Various problems - noob in distress

Hello, I’m so dissatisfied with cycles rendering of glass I decided to go to compositing, but I’ve never done it befote.
This is what I came up with:


But it’s not working.
In the glass material page there’s a message “No material node selected”, but it doesn’t tell me where to go to select one.
I have Use Nodes checked.
Gets worse: I have no idea what a “material node” is. I looked at other threads by people discussing glass compositing, and I saw all kinds of nodes I don’t seem to have, including a “Material Output”.
I seem to have only one “Output” node type, and it takes color and alpha inputs.
I saw a Fresnel node type… I compute fresnel myself, in the nodes above.
I also saw nodes having reflection rays and whatnot.
My version of Blender is 2.76, as later versions don’t run on XP, which I’m stuck with due to poverty.
Also my PC has no internet; using my phone for internet, so if there’s updates to install for compositing I have to get them as a file.
Note in the nodes sbove, I computed the reflection vector and then used it to fetch stars from a sky texture. I don’t know if this is correct or the “vector” input is supposed to be a UV vector…

Every Material needs a Shader. A Shader is the thing that calculates the color og a ray/pixel of an object based on the shader inputs. The output of the shader is than plugged into the material node. Otherwise the object will just be black. That what you are doing here (creating a material) is NOT called compositing. It is called shading. What exactly is your problem with the way cycles renders glass? If you set up the nodes correctlyy for a glass shader it should look pretty good. Not using the Fresnel nide and calculating is a bad idea. I think tt will be a bit slower, because the Fresnel node is optimized and your node setup can’t be easily optimized automatically. If it is somehow possible (transfer to USB Stick and use a Laptop/Pc with internet) it would be great if you could share your blend file with us (https://blend-exchange.giantcowfilms.com/).

It looks to me as though you have created a material for Blender Internal and then switched to Cycles.

@JohnMalcolm1970
Okay, I thought “cycles” was the name of the blender internal. I guess I’m using blender internal, period.

@ Patrick
I guess I never touched Cyckes.
The fresnel factor in blender internal is backwards. At shallow angles it reflects LESS than reflections close to the normal. And the whole setup is incomprehensible, like having a slider for how much fresnel to blend, when fresnel IS a blend. Metals and dielectrics should have separate setups; it makes no sense to mix these totally different families of materials the way the materials interface does. Metallic reflection has color, but does not change with angle. Dielectric reflection changes with angle but has no color; always white, no matter what the diffuse color is. Blender’s materials interface is a huge panel of bells and whistles to allow you to create a billion impossible materials for every useful one. Anyways, I’m ranting. I had a look at that file exchange site, and they are not satisfied wit my saying I agree to their legalese; they demand that I actually read it, and if I do I know I won’t agree. Besides, it asked me for the url to my question, and I copied it there, but it didn’t like it. Too much trouble. I’ll see if I can find some other upload place.

In the meantime, have a look at my glass windows with NO fresnel… look ridiculous.

Sorry, youtube says tha video will be published by midnight tonight Saturday. Trying to access it before the scheduled time works for me, the uploader, just so I remain in the dark about it, but results in a misleading and unhelpful error message for anyone else, about the video being private…
I just uploaded another clip which as it turns out will also go public by midnight tonight.

Cycles rendering of glass is the way glass would look in real life. What is your problem with it?

I already retracted that. I thought blender’s internal renderer’s name was “cycles”. I was using blender internal. I wouldn’t even know how to use cycles.

I’m still struggling with this. Why do I get this message “No materian node selected”? Where-T-F am I supposed to select “the material node”?

By the way, I’m starting to understand some things…
Even as I write I just discovered the buttons that switch between material, compositing and texture node graphs… I was computing fresnel and outputting to … a material!!! No wonder…

OMG … Spent about 2 hours creating a compositing thing this time. Still not sure where or how it plugs in. Hit F12 to try it…
Blender quit.
Recover auto-save has none of the node work I did. Heck, there’s hours of mesh work from before the nodes work also lost… Are there any stats on suicides among Blender users? Anyways, what I was TRYING to do, from the start, was to design my own FRAGMENT SHADER using nodes. You see, I worked for about 2 years writing GLSL code. So I was looking for a view vector, a light vector and a normal, but all I see here is a normal. Finally it clicked on me this compositing stuff is in view space. Am I getting this right?

https://pasteall.org/blend/
is a place that seems to be used a lot around here.

Ah, this site is better. Here it is:
https://pasteall.org/blend/adeff92de32b4f89a0819ec2413b98a8
And te clips I uploaded tu youtube now work:



All the textures used are packed in the blend file.
I have a new problem, tho. In the materials interface, the distance of reflections is hard-limited to 10 km. I don’t see why; all my cameras I was able to set the depth to 500 km no problem. Why is reflected light discriminated against?

UPDATE:
Downloaded a tool to convert cylindrical projections to cubemaps, appropriately named “Cubemap”.
But I was looking for where to plug in a cubemap in Blender, and all I found was a reference to there being “cubemap objects”, but could not find where to go to instance such a thing.
Finally decided to try Cycles, and it was already installed; I just had to select it with a button atop of the screen. I had never noticed those buttons and things up there…
But so now all I get in renders is the AO.

Things are looking up. Starting to get realistic looking materials, in Cycles, at least from what I see in the material preview window. But when it comes to actual renders, no lights except the AO.
Is there one typical thing newbies like me often miss about lights in Cycles?

Another question I have is about the environment map/background. I’m sure someone will say “these are not the same thing”; in my mind they are because when I was involved with the Vegastrike engine, many years ago, I pointed out the redundancy, and a few weeks later we switched to cubemaps AND unified background and environment functions. Maybe Cycles does it already; maybe not; I don’t know Cycles much yet. We also introduced LOD control in the shader, so that rougher materials can show blurry environment mapping, by fetching from deeper in the cubemap LOD. The results looked raytraced… I forgot this IS a ray-tracer.
Anyways, the questilon is where do I plug in a cubemap?

@JohnMalcolm1970 JohnMalcolm
@Patrick
@a59303
@watercycles
Trying to learn cycles as fast as possible, since what I’m trying to do is time sensitive (an in-space refueling technique proposal for SpaceX, if you must know), so please help me save time; I don’t have months to read the full manual and watch dozens of tutorials.
I got a matrial node for planet Earth, mostly working.

Preview

I’m using texture UV offsets to a) simulate Earth’s rotation, b) to fake clouds layer dynamics by making it drift in longitude relative to the diffuse mapping, and c) to fake the cloud’s shadows on the ground, though they don’t yet track the sun vector.
(Before you ask why don’t I rotate the planet, good question!, because I needed to use UV shifts to simulate the clouds drifting AND their shadows shifted away from the Sun, anyways, so might as well use the UV shift trick for everything. And if your next question is why not use a second sphere for the cloud layer, that’s because I tried that, in years past, and it looks terrible; PLUS it adds an awful lot of geometry to the scene.)
The whole node graph is a bit too big to show or dicuss…

…but the area of interest relating to my problem is the bunch of nodes at top left.
Have a look at them first:

Before I even describe it, two questions:

QUESTION 1:
Why do Normalize nodes have 2 vector inputs? In my book, " normalize" means making a vector unit length. What’s the second vector for?
QUESTION 2:
How do I get the view and sunlight vectors? The Object input node has a location output, but it doesn’t have an object selector, so I can’t get the Sun’s location. Then there’s a mysterious Light Path node that has a bunch of outputs prefixed with “ls”, but they are not vector outputs…

Presently my lights are not working in renders, so all my testing is preview window based. Which brings me to another question I’ve already asked several times:

QUESTION 3: How do I get lights to work in Cycles?

So I figured, first step in faking shadows is to compute cross product of view and normal, then dot the result with Earth’s North vector. Multiply that by an arbitrary small number of degrees angle, and use this as longitude UV shift for cloud shadows. Not scientific, but it should work.
But it doesn’t.
So I introduced a few nodes temporarily to see if my manually entered Sun vector was right. Those are the nodes highlighted bottom right. They basically show a pink spot in the direction sunlight’s coming from. Surprise surprise! It’s coming from the South, melting Antarctica!!!
But this makes no sense, as my North vector is (-1,0,0) and my Sun’s vector has X at zero.
So I suspected that second vector input of the Normalize nodes, but I tried initializing them to different values and it made no difference!

QUESTION 4:
WTF…?

QUESTION 5:
Is there a way to give animation variable values to material node inputs? If so, how?

QUESTION 6:
I forgot what it was…

Q1: Only the first input is used. It doesn’t matter what you put in the second input.
Q2: Thats a bit trickier because in a Shader/Material you have only access to the data from the current object. In your case the earth. To get position and rotation values of another object in your material you need to use drivers. Just use 3 value nodes (x, y and z) and create a driver for every input that is driven by the x, y and z position of your sun lamp. Here is a good tutorial for using drivers: https://www.youtube.com/watch?v=BJJJpWcxp0o
Q3: Here is a basic lightning tutorial: https://www.youtube.com/watch?v=gTMORaEygRE. If you have any concrete problems with lightning you could share the *.blend file with the earth.
Q5: Not sure what you mean. Yes, you can animate / keyframe node inputs. Just set a value, got to the desired keyframe, hover your mouse over the value and hit “I” this will (I)nsert a keyframe.

But I would create a second sphere for the clouds. This is more realistic and should look better. Than you dont have the problem with faking shadows, because Cycles will create realistic shaders based on your lightning. And one sphere more isn’t that much more geometry.

If you want a really realistic atmosphere, have a look at this great atmosphere shader. It will take for ever to render but it looks so nice.

Million thanks, Patrick. That’s a huge help for me. The question I’d forgot about is about cubemaps; but I just saw in texture nodes there’s Environment and Sky textures.
Environment supports mirror ball and equirectangular, by which I think they meant “equiangular”. The stars texture i downloaded from NASA is equiangular, so half my problem is solved without a cubemap.
The other half is the sky, but I have a theory how it works… that’s a Compositing node rather than a material node, right? Just have the environment texture output mixed with the scene in proportion to the written alpha?
Well, I just did that but see no stars yet.
I’ll check out those tutorials. Thanks again.

Starting to get some results.
I have two complaints, though; but it’s probably my fault.
Rendering time: 640 by 360 is taking almost an hour. Keep in mind my PC is very old, dual core Intel garbage running XP. But the same render in Blender Internal was taking 5 minutes. Each 10 seconds of the video I want to make is 300 renders. We are talking about 10 days to render 10 seconds?
And if the results were spectacularly realistic I might bite the bullet, but the result is disappointingly noisy for no good reason I can see.

render9

It looks to me like the kind of code someone fixated on the fallacy of Randomness = Panacea worship would write.
Surface roughness is supposed to be microscopic roughness, manifesting as blurriness of reflections; NOT macroscopic roughness resulting in randomness of reflections.
The difference is important, because macroscopic detail I can introduce myself via a texture. What an artist needs from a shader is mostly the simulation of optical consequences of microscopic surface features, such as blurriness of reflections (smooth blurryness; not random), multiple internal bounces resulting in what we call diffuse reflection, and effects that change with angle, such as fresnel and anisotropy. A shader introducing random noise is anathema. The funny thing is there’s a filter added to reduce noise, in the render panel, and the description says it “reduces noise at the expense of realism”, as if everything we see around us was full of noise… there IS a bit of noise everywhere one looks, walls, glass, but it is subtle; barely visible. Noise in renders is NOT “more realistic”.

There is good new and there is bad news. The good news is that you can eliminate the noise in the renders. The bad news is that you would do this by increasing the number of Samples for the render, at the expense of more time, or by using a denoiser, which is included in more recent versions of Blender.

Does your PC have a dedicated graphics card in it? If so, have you told Blender to use it for Cycles render (depending on whether it can or not) or are you rendering on CPU only?

No, my PC is total garbage. Intel CPU … AND Intel graphics chip on the mobo. I got this box for free when I got laid off in January. This was my box at the office.

This is such a pity; Cycles seems to have a lot of Right Stuff in it, like the transparency of the pipeline; but randomization has NO PLACE in graphics. I learned this the hard way, many years ago. Baking AO’s I would religiously set the app to use randomized samplings. Then I would struggle to get rid of the noise… I believed in randomization so strongly that no amount of pain could shake me from it.
Then one day I decided to try baking an AO without randomization and it was beautiful!
Randomization increases statistical precision only slightly, at a huge cost of local inprecision.
And filtering is not a good solution, because all it does is low pass filter the noise; it does not elliminate it. That’s like turning the treble knob down on a scratchy recording; you still hear the scratchiness AND the the music sounds duller.
The best policy is to NOT use ANY randomness. You can have a very patternless ray distribution, like rays spiralling outwards ftom the center at golden ratio angles, whatever, but keep it constant, NOT randomized. Random jitter is for the birds.
What cycles needs is not more filters. It needs a setting that shuts down its random number generator…
While waiting for that, I’m going back to Blender Internal.