from that
shared memory provides a much more reasonable default that matches the Folk statement/database semantics
where the reader can miss intermediate states and it's ok

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Omar Rizwan @omar

my current understanding is that both clang and gcc basically support nested functions / closures but with different and incompatible syntax and implementation… wonder if people ever just ifdef between them

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