trying to create a metal shader without textures just power fractal for roughness and color.
lighting adjustedmetalLighting.jpg
Trying bringing your Index of Refraction above 2. It will give stronger metallic like shines.
Have a look here for reference too (if you already have not of course):
https://planetside.co.uk/forums/index.php/topic,22695.msg229027.html#msg229027
increased IOR to 2.9 metalIOR.jpg
Quote from: Beep the Meep on January 21, 2020, 06:05:02 PMincreased IOR to 2.9 metalIOR.jpg
Very nice. Much more metallic looking. The PF roughness looks nice as well.
For metal you might go much higher. Try something like 10 or 15. Also if you put your fractal color in the specular color and set the diffuse to black, it should really look like a metal!
Quote from: KyL on January 21, 2020, 10:46:36 PMFor metal you might go much higher. Try something like 10 or 15. Also if you put your fractal color in the specular color and set the diffuse to black, it should really look like a metal!
I'd say that's quite high. I haven't even seen that used for gold/silver etc. But for rough metal like this it might also be pretty high in general. More a chrome look (which btw I have also not seen with a index so high).
Curious if you have examples? I'd like to see.
Higher values certainly look better, but real refraction indices are never that high, strangely.
Indeed this is counter intuitive but it had to do with the way we use a fresnel approach for our metals. Metal responds to light differently and some renderers have a dedicated shader/mode to that.
(https://files.mtstatic.com/site_7337/179/0/webview?Expires=1579702005&Signature=ntGbVhctsyjUPTxQoEG9gP2Rvgyz-691zhAY42MLhJoFfqrizCwam5Zk2hVmBODC42Ouor6r6q8FV8yT~XjTL3wrM99-~gZIBbNVqdnNXAFUBeE50ejYQv0f6BzL49jIzZJKOBWpX3F98PzcrhaTNQuRsIi7MYxFPKfL~v7ll1w_&Key-Pair-Id=APKAJ5Y6AV4GI7A555NA)
If you look at this graph, the visible light the human can see will start roughly at 400nm. For most metals, especially Aluminum, this will mean a reflectance close to 1. The fact that metals reflectivity ramps up so quickly depending on the wavelenght means that it's mostly pure reflections. To simulate this behavior you would have to crank up your IOR pretty high, between 20 or even 50. Chromium, on the other hand, is more a coating than pure metal and won't need such a high IOR. 5 should be enough.
I do not know which BRDF the default shader uses for specular reflection, but I assume it to be a Ward or something similar. I may be plainly wrong here and I hope Matt would correct me, but I've seen this approach used on many other renderers on many scenarios!
KyL's right.
Since TG does not offer shader models which can make a distinction between dielectrics (sand, plastic) and conductors we assume the visibility of a metal is due to its reflectivity and thus diffuse is 0.
Increasing IOR then assures we get an entirely reflective surface.
That's where KyL's suggestions came from.
When using a shader model capable of handling conductors then IOR is not needed to increase the reflectivity and a more physically plausible value can be used.
In the end the index of refraction is the difference in speed of light between a vacuum and a material and it's not that the speed of light is 20 or 50 times slower in metals, it's just that TG's shader model is dielectric, so we need to cheat.
Here's a nice little read which popped up in my mind:
https://www.chaosgroup.com/blog/understanding-metalness
@KyL I believe the reflective shader model can be chosen? Blinn or Blinn-Beckmann if I recall correctly.
I don't know the default method for speculars in -say- a default shader...hmmm...makes me wonder.
It's an approximated BRDF I'm pretty sure of, since we can't control fresnel for instance.
You can make a fresnel-like shader though from blue nodes and feed that into a reflective shader's roughness input (with roughness set to 1 iirc)
Great article, thanks for sharing.
Yes I remember that you can chose in the reflective shader, but now I almost never use it, except for a clear coat layer. Maybe Matt can shed some light on the BRDF the default shader uses!
Thanks for the article, very interesting read!
I'm simply referring to how metals are done in TG for desired looks. For example. Download my metal shaders or Hannes or anyone elses..those values are excessive. I thought that would have been obvious from veterans.
When he already has looks pretty much like painted rough metal. Going higher would start to kill that look and be a colored chrome, and wouldn't make much sense with the roughness of the sphere.
Additionally because this is coloured metal zero diffuse doesn't apply, unless this is actual green hued metal itself.
Here's one of my old rusted chrome balls, good example of rough metal that's shiny, and a IOR of 7 is plenty.
BTW this is PT as well.
Edit: I took a look at Martin's article, and it's a great resource, but doesn't apply to Terragen. For example the IOR for silver and gold right out the door in even their revised chart, would not work in Terragen. In fact they're in the range I use for dull rock and wood type stuff.
Quote from: WAS on January 22, 2020, 04:23:27 PMEdit: I took a look at Martin's article, and it's a great resource, but doesn't apply to Terragen. For example the IOR for silver and gold right out the door in even their revised chart, would not work in Terragen. In fact they're in the range I use for dull rock and wood type stuff.
I clearly stated that in my post, actually ;)
Quote from: Tangled-Universe on January 23, 2020, 09:47:15 AMQuote from: WAS on January 22, 2020, 04:23:27 PMEdit: I took a look at Martin's article, and it's a great resource, but doesn't apply to Terragen. For example the IOR for silver and gold right out the door in even their revised chart, would not work in Terragen. In fact they're in the range I use for dull rock and wood type stuff.
I clearly stated that in my post, actually ;)
Not clearly, at all. In fact you made no real distinction, in addition to no benefit to the post than. We are talking about IOR in Terragen and what's needed. Clearly KyL knows this going 20, or I above 2. So besides just trying to assert some superiority negligently, what was your post about? You added nothing including a suggestion on topic with the post. Just trying to argue?
Quoteit's just that TG's shader model is dielectric, so we need to cheat.
Seems clear to me. ;)
Honestly, Was, please take a break. Everyone who posts on this forum means well.
Quote from: sboerner on January 23, 2020, 05:04:11 PMQuote from: undefinedit's just that TG's shader model is dielectric, so we need to cheat.
Seems clear to me. ;)
Honestly, Was, please take a break. Everyone who posts on this forum means well.
Not regarding posts to me. Lol They're passive aggressive.
Additionally, that's not clear in the slightest to someone trying to figure out the shaders (not even me, these specifics mean jack-all to using IOR from any source in TG, which simply doesn't work, so no need to debate about those specifics and not about the specifics relevant to TG). That's incredibly technical. Lol "And cheating" is no explanation of how to use them in TG. Which entirely nullifies the tangent post.
WAS, it's unfortunate that you aren't aware of the irony in your statements. This is the kind of language that got you in trouble last time. I strongly suggest you come back on another day when you are in a different mood, otherwise it won't end well.
Oh threats now? Lmao I have said nothing wrong, in fact facts. Martin is mad at me. And been following me around just like Oshyan to leave long winded technicalities just to start stuff or try to be the "actually I said that" in a vague and not explained way. Lol like here a whole irrelevant rant to the topic about IOR in TG. And not even how it could relate....
Technical drivel for Superiority is not helpful here... Especially for obvious novice questions.
Quote from: WAS on January 23, 2020, 06:57:44 PMOh threats now?
They don't compare to the ones that you've sent me, so I won't feel bad about it.
Quote from: Matt on January 23, 2020, 06:59:30 PMQuote from: WAS on January 23, 2020, 06:57:44 PMOh threats now?
They don't compare to the ones that you've sent me, so I won't feel bad about it.
Over these actions here, how ironic. Too. Lol What have I done wrong, you need to be very clear. All I've said is it's not clear. It wasn't too me, I doubt it will be to someone trying to use Terragen' IOR which is irrelevant from sources, seemingly being a novice in the software, or even more with 3D graphics. It could have been faaaar clearer.
Quote from: WAS on January 23, 2020, 07:03:56 PMOver these actions here, how ironic. Too. Lol What have I done wrong, you need to be very clear.
I don't
need to be anything but I will try one last time because I would want someone to do that for me if the situation were reversed. So here's a prime example:
Quote from: WAS on January 23, 2020, 02:03:03 PMSo besides just trying to assert some superiority negligently, what was your post about? You added nothing including a suggestion on topic with the post. Just trying to argue?
For more detail, refer back to the emails we exchanged last year. I tried very hard to explain it to you back then. I won't go through it a second time.
QuoteAll I've said is it's not clear.
You said a lot more than that.
QuoteIt wasn't too me, I doubt it will be to someone trying to use Terragen' IOR which is irrelevant from sources, seemingly being a novice in the software, or even more with 3D graphics. It could have been faaaar clearer.
It could have been far clearer to you. But you don't know how useful Martin's post is to other people. You don't speak for everybody, you don't know how other people think or feel. They understand things you do not, no matter how hard it is for you to accept that possibility. The difference is, most other don't tell you when you are talking rubbish because it's not polite, whereas you can't stop yourself from telling other people when you think they are. This is bullying and it had better not continue on this forum.
Furthermore, I don't owe you anything after the crap you pulled on me last year, so don't expect me to explain any further.
Quote from: Matt on January 23, 2020, 07:40:38 PMFor more detail, refer back to the emails we exchanged last year. I tried very hard to explain it to you back then. I won't go through it a second time.
How about no? That's irrelevant. Martin was chiming in on the IOR discussion. Then had to passively aggressively say it's clear. Well it wasn't to me, and I was the one that said it, and was quoted. Not the OP. Regardless though, the OPs post, since we're talking about "clear-lies" to your last bit; his post seems to clearly imply he doesn't understand that aspect, so not connecting real world IOR to Terragen doesn't seem to have any impact on the discussion... So what ARE good values to use? When people are highly technical, it's hard for them to think outside this scope in relation to learning. Why it takes a certain mind to teach.
Also regarding
Quote from: Matt on January 23, 2020, 07:40:38 PMI don't need to be anything but I will try one last time because I would want someone to do that for me if the situation were reversed.
Personally you can do whatever you want to, but when it comes to liabilities on administrative action on peoples accounts and your rules, you should reconsider. That could be costly, all for arrogance.
Quote from: WAS on January 23, 2020, 08:04:19 PMPersonally you can do whatever you want to, but when it comes to liabilities on administrative action on peoples accounts and your rules, you should reconsider. That could be costly, all for arrogance.
Notwithstanding your interpretation of the law, my suggestion remains.
Streisand effects aside, what is being accomplished here? Typical PS instigation tactics? I still don't see what the discussion was about in relation to TG, or how KyL may be using excessive IOR which may increase render time to achieve the desired result.
I mean in general we know physical IOR doesn't relate to TG, why we're talking the numbers we were.
And it's really interesting you chime in to harass me about not thinking things are clear for the topic, when you could be inputting. You know your IOR the best. What would be the correct IOR for a shiny metal, dull metal, chrome, etc? Or is my input about past materials and my own more or less the trick?
Some action in the forum! But not the sort of action I (for one) need. It used to be a lot more decent, once.
Quote from: Dune on January 24, 2020, 12:59:46 AMSome action in the forum! But not the sort of action I (for one) need. It used to be a lot more decent, once.
They never really have. All the past is public. Lol It's routine users get fed up with the PS. I've been here since 2014 and a file harvester since like 2010.
And how can you not be mature enough at your age to realize you are instigating, perpetuating the problem and somehow think you are not part of it? Lol
Yearly unrest or couple times a year in these forums since about a year after nothing was done to TG2. It's like a holiday for this community.