Coding Challenge 145: 2D Raycasting

[@atrumluminarium]

Omg this video is so coherent and organised unlike the live stream. Your editor needs a raise Dan hahah

[@MattRose30000]

That's why I always wait for the edited versions, they are just so much nicer to watch.

[@taba1950]

@@MattRose30000 while true the live stream still have a unique entertaining value

[@LuisHansenNH]

Showing your code VS coding live. That's why I hate coding interviews. It's like they say: the worst part of parallel parking are the witnesses.

[@vintyprod]

@@taba1950 while(true)

[@MizhiBirb]

more like a RAYS

[@discreet_boson]

This man is an international treasure and should be protected at all costs

[@MSecYT]

6:59 "I didn't forget this time"... immediately forgets to add this to the dir.x, and dir.y

[@justiceforsethrichwwg1wga160]

I’ve been watching your channel for awhile now....you’ve gotten way better at your presenting! Really great content! Easily one of my favorite channels.

[@nehoymenoy3845]

It's awesome when a feature can be implemented for both visual and functional purposes.

[@dkkoala1]

The ray.cast method is already calculating the relative distance to each intersecting object in the form of "u", so an optimization would be to use it instead of the p5.vector.dist function. This is more efficient because p5.vector.dist uses euclidean distance, and therefore calculates square roots each time it is called, which is a heavy calculation. But great video as always!

[@TheCodingTrain]

Thanks for the feedback!

[@dkkoala1]

​@@TheCodingTrain No problem, i always love your videos because they remind me that coding can still be beautiful. Im a machine learning master student, so your project with the self driving car interests me very much, even though i am more of a supervised learning guy. Please feel free to contact me if you need some resources for how to approach the subject. In any case you should definitely check out Arthur Juliani's Medium article about Q-learning, it is a very good resource to reinforcement learning.

[@likeyou3317]

So smaller "u" means dist is smaller?

[@TheCodingTrain]

@@dkkoala1 Indeed, such a great reference!

[@dkkoala1]

@@TheCodingTrain Another thing that could maybe speed up your training is the concept of curriculum learning. It is done by starting out training with the simplest version of your problem and then as the AI gets better raise the difficulty of your training. An example could be starting with training the AI to drive in a straight line, and when it can do that then add a bend to the track. Multiple objective functions could also be useful, first prioritizing getting to the end of the by having the distance to the goal as your loss, and afterwards using the speed at which the AI can get there instead. In this way you first ensure a basic understanding of the task and then you can optimize it make the model better and faster at the task. Unity has a great blog for curriculum learning blogs.unity3d.com/2017/12/08/introducing-ml-agents-v0-2-curriculum-learning-new-environments-and-more/

[@TheFlamingWaldo]

I program in Python -- I used C++ back when I was in college, but it didn't sit well with me -- and I was inspired by this to try to program some raycasting *in* python, despite my limited experience with trigonometry. I tried my best to construct as many of the math-related functions as I could from scratch, which means I made my own function for finding magnitude, normalizing lines, for projecting lines out at a specific angle, etc etc. I was worried it was going to run awful, but it's actually pretty smooth! It was difficult for me, as I've never taken a trigonometry course and I actually managed to fail remedial math once, but something about wanting to accomplish something makes me learn more. I feel really happy with myself, even if I have what would probably have been easier if I had just used built-in library functions to do my work for me. Your work always inspires me, and this is the third project I've made based off of the suggestions in your videos, so thank you so much!

[@matiascollado9926]

How did you make the ray extend to infinity in one direction?

[@adammoore4359]

@@matiascollado9926 did you figure this out?

[@matiascollado9926]

@@adammoore4359 I did not extend it to infinity, rather I extended it far enough that the user never sees the end of the rays

[@rolandferguson1209]

I haven't been programming in a while and jumping back in to your tutorials I get to see how much comedy you've added! it's great to see you so expressive

[@cassioschneider922]

i've never coded anything. don't know why i watched the entire video. still, this is AWESOME thanks! cheers

[@TheCodingTrain]

You can start learning here! kzbin.info/aero/PLRqwX-V7Uu6Zy51Q-x9tMWIv9cueOFTFA

[@cassioschneider922]

@@TheCodingTrain Thanks for replying! i'll definitely try it out :D

[@cassioschneider922]

@@nerasure actually I watched the entire playlist with the starting tutorials! I made some really cool stuff, made 3d pong, moon phases shown in 3d, a few simple games and other simple stuff just to try out p5js and learn a little I would definitely recommend it, Daniel is an awesome teacher, always so positive and ready to a swerve questions!

[@kenan2386]

:)

[@aleksszukovskis2074]

sleep watching?

[@yourteacher4353]

So basically there are two kinds of people: 1) people and 2) people who brighten your day up. You Daniel is the king of kind 2.

[@DenerWitt]

I like the light like effect at the end. when math and programming become art. Pretty.

[@izangomez6806]

3:25 Code bullet will help you, sure

[@mariovelez578]

Tokyo drifting!!!

[@abdulalhazred5924]

NANI! Train Dorifto!

[@DamageMaximo]

I remembered of him!

[@batonator]

i love your enthusiasm, you make me wanna code more. I can't wait to get a PC

[@HellTriX]

The end result to this one was absolutely beautiful. I think its my favorite one yet. I also cannot wait to see some NNs applied to this!

[@wlockuz4467]

This video is simply amazing! I always used to think of Raycasting as this very complicated topic which requires a good understanding of Math but at not point did it feel like I didn't understand this video. I am blown away!

[@proxy1035]

2:34 when your parents ask you to do anything

[@masonhunter2748]

I would give a like but it’d overflow

[@soejrd24978]

That plan on this project is insane!! I"m so hyped!!

[@7cle]

Keeping this that simple, given the complexity of the subject is the mark of a rare gift Dan : intelligence! Thank you for sharing it with us. It is a pity so many are not fussed to share stupidity on social media though.

[@NinjarioPicmin]

Yay for Nicky Case. I love a lot of their work

[@squirrel1620]

When I was coding with unreal 2 and 3 engine, the Trace and FastTrace were used for ray tracing. It worked more or less the same, mathematics wise anyways. They pull more tricks to avoid multiplication or division because it saves time.

[@sushicook816]

This channel is a gold mine for researchers.

[@thegoodhen]

This really reminds me of SLAM (simultaneous localization and mapping) visualizations in robotics. You have a robot with a LIDAR scanner and it sees the environment in exactly this way, as it casts multiple laser rays.

[@ValleyOfWillows]

Making the boundaries into letters with the same color as the background and then having the lightsource just randomly go around the canvas would probably make a cool screensaver.

[@zelioz848]

Yo that is sick, i'm gonna learn how to change my desktop background to something like that and program it myself

[@CYXNIGHT]

I used to code on Gamemaker, and was transitioning to Unity, but I came across your channel and Java is now my favourite language. I was getting discouraged from coding as Gamemaker couldn't do what I wanted, but since your channel popped up in my recommended I have sinced been coding almost every day as I never cease to find something to code, I can't thank you enough. I love your channel and your vibrance, I hope you never stop these videos, and live-streams!

[@33KK]

He uses JavaScript

[@TheCodingTrain]

Thanks for this nice feedback!

[@nkheart4]

My first goal is to learn what you teach, but I also enjoy seeing your reactions when you start coding. I see myself in you, so I love your channel because I feel the same joy you get when coding graphics like this.

[@DodaGarcia]

That ending made me SO happy I can't even describe it

[@husseinshukre3828]

Great video helped me build openGl program that recolor the selected polygon

[@jcoco44]

This is the first time I've watched your videos, and frankly, I'm a bit disturbed by how excited you are. It's contagious...

[@julianirmer5854]

The only channel for which I activated notifications.

[@cidie1]

Thanks so much, I'm half watching for the subject and half watching because you are just so fun!

[@Apoorvpandey]

Coding train : " Making world a better place to live in "🌼🌼🌼

[@ivankorytko1964]

The best explanation of the work. Interesting, understandable, not boring and I was impressed that it is easy. I do not know JS, but the idea and logic is quit simple. Thanks for your videos.

[@brianbrooks4448]

Very interesting subject matter. Love the quirky presentation style. Sub added. I'm interested in using this type of algorithm, but converted to an electronic system using ultrasonic emitters and sensors. This video was good inspiration though, so thanks for that.

[@HoneyDustTheReal]

i'm just putting my idea here but i think it would be really cool and entertaining to combine the maze generator algorithm with the a* pathfinding algorithm to solve it and finally this one that could be implemented by redirecting the "light source" to the mouse cursor and be able to explore the maze (which would be all dark at first) and just seeing the light making it's way to the edges of the paths as we move along them, like some sort of dark exploration game

[@Mabeloid]

sounds like 2d scanner sombre

[@MagnaKay]

The enthusiasm is so contagious ahah. Good job!

[@Csc5csc5]

Bruh, that's a lot of energy before noon. Coffee or Red Bull?

[@elbowrustler]

Your enthusiasm got me excited as well. I'm sure it was worth a sub (:

[@catherinebernard3282]

Thanks to this I managed to get a version of this working in gamemaker (studio 2). Was a lot of fun.

[@bluepixelmusic9463]

finally a channel that doesnt expect me to be a master brain

[@Couchwurst]

Thank you for this awesome Coding Challenge! And for bringing up the reference to Nicky Case - his game and ideas are fantastic!

[@thebrickccentric3728]

2 cases that the line segment intersection check here forgets to consider (which become more apparent in the next video): -If the ray is parallel with the wall, but also directly in line with it, the intersection check here will return empty when it should return the closer of the 2 endpoints of the wall (and the distance to it) -If the particle/vehicle is sitting directly on a wall (or if a wall has the same start and endpoint / 0 length), then the intersection check should return the ray's origin point (0 distance) no matter what Great video though; this stuff is super useful

[@ai_zj]

And Dan said, "Let there be light," and there was light.

[@shaileshrana7165]

Light also diffuses around edges. Maybe that can be added.

[@Edd4324]

I love your sticker on your laptop says never forget the this dot and you forgot it in the first part of the code! Great Video as usual!

[@OrangeC7]

Wow! I've seen and been to basically everything he referenced at the start of the video. Does this mean I'm finally good at the internet!?

[@Apoorvpandey]

You're cool !

[@alfcnz]

Impressive! 🤯🤯🤯

[@MemoryPrimeMinister]

Coding a line would send me off the wall. Then here you are making ray casts

[@imvickykumar999]

You are my inspiration 🤘🤘

[@mihaisolomon2893]

I did something like this 1 month ago, but my code wasn't so explicit, thank you for the explanation

[@sonik382]

I am trying to code the AI car as well...awesome you suggested that! Can't wait for the next challenge! Greetings from Italy!

[@run4thewin357]

This is the most interesting video i saw this year

[@silvertakana3932]

15:08 Him: Now, it’s time for me to get YOU! Me: *running out of my room*

[@therealstillie]

That was unbelievably enjoyable to watch!!!! Thank you

[@8bit_pineapple]

♫When A Grid's Misaligned With Another Behind That's a Moiré♫

[@masonhunter2748]

You stole it

[@8bit_pineapple]

@@masonhunter2748 Yea. Credits to xkcd comics, that everyone here should read ;)

[@masonhunter2748]

8bitpineapple what’s the number

[@-Burb]

@@masonhunter2748 1814

[@abazur7742]

now after this video i can tell that you are a genius

[@medhavimonish41]

wow , you never fail to amaze

[@garychap8384]

More efficiently, when trying to identify the whole area "visible" from a point ... For all obstacle endpoints, take their angle. Sorting the endpoints by these angles gives you a clockwise (or anticlockwise) list of points. Now it's easy to evaluate each point in turn, working around the circle to construct a convex region of points. You can then gradient fill that region, or use the region to apply dynamic lighting/shadows. You can even do some fairly complex stuff with this region/origin ... particularly if your 2D tiles have an extra map for a simplified 'normal' and 'height'. The height lets you suspend lighting (for some distance) along the ray, giving you tiles that cast shadows onto tiles, to cast composite shadows on floors. Orientation and Slope values per pixel let you modulate how a dynamic light affects the base texture. But, at its very simplest, you can just use a very weak alpha with a circular gradient to give a very subtle effect which, although it's not accurate, is subtle enough that people don't notice. You can have lots of fun with these regions.

[@RedMasterJV]

LMAO that "this dot" tune is great

[@scatheroy]

Just awesome. Great video. Thanks, man.

[@andrewweller5119]

Great, thanks fo rthis. i re wrote it all to work in Game Maker Studio and have learned soo much.

[@My-video123]

At first I thought you are very strange guy. After several your videos I just realized it’s a gold material to be taught and implemented. Thank you mate

[@mr.budders8740]

My man, I want to give you the highest honor I can bestow for teaching me in 20 minutes (only the first portion of video) how to detect ray intersection when everywere else says that you gotta to a bunch of tan() cos() and sin() functions with some more advanced trigonometry within and hour. A subscribe BTW I litterally spent 4+ hours trying the other method and it never worked

[@homelikebrick42]

BTW that is actually what p5 is doing for you inside p5.Vector

[@FazpyDev]

This video is so useful, I'll for sure have a look at it!

[@WzzupDaAwsome]

What if you made the light that hits the walls reflect back at whatever angle it hit the wall? I've seen videos of rooms where there is a single point where light can't reflect to, it would be cool to test that out with this program.

[@dalegriffiths3628]

Fantastic - can't wait for the self driving vehicle you mentioned you'd like to do with this!

[@massimogiardina9138]

You helped me so much with this. How could I ever thank you?

[@AB-hr4qg]

Programmers: I can create nearly anything! I have incredible power! Except that one thing... *glances fearfully at "this."* ...It scares me...

[@itoverview-awesomeandroida1492]

Congrats on 1 million! :)

[@anotherdimension97]

Grandioso, saludos desde Perú.

[@MrNosugarcoating]

Wow that looks so cool

[@alexmattheis]

Very good explanation and coding.

[@TSPxEclipse]

Personally I would have loved for there to be a segment added into the code for reflection/refraction, but with a simple ray vs. boundary setup on a 2D plane that would have been complete overkill.

[@arsnakehert]

"This comes from 15 years of programming in Java" Oh, I can see the Vietnam flashbacks in his eyes

[@Jeff-Vader_head_of_catering]

Very cool! My brain melted about 1/4 of the way into the video, but, cool.

[@elendil4543]

This guy can make whole game engine with processing

[@SomeOrangeCat]

If my computer sciences professor used a train whistle, I would never have dropped out of college.

I've been a subscriber for a while but I'm not used to watch a full video. That one caught me and I was able to follow easily your train of thought even tho I don't know those libraries. Amazing work. Programming should be exciting as you are showing!

[@AlejandroCastilloRapper]

AMAZING. BOOKMARKED

[@xiija]

Dan the Man is the BOSS! ♥

[@Damian_Stefann]

Dude i am making videogame and i needed this! Thanks :)

[@wumbl3]

24:23 first sighting of the covid-19 virus. May 8th 2019.

[@hungrypasta]

colourised

[@krccmsitp2884]

I really like your step-by-step explanations and approach to solving problems. What looked too complicated at first becomes gradually more comprehensible, and finally you think to yourself, "what, it's that simple?".

[@itay1213141]

Great video, i love these so much 😁

[@RhoTrepaan]

it looks very pretty! :D (and very informative, too)

[@nicolasmarques7460]

Amazing thanks for share this content!

[@OrangeC7]

You should check out CodeParade's videos on ray marching as well. There are a lot of cool things you can do with the technique! :D

[@DIProgan]

Cave searching game where items or monsters appear only when rays hit it. Limited angle of rays for the flashlight effect controlled by mouse while the character is controlled by keyboard

[@OrangeDied]

The funny thing about this guy is he sounds like me after doing something for 4 hours talking to myself, like "So now I have to do this, and it should... do the thing"

[@moonythm]

Already watched the stream :)

[@lenrik_]

Me too!

[@JanBebendorf]

But you probably haven't seen this intro/outro, it took him an hour to record :D

[@TheCodingTrain]

Haha, so true. . . .

[@omaislindodesantos]

great video really thank for doing it.

[@ratdn]

damn you did all this in less than an hour and it took me like 20 hours to recreate this in python using tkinter

[@Briggoes]

always wanted to learn this! thanks!

[@photoelectron]

thanks for sharing, that was pretty neat !

[@frankie_goestohollywood]

Brilliant video!!!! Thank you :-)

[@avi12]

Dan, from Chrome 74, when initializing values in a certain class - you no longer need the constructor. Just initialize them Unless, of course, your constructor receives parameters

[@TheCodingTrain]

Thanks for the tip!

[@Xeronimo74]

awesome tutorial!

[@artistpw]

This would make a great night light on a screen.

[@jonmichaelgalindo]

I just tried doing this last week, and I also arbitrarily picked cast(). :-) Although I first intersected the ray with a polygon's bounding-box (polygons had translation/rotation/scale), then transformed the ray into the polygon's local space, then calculated the intersect depth (if any), then transformed that depth back out to the ray's space. That way I didn't have to convert all the polygons' vertices to global space, since I only need the ray's collision point for drawing.

[@jonmichaelgalindo]

Also, it looks like you're using p5 for vector stuff, but I was just using JS.

[@notgate2624]

I would love a video on ray tracing! Great video!

[@t.m.h1721]

Your video inspires me a lot