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106

General Discussion / Re: Bay12 Classroom

« on: December 07, 2016, 11:12:38 pm »

Quote from: Dozebôm Lolumzalìs on December 07, 2016, 11:07:31 pm

Quote from: Gatleos on December 07, 2016, 11:04:22 pm
I'd be interested to know how many bay12ers have actual experience in teaching. I know there are at least a couple.

My current job is like teaching but with worse pay, I don't count.
Pay is irrelevant. Your income is not currently a good measure of your skill, aptitude, or benefit for society. (this is a problem btw)

I tutor computer science students, which requires the same kind of skills as a professor I guess, just to a massively different degree. What I mean is that I'm wondering if anyone around here has legit, professional teaching experience; Bay12 seems oddly skewed toward that demographic.

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General Discussion / Re: Bay12 Classroom

« on: December 07, 2016, 11:04:22 pm »

I'd be interested to know how many bay12ers have actual experience in teaching. I know there are at least a couple.

My current job is like teaching but with worse pay, I don't count.

108

General Discussion / Re: Election Day, USA!

« on: November 09, 2016, 02:03:58 am »

Quote from: Aklyon on November 09, 2016, 02:02:13 am

Quote from: Gatleos on November 09, 2016, 01:59:58 am
This is the backstory to a cyberpunk dystopia
Or LCS, as described in the other threaf.

...

Oh GOD

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General Discussion / Re: Election Day, USA!

« on: November 09, 2016, 01:59:58 am »

This is the backstory to a cyberpunk dystopia

110

General Discussion / Re: if self.isCoder(): post() #Programming Thread

« on: October 05, 2016, 08:38:15 pm »

I just looped through every possible combination of a-b, none of them offsets the polygon for the correct amount. Thanks for the help anyway, I'll try to think of something else.

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General Discussion / Re: if self.isCoder(): post() #Programming Thread

« on: October 05, 2016, 01:30:15 pm »

Quote from: MagmaMcFry on October 05, 2016, 11:10:11 am

The Minkowski difference A - B is the set of all pointwise differences {a - b : a in A, b in B}. A vertex of the difference must be the difference of two vertices. For example, if a is the topmost vertex of A, and b is the bottommost vertex of B, then a-b is the topmost vertex of A-B. However not all differences of vertices are vertices of the difference. Make sure that the vertices you're using for aligment actually correspond to each other.

Yeah, that's the problem. I start with convex polygons whose edges are sorted so that the edge with the smallest theta comes first, and I merge the lists. Each vertex is just offset from the previous one, so the only offset I need to compute is the first one. So right now, the first vertex I add is at the origin. That point could either be from polygon A or B, so which points should I be subtracting to get the offset for it?

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General Discussion / Re: if self.isCoder(): post() #Programming Thread

« on: October 05, 2016, 10:52:59 am »

Spoiler (click to show/hide)

So I'm trying to detect collisions between the two convex polygons at the top left. The magenta polygon is the Minkowski difference of the other polygons (derived by inverting polygon 2 and merging the list of edges, sorted by angle). If the polygon (translated by the relative positions of the input polygons) crosses over the origin (cyan cross), that means they are intersecting.

I got the shape completely right, but for some reason it doesn't line up correctly with the origin. I tried computing the centroid and offsetting by that, which almost works, but it's still off by a bit somehow:

Spoiler (click to show/hide)

The cross should be right over that closest vertex here, but for some reason the polygon is shifted slightly to the left. I just can't seem to find a formula that offsets it for the right amount for any pair of polygons.

Any ideas?

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