
An Introduction to Ray Tracing (1989) - walterbell
http://www.realtimerendering.com/blog/an-introduction-to-ray-tracing-is-now-free-for-download/
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bwidlar
[https://t.co/RHZKjvseIT](https://t.co/RHZKjvseIT)

"I've decided to make pdf's of my ray tracing books available at "pay what you
want". This can include zero, which I encourage for students and any other
cash-strapped people. 50% of gross proceeds will go to programming education
non-for-profits."

Peter Shirley

[https://twitter.com/Peter_shirley/status/984947257035243520](https://twitter.com/Peter_shirley/status/984947257035243520)

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seanalltogether
Something similar also popped up on the /r/programming subreddit today that I
found very easy to follow through

Understandable RayTracing in 256 lines of bare C++
[https://github.com/ssloy/tinyraytracer/wiki](https://github.com/ssloy/tinyraytracer/wiki)

[https://github.com/ssloy/tinyraytracer/blob/master/tinyraytr...](https://github.com/ssloy/tinyraytracer/blob/master/tinyraytracer.cpp)

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tpaschalis
Wow, this is a terrific repo, props to the creator! I'm gonna try and recreate
this in Golang as a learning exercise.

I think you could also submit it as a standalone post for more visibility. ;)

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mroche
This came up yesterday, you’ll see if it you go back a page or two, or use the
search.

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cowmix
Holy crap, I bought this book when it came out and lost it in a move long ago.
I guess if I live long enough all my favorite computer texts will be available
free at some point.

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cr0sh
Well that's funny.

Back around 1992 or so I picked up a copy of this book, in hardcover, from a
local bookstore (Bookstar - remember them?) - still in plastic wrap.

I was like 19 and naive. I paid something like $80.00 for it.

Opened it up - tried to understand it - the math was well beyond my pay grade.

Still is.

It's been sitting on my shelf every since. Probably the worst book purchase I
ever made; had it not been in plastic I could have at least leafed thru it to
see that I wouldn't understand it. At the time, $80.00 was a lot for me.

Live and learn, I guess!

:)

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jacquesm
In a nutshell, simplest form of raytracing: imagine a point where your eye
sits behind the screen, throw lines from this point into the screen hitting
each pixel dead center into the scene, check which objects you hit, how far
away from the origin point that happens and sort by depth. Take the nearest
one, render in color based on angle of incidence compared to lightsource.

That's the very simplest form of raytracing that you could do, then you can
add reflection and transparency and other niceties that lead to the splitting
of the rays and a summation at each hit.

This is actually reverse raytracing, forward raytracing starts from the
lightsource, doing it backwards is an optimization because a lot of the light
would end up hitting absorbing surfaces long before it would hit the plane of
projection.

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melling
A few additional ray tracing resources:

[https://github.com/melling/ComputerGraphics/blob/master/ray_...](https://github.com/melling/ComputerGraphics/blob/master/ray_tracing.org)

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ggambetta
Might I suggest [http://www.gabrielgambetta.com/computer-graphics-from-
scratc...](http://www.gabrielgambetta.com/computer-graphics-from-
scratch/raytracing.html) (shameless plug)?

~~~
ggambetta
And on the other end of the scale, [http://www.gabrielgambetta.com/tiny-
raytracer.html](http://www.gabrielgambetta.com/tiny-raytracer.html) (another
shameless plug)?

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Bjartr
I quite enjoyed Ray Tracing from the Ground Up when I was learning ray tracing
for the first time.

[http://www.raytracegroundup.com/](http://www.raytracegroundup.com/)

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dgoodell
The linked pdf copy has kinda mediocre quality. Google’s scanned copy looks a
lot better. I wonder if it would be possible to get google’s pdf to share
instead since there is legal permission?

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kyberias
Oh, awesome! This is the book I learned ray tracing from. The basic math is
still very relevant.

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ngcc_hk
Quite old. Latest 2014. Still relevant?

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wongarsu
The fundamentals of Ray Tracing are very simple and haven't changed. Most of
the advances in Ray Tracing are either simulating complicated materials (e.g.
skin, or perfect simulations of car paint) or speed optimizations advancing
the quest for real time Ray Tracing.

