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On the topic of the apriorisms in economics:

Exponential Economist Meets Finite Physicist: https://dothemath.ucsd.edu/2012/04/economist-meets-physicist...

A Lost Century In Economics: Three Theories Of Banking https://www.sciencedirect.com/science/article/pii/S105752191... (Results re-affirmed by several central banks after publishing)

Sonnenschein–Mantel–Debreu theorem (microeconomic rationality assumptions have no equivalent macroeconomic implications) https://en.m.wikipedia.org/wiki/Sonnenschein–Mantel–Debreu_t...


Obligatory reminder that money != coinage != barter != banking


Hm. I have to say I think this isn't quite right. I guess it is, strictly speaking, true that these concepts are "!=". However, I think that the vast, vast majority of people err on the side of thinking that they're far more separate than they actually are. Money, coinage, banking, and debt (I'm ignoring barter here and adding debt) are so intimately related that, really, none of them exist in anything resembling their current iterations without all the others. And talking about "money" in the sense of exclusively a medium of exchange is really hard for people these days to wrap their heads around...none of us have had any experience with such a thing whatsoever.

All that said, I'd be curious to hear you expand on your original comment. How are you defining each of these things? What are you trying to say by noting that they're not equal? What are the implications?


> It's interesting to note, that when Obama used the platform to get elected, no one minded. But, when the opposing party does it, everyone judges it negatively.

When history sandwiches you between two world leaders with an apparently combined IQ of 2, people might let some questionable things slip.


When one wants a “real” person or theory, one strays as far as possible from the unreality-generator that is “academic” economics.

If one would mount an axle on Smith’s grave, we could live off free energy for millenia.


Techniques as in workflow? Algorithms? At which point does something become “unreasonable” vs simply effective.


Try to spend as much time with friends and family as I can manage.


Yes. This is why it’s good to seek out alternative opinions. Having a network of advisers can be very helpful.


Parallax mapping will not benefit from this, since the limiting factor there is performing a raymarch on a heightfield to find an exact intersection. At every step along the ray you need to test wether you are inside or outside of the heightfield. This means offsetting the uv coordinate (xy position inside the texture) by the ray vector, and then using that coordinate to sample the texture again, to check whether or not you penetrated the heightfield. The amount of texture lookups quickly becomes the bottleneck, especially on large textures since they incur cache misses. To give you an idea: for every parallaxed pixel on the screen the heightmap texture might be looked up several dozens of times. You don’t nearly get to subpixel accuracy before performance grinds to a halt. Parallax mapping is view dependent, so roughness mapping, even if somehow applicable would need to be highly anisotropic for it to work, which means a huge storage cost.


> for every parallaxed pixel on the screen the heightmap texture might be looked up several dozens of times

I didn't realize it was on the order of dozens. Just to clarify, we're talking pixels and not texels, right? This isn't dependent on the resolution of the map?

> roughness mapping, even if somehow applicable would need to be highly anisotropic for it to work

I didn't think about that, I guess you're right. How huge, exactly? Seems like something you could compress very well if you combine textures into a larger megatexture.


It’s an additional texture fetch on the gpu, it’s virtualy free if you discount storage costs. It’s been in games for years.


Additional texture fetch is by no means free but when the alternative is 100x SSAA you can get away with a lot.


PBR has seen commonplace adoption in games since 2012. Roughness mapping has been used for years in real time engines.


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