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Scratchapixel 4.0, Learn Computer Graphics Programming

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Re: Scratchapixel 4.0, Learn Computer Graphics Programming

#31

Post by jagged-chisel »

penteract wrote: post #23
jagged-chisel wrote: post #22

Earlier quoted context omitted.

> "...vision occurred through beams of light emitted from the eyes, interacting with the environment" How did they explain lanterns and torches in this theory?

Until you can observe that light doesn't travel instantaneously, it would be consistent to believe that a beam leaves your eyes, bounces off a surface, and informs you (as though it were a limb, perhaps) when it hits a light source.

The more I think about it the weirder it gets.

It’s day time, the sun is up, it’s a cloudless day. Ambient light is bouncing all over, including into a south facing window (i.e. no direct sunlight.) How does the Eye Light Emitter do its job in this case?

Now, I don’t mean “this concept is impossible” because that’s clear. I’m genuinely curious how this would have been explained by someone at the time.

Re: Scratchapixel 4.0, Learn Computer Graphics Programming

#33

Post by ofrzeta »

meindnoch wrote: post #27
prmoustache wrote: post #20

Earlier quoted context omitted.

I would say generating chapter thumbnail images for a non artistic publication is probably the best use case for AI.

It isn't, because people associate these kinds of pictures with low-effort auto-generated clickbait and scams.

"people" as in "some people on HN"? Because I think as broader audience wouldn't necessarily mind or associate those images with scams.

Re: Scratchapixel 4.0, Learn Computer Graphics Programming

#34

Post by _a_a_a_ »

meindnoch wrote: post #25
jagged-chisel wrote: post #22

Earlier quoted context omitted.

> "...vision occurred through beams of light emitted from the eyes, interacting with the environment" How did they explain lanterns and torches in this theory?

What do you mean lanterns and torches? On the macroscopic scale, light rays can be replaced with vision rays, and everything works out the same. That's how ray tracing works. People thought eyes were doing ray tracing.

What do you think he means? It's a good question.

Re: Scratchapixel 4.0, Learn Computer Graphics Programming

#35

Post by Vegenoid »

SapThePixelFox wrote: post #12
atan2 wrote: post #7

I would personally try to have some non-AI thumbnails. But that's just me.

)) The AI-thumbnails will be removed in a few weeks. Totally agree with you.

Just remove the images now, until you have real ones.

I've seen several blogs/sites of decent quality and technical depth start throwing random semi-related generated images into their articles, and it just makes me immediately wary of BS. No images is better than AI-generated ones if you want your site to look like it was made with care and has good information on it.

Re: Scratchapixel 4.0, Learn Computer Graphics Programming

#36

Post by HideousKojima »

jagged-chisel wrote: post #22
susam wrote: post #5

An interesting excerpt from the section “3D Computer Graphics Primer”: > The understanding of light and how we perceive it has evolved significantly over time. Ancient Greek philosophers posited that vision occurred through beams of light emitted from the eyes, interacting with the environment. Contrary to this, the Arab scholar Ibn al-Haytham (c. 965-1039) introduced a groundbreaking theory, explaining that vision r…

> "...vision occurred through beams of light emitted from the eyes, interacting with the environment" How did they explain lanterns and torches in this theory?

I remember a guy who had a novel theory (mostly as a joke, I think) that light bulbs don't emit light, they simply suck away the darkness. He literally called lightbulbs "darksuckers."

Re: Scratchapixel 4.0, Learn Computer Graphics Programming

#37

Post by Phrodo_00 »

jagged-chisel wrote: post #22
susam wrote: post #5

An interesting excerpt from the section “3D Computer Graphics Primer”: > The understanding of light and how we perceive it has evolved significantly over time. Ancient Greek philosophers posited that vision occurred through beams of light emitted from the eyes, interacting with the environment. Contrary to this, the Arab scholar Ibn al-Haytham (c. 965-1039) introduced a groundbreaking theory, explaining that vision r…

> "...vision occurred through beams of light emitted from the eyes, interacting with the environment" How did they explain lanterns and torches in this theory?

A far as I know, in raytracing, you bounce your ray from the surface's normal and if it hits a "light source" then it's brighter (by the inverse square distance to the source). Maybe they explained the same way, except they used a different name?

Re: Scratchapixel 4.0, Learn Computer Graphics Programming

#38

Post by meindnoch »

jagged-chisel wrote: post #31
penteract wrote: post #23

Earlier quoted context omitted.

Until you can observe that light doesn't travel instantaneously, it would be consistent to believe that a beam leaves your eyes, bounces off a surface, and informs you (as though it were a limb, perhaps) when it hits a light source.

The more I think about it the weirder it gets. It’s day time, the sun is up, it’s a cloudless day. Ambient light is bouncing all over, including into a south facing window (i.e. no direct sunlight.) How does the Eye Light Emitter do its job in this case? Now, I don’t mean “this concept is impossible” because that’s clear. I’m genuinely curious how this would have been explained by someone at the time.

Vision rays emanate from your retina, get refracted by the lens, exit the pupil, go outside the window, get scattered in the air, and - some of them - end up hitting the sun.

Re: Scratchapixel 4.0, Learn Computer Graphics Programming

#39

Post by jagged-chisel »

Phrodo_00 wrote: post #37
jagged-chisel wrote: post #22

Earlier quoted context omitted.

> "...vision occurred through beams of light emitted from the eyes, interacting with the environment" How did they explain lanterns and torches in this theory?

A far as I know, in raytracing, you bounce your ray from the surface's normal and if it hits a "light source" then it's brighter (by the inverse square distance to the source). Maybe they explained the same way, except they used a different name?

I think this is plausible. I guess they thought unlimited ray bounces were a thing.
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