This is the best shader high level intro I've ever seen. So many introductions are either not succint or focus too much on something too specific for a intro.
Kudos for drawing attention to independent and parallel execution of shader code, as someone who teaches this stuff in computer graphics class, I want to stress that also. That answers many questions from people coming from "regular" CPU programming and adjusting to this, like "why can't I pass a variable to next pixel?" or "why's there no random function?", etc. Shaders are (mostly) meant to be fire-and-forget, no waiting around, no syncing with each other, otherwise the performance would crumble. This way, you can have massive parallelism, litereally thousands of real hardware threads running simultaneously, without worrying about it.
Also note the difference between a real-time shading language (like GLSL) versus one for non-real-time use (e.g. OpenShadingLanguage, OSL). The latter does indeed have a random function, only it calls it “noise”. Another fun concept in OSL is that of a “material closure”. This is how you define the characteristics of the material independent of the actual lighting. For example, you have built-in closure functions for microfacet, refraction etc, which you can combine in your own arithmetic expressions, and leave it to the renderer to work out the actual lighting at each pixel.
You have an amazing way with words! Easy, EASY to align my thought process with what you're saying. I specifically thought the word "Bucket" and you said it less than 2 seconds later.
It's best to avoid if conditions in shaders. While modern GPUs are a lot better at handling this, they don't have an actual ALU circuitry for every cores/SMs. So basically, the GPU renders BOTH conditions, and then at the end decide which one to pick. So, for every if condition, you render twice... sometimes you don't have a choice to have an if condition, but many times they are other ways to code things to avoid them, and this is where experience comes into play. The good news, is that the web is filled with examples, and there is a lot to learn from.
I think it's important to distinguish between the two kinds of shaders. Namely the vertex and fragment. Where fragment shaders are done for every pixel (therefore also known as a pixel shader), vertex shaders are done on every vertex. The order of the shaders are also key; Fragment shaders are applied _after_ Vertex shaders. So in this video the pixel shading (colors changing) are fragment shaders, whereas cell shading (toon shading) uses vertex shading, since they have to extrude from the model in order to make the outline around the models. The color of the outline are then applied by the fragment shader.
ui_wizard Wind waker don't have outline, borderland do it as a (fragment) post process, and okami just use a reverse shell since ps2 don't have shader... It's not always vertex like afro samurai, which push the second pass vertex along the normal by flattening it in the view direction.
ui_wizard the technique you mentioned uses the vertex shader to upscale a pitch black copy of the model that stays right behind the normally drawn one like a bigger shadow. But this was used mostly in earlier games because it was cheap in processing power. The newer installments use one or a combination of the 2 techniques: - Interpolate normals from vertex shader and set any pixel with angle over a certain threshold to pitch black using fragment shader - Edge detect using sobel/laplace/whatever algorithm you prefer and overlay as a post processing effect on fragment shader. I also remember someone mentioning in forums a technique where a depth-map (z values) of the screen was edge-detected and overlayed to the render to make the lines.
I would like to say that fragment shaders can be done multiple times per pixel in the cases where there’s transparency (so the same pixel can have multiple geometric fragments it needs to do processing on) or if whatever reason your GPU decides to do depth tests after the fragment shader has finished running instead of directly after rasterization. Thus, making the word ‘fragment’ in fragment shader a more reasonable and appropriate naming than pixel shader IMO
Wow. Finally I got an understanding what is shaders. It's a piece of code, in which you put every pixel of an object, related to this shader. It makes some calculations, depends on what nodes you put inside. Then it returns a color value for these pixels, to render it on screen.
Very nice intro into a very complex theme. Even when it comes shading of objects in a 3d space with multiple light sources and various calculation techniques. I'm looking forward to the next part - thumps up!
Thanks for precisely pointing out pixel shader is a function applied to all pixels which takes position as the argument and does not depend on the adjacent pixels. Are all the other shaders also depened only on the postion and does not care about the values of other entities ?
I just discovered your channel, and I’m so happy RUclips recommended it to me. I’m a design student in college and a lot of things that are interesting to me are jam packed into this video. I also love how you take time to explain various concepts in detail
Ive always liked lighting in games as far as graphics are concerned, so its interesting to learn whats actually happening. Im looking forwards to the code :)
I'm a very young (10 years old), game developer using unity. I really enjoy your creative computer content that helps me (even though you're not using unity)when I have a question. I just wish you can upload again. :-)
I always wish Photoshop had a shader language like Maya Hypershader except for 2D layers, that would be so powerful compared to their fixed blending options.
This video is more about what is a pixel shader (or fragment shader). They are the most common (I guess), but I think you should've told that there are more types of shaders than just that just to prevent confusion.
Hi, I have Linux and somehow the Intel open source driver is not giving me the option to adjust contrast and my colours looks washed, can I use a shader with my existing X11 compositor to get more contrast?
Hey you are really good at explaining things that even us non programmer understand a bit 👏👏👏👏 and can I ask can you make something about rigid bodies ?
That actually makes a lot of sense. Huh. You did a good job explaining it so far. I want to see what you have to say in your future videos on the topic. :p
Madam, you really need to update that thumbnail. I find the thumbnail as an old, Indian tutorial-style boring video. But the video itself is sooo great, it answers all my questions. I recommend you to use some thumbnail with more colour, I think a colourful thumbnail will make it looks better and eye-catching also OMG this video is so great, its a masterpiece :D Thank you sooo much, it's really helpful to me and anyone else
This is great I would be interested in knowing the differences and intro into HLSL and GLSL and how to utilize a pbr shading model based on brdf lighting (in code / the techniques not UE4 Material editor).
how could I detect specified object rather than colors? for example I want to apply water shaders, I must choose blue color bcoz the water is blue, but I won't let shaders affected to another blue color.
0:30 No, those are “pixel shaders” or “fragment shaders”. There are other kinds of shaders, e.g. ones executed for every vertex of the geometry (“vertex shaders”), also “compute shaders” etc.
Thank you very much for this video, it was pretty useful for understanding shaders. I will work on Spanish subtitles for this so I can recommend this video even to people who are not good at English :D
For me i make the background scene with photorealistic rendering..... the characters with npr and special effects in 2d drawings.... and its very awsome
Oliver Wright I know I'm a bit late, but what does this do? The operators specifically :) I've never written/ seen this coding language before but it looks quite interesting!
Dear. HappieCat, I was wondering if you understand what to do after an indie developer has a game or a demo of a game completed. I feel like it's more than just putting up a file on a digital distribution site like Steam besides spreading the word.
It's just code executed in parallel! With compute shaders you can even choose how many different processes you want to compute at once instead of doing it on a per pixel basis
This is the best shader high level intro I've ever seen. So many introductions are either not succint or focus too much on something too specific for a intro.
wow
wr
Kudos for drawing attention to independent and parallel execution of shader code, as someone who teaches this stuff in computer graphics class, I want to stress that also. That answers many questions from people coming from "regular" CPU programming and adjusting to this, like "why can't I pass a variable to next pixel?" or "why's there no random function?", etc. Shaders are (mostly) meant to be fire-and-forget, no waiting around, no syncing with each other, otherwise the performance would crumble. This way, you can have massive parallelism, litereally thousands of real hardware threads running simultaneously, without worrying about it.
Also note the difference between a real-time shading language (like GLSL) versus one for non-real-time use (e.g. OpenShadingLanguage, OSL). The latter does indeed have a random function, only it calls it “noise”.
Another fun concept in OSL is that of a “material closure”. This is how you define the characteristics of the material independent of the actual lighting. For example, you have built-in closure functions for microfacet, refraction etc, which you can combine in your own arithmetic expressions, and leave it to the renderer to work out the actual lighting at each pixel.
43 people are from Australia and clicked thumbs up, but it came out upside down
Where were you all this time?
I've been looking everywhere
for knowledge about shade
and you've shown me the light
i dont know how but you nailed the timing of publishing this video. Just in time. Like some superhero.
You have an amazing way with words! Easy, EASY to align my thought process with what you're saying. I specifically thought the word "Bucket" and you said it less than 2 seconds later.
For the checkerboard code, you can just do:
If( x+y%2==0) {
Black();
}else{
white();
}
At 2:04 You don't need all those conditions.
Tom l
Assignments do it without If because GPU don't like, hint exploit the modulo, an add and a mul, remember what multiplying by zero do.
col.rgb = (x + y) % 2; 🐱
Ava Skoog try (x^y)&1, since you are more advanced
Oh, that's so clever! Because the last bit keeps alternating between 0 and 1. Really cool.
It's best to avoid if conditions in shaders. While modern GPUs are a lot better at handling this, they don't have an actual ALU circuitry for every cores/SMs. So basically, the GPU renders BOTH conditions, and then at the end decide which one to pick. So, for every if condition, you render twice... sometimes you don't have a choice to have an if condition, but many times they are other ways to code things to avoid them, and this is where experience comes into play. The good news, is that the web is filled with examples, and there is a lot to learn from.
nice to see people willing to sponsor this channel
I think it's important to distinguish between the two kinds of shaders. Namely the vertex and fragment. Where fragment shaders are done for every pixel (therefore also known as a pixel shader), vertex shaders are done on every vertex. The order of the shaders are also key; Fragment shaders are applied _after_ Vertex shaders.
So in this video the pixel shading (colors changing) are fragment shaders, whereas cell shading (toon shading) uses vertex shading, since they have to extrude from the model in order to make the outline around the models. The color of the outline are then applied by the fragment shader.
ui_wizard
Wind waker don't have outline, borderland do it as a (fragment) post process, and okami just use a reverse shell since ps2 don't have shader... It's not always vertex like afro samurai, which push the second pass vertex along the normal by flattening it in the view direction.
ui_wizard the technique you mentioned uses the vertex shader to upscale a pitch black copy of the model that stays right behind the normally drawn one like a bigger shadow.
But this was used mostly in earlier games because it was cheap in processing power.
The newer installments use one or a combination of the 2 techniques:
- Interpolate normals from vertex shader and set any pixel with angle over a certain threshold to pitch black using fragment shader
- Edge detect using sobel/laplace/whatever algorithm you prefer and overlay as a post processing effect on fragment shader.
I also remember someone mentioning in forums a technique where a depth-map (z values) of the screen was edge-detected and overlayed to the render to make the lines.
There are more than two kinds.
Well, there are more than that, but fragment and vertex shaders are often used than those aren't mentioned.
I would like to say that fragment shaders can be done multiple times per pixel in the cases where there’s transparency (so the same pixel can have multiple geometric fragments it needs to do processing on) or if whatever reason your GPU decides to do depth tests after the fragment shader has finished running instead of directly after rasterization. Thus, making the word ‘fragment’ in fragment shader a more reasonable and appropriate naming than pixel shader IMO
Wow. Finally I got an understanding what is shaders.
It's a piece of code, in which you put every pixel of an object, related to this shader. It makes some calculations, depends on what nodes you put inside. Then it returns a color value for these pixels, to render it on screen.
_doing Computer Graphics assignment_
Me: The f*** is a shader?
TheHappyCat: _this video_
Holy shit, literally the same thing happened to me. Just started a graphics course and by the time I hit shaders this video came out.
If you want to know 100% what is a SHATER. just go to the "NVIDIA" CHANNEL THEY have a better video of 2 hour explanation how a shator work.
Francisco: Would you mind posting a link to the video?
wtf is a shater/shator tho? xD
When you go through a whole Computer Graphics class without learning about shaders because your professor uses the old version of openGL . . .
"Have a happy day wherever you are"
What a sweet way to sign off on a video hahaha.
YOU have a happy day
Very nice intro into a very complex theme. Even when it comes shading of objects in a 3d space with multiple light sources and various calculation techniques.
I'm looking forward to the next part - thumps up!
Thanks for precisely pointing out pixel shader is a function applied to all pixels which takes position as the argument and does not depend on the adjacent pixels.
Are all the other shaders also depened only on the postion and does not care about the values of other entities ?
Seeing your videos on things like this make me really want to get up and experiment! Thanks for another awesome video!
Love your videos. You sum up even complex subjects so nicely. Not so nerdy and not so shallow.
I just discovered your channel, and I’m so happy RUclips recommended it to me. I’m a design student in college and a lot of things that are interesting to me are jam packed into this video. I also love how you take time to explain various concepts in detail
I wish that this video existed when I first started learning shaders, very good high level introduction and explanation.
Ive always liked lighting in games as far as graphics are concerned, so its interesting to learn whats actually happening. Im looking forwards to the code :)
Visual node based shader editors are available and they make the learning process a lot more user friendly!
That was actually helpful. Now I finally understand what shaders are 👏🔥
Wow I've just discovered your channel. Your explanation is so neat and easy to understand.
Never worked with shaders before, but this was a fantastic video. I learned a lot! Subscribed.
Your videos are always so enlightening. You do a great job of explaining stuff that might otherwise be very difficult to understand.
Stellar explanation! Thanks a lot. 💜
I'm a very young (10 years old), game developer using unity. I really enjoy your creative computer content that helps me (even though you're not using unity)when I have a question. I just wish you can upload again. :-)
For a long time I had in the back of my mind just what the heck a "shader"was. Now I have some grasp of it, thank you.
As someone that knows nothing about shaders, this was incredibly easy to understand. Thanks for this!
I always wish Photoshop had a shader language like Maya Hypershader except for 2D layers, that would be so powerful compared to their fixed blending options.
I love your intellectual thought process
u falling in love too, Mr. Ronald57?
Loved it, please make more video about shaders, lighting and techniques! Thanks
Another great channel, never knew Game Dev RUclips has such great content, better late then never!
This video is more about what is a pixel shader (or fragment shader). They are the most common (I guess), but I think you should've told that there are more types of shaders than just that just to prevent confusion.
Too many games are definitely using the phong model cuz in a lot of games, things are weirdly too shiny.
Thank you so much! This had me exited for my next laboratory for the computer graphics course which happens to be about shaders :D
Hi,
I have Linux and somehow the Intel open source driver is not giving me the option to adjust contrast and my colours looks washed, can I use a shader with my existing X11 compositor to get more contrast?
Glad to watch this.
this was an awesome explanation
Awesome. Please more videos about basics like this.
I know im late to this video but I would like to see how refraction shaders work! plz!
Hey you are really good at explaining things that even us non programmer understand a bit 👏👏👏👏 and can I ask can you make something about rigid bodies ?
Thanks, your voice is so good
Great Video and topic explanation 🙌🏼🔥🔥🔥⚡
That actually makes a lot of sense. Huh.
You did a good job explaining it so far. I want to see what you have to say in your future videos on the topic. :p
doesnt ddx ddy gives you acess to the previous pixels? color in frag and vertex height in vert
This is the best ever shader video!
Madam, you really need to update that thumbnail. I find the thumbnail as an old, Indian tutorial-style boring video. But the video itself is sooo great, it answers all my questions.
I recommend you to use some thumbnail with more colour, I think a colourful thumbnail will make it looks better and eye-catching
also OMG this video is so great, its a masterpiece :D
Thank you sooo much, it's really helpful to me and anyone else
This is great I would be interested in knowing the differences and intro into HLSL and GLSL and how to utilize a pbr shading model based on brdf lighting (in code / the techniques not UE4 Material editor).
how could I detect specified object rather than colors? for example I want to apply water shaders, I must choose blue color bcoz the water is blue, but I won't let shaders affected to another blue color.
Damn, I'm a CG artist, and I couldn't have said it better myself!
Excellent, descriptive and concise introduction! Have a sub! :)
That's way giving instruction to the gpu (Shaders) provide less performance as compared to the game default graphics.
Can you please please explain more how Swift Shader the software works and why it works so well?
I am so impressed by all of your videos! your have become my new my favorite! :)
This was a phenomenal explanation. It's a shame you didn't continue down this path, of making educational content.
She would have made a killer course on computer graphics
wow, just week ago started to learn shaders, and this video appears!!!
waiting for another video!!!
0:30 No, those are “pixel shaders” or “fragment shaders”. There are other kinds of shaders, e.g. ones executed for every vertex of the geometry (“vertex shaders”), also “compute shaders” etc.
Great explanation!
yay, another educational video! Looking forward to the next one :)
Thank you very much for this video, it was pretty useful for understanding shaders. I will work on Spanish subtitles for this so I can recommend this video even to people who are not good at English :D
Fantastic tutorial :)
For me i make the background scene with photorealistic rendering..... the characters with npr and special effects in 2d drawings.... and its very awsome
SUPER HELPFUL
for the checker board pattern you could use, (x + y) % 2
Perhaps even faster: (x ^ y) & 1
Oliver Wright I know I'm a bit late, but what does this do? The operators specifically :) I've never written/ seen this coding language before but it looks quite interesting!
@@VirtualTurtleGames x XOR y AND 1
i am from india i fell in love with u ..seeing ur IT cs knowledge ..do i deserve u
Perv from India
Still an amazing video in 2024
Now I really want to get into graphics programming :)
The future asks, "Did you?"
@@man_vs_life Tbh no, but only cuz I'm focused on Data Analytics projects since that's my main focus. Obvious ones looking into COVID-19 atm
Very interesting !
@0:26 looks like the photo from Kojima productions at Siggraph showing their decima engine. They demonstrate something similar to this.
I miss this channel
Awesome video! I don't think it could be explained in a simpler way...
Thank you, this was very informative for a newbie to shaders!
Learning shaders is my next things!
Ooooh Now I understand why there was a character called "Phong" in the CGI cartoon, Reboot!
So what different between shader and color grading
Well done!
What are your favorite shaders in games? and why.
Thanks
I think is what curves and filters is in photoshop
Best shader intro I've seen for noobs yet!!! Very helpful and thank you for simplifying the concept so we can understand the basics
so can shaders be summerized as "object surface type/properties"?
Dear. HappieCat, I was wondering if you understand what to do after an indie developer has a game or a demo of a game completed. I feel like it's more than just putting up a file on a digital distribution site like Steam besides spreading the word.
thanks! very nice explanation.
Excellent introduction and examples, thank you. :)
thanks a lot doc
I’ve been coding for 40 years and I swear, shaders make almost no sense to me. Still, this video is getting me closer to understanding. Thanks.
It's just code executed in parallel!
With compute shaders you can even choose how many different processes you want to compute at once instead of doing it on a per pixel basis
Takes a bit to click for anyone. So hard after getting so used to sequential coding.
@4:09 "there is a link in the description", I see what you did there
love your videos!!
good introduction. very good even
Thank you! Thank you! Thank you! I LOVE your videos. They are super helpful!
That Okami reference made me happy :3
So, shader is like image filter?
Great to see new video :D and Verry interesting :)
Thanks teacher
Thank you!
do you know a software that i can use to create clip (video) from open source shaders? thx
But how do you tell your gpu to add borders around your 3d models if it only has pixel information?
just excellent
Would this shadertoy work for a full feature film color correction?
Where is pt2
Amazing, thank you!