I have some questions

[Oshyan]

What about the UV's on the terrain made by Terragen?

What do you mean?

- Oshyan

[green_meklar]

Okay, I don't know what this forum's policy on necromancy versus spamming is. Every forum seems to have their own code of conduct, so I guess I just have to hope that posting in this thread a month after the last post is considered the proper procedure as opposed to making a new one. Or that if it isn't, you guys don't get angry at me. Or at least not any more angry than I deserve. Which is probably pretty angry. I can post a new thread if you like, so if that's required by your forum customs, feel free to say so.

There are two things that are really starting to bug me. The first is the thing with the camera at long distances that I already mentioned, which basically prevents me from rendering the default planet anywhere higher than low orbit. I would like to be able to do a planet from an appreciable distance, but it looks like if I want to do that I'd have to make a new planet and move it away, which I would prefer not doing because it adds complication and I haven't even tried it yet to see if it works anyway.

The second thing (which I haven't mentioned previously) is functions. From what I've seen here, most of the decent artists swear by functions. But go figure, every single time I've tried to use functions to alter the terrain, the result has always been the same: The terrain ends up totally flat. It doesn't seem to matter what function I use, where I put it in the network leading up to the planet's terrain input, or what parameters it has. Whenever I plug a shader into a function, it invariably comes out flat. I haven't tried them on other things like water or clouds yet, but if I can't do it on terrain, there's not much point anyway. Can anyone explain what I'm doing wrong? Or is it just one of those things that will always remain a mystery to me due to my limited talent and mental ability?

[Njen]

First point.
There does seem to be some strangeness when you zoom out the camera to large distances (outside of the black sphere). Does that black sphere's normals interfere when the renderer attempts to work out what it needs to draw? Even at a quality of 1, the planet appears like it has black parts.

Second point.
Without any examples it's hard to give you any answers. Generally it seems that you are not using them correctly. If you are new to functions, I highly recommend opening up some of the setups that people have posted here, and experiment with changing various values and nodes one at a time. By understanding the results that these setups give, you can deduct what results happen when you change a value here and there.

[rcallicotte]

Do a search on nvseal.  He has done exactly what you say you can't do, though he is doing it better than any of us.  So that means you'll need practice.

This brings us to the second thing - there have been quite a few threads that do nothing but talk about making functions work.  Get involved when these take place, go through the threads that have TGCs with functions, practice what you read people talking about functions (ask more questions) and especially do what you can to do some tutorials on functions.  There have been some created just for that and you'll find them under the Terragen 2 Documentation thread.

Practice what you learn and you'll discover possibilities you don't know.

To start a function, begin with a Get Position.  Build from there by adding this to the Input of some Noise Function node and then add a Constant (try Scalar) to the Scale of the Noise Function node.  Now connect the conclusion of this to the Function input of the Displacement Shader.  Take the output of the Displacement Shader and run it through a Compute Terrain.  Take the output of the Compute Terrain and go to the input of the Base Colours or another Surface Layer.  All this, of course, goes into the Planet Surface Shader input.  Practice.  Practice.  Practice.

...which basically prevents me from rendering the default planet anywhere higher than low orbit.

The second thing (which I haven't mentioned previously) is functions.

[bigben]

There are two things that are really starting to bug me. The first is the thing with the camera at long distances that I already mentioned, which basically prevents me from rendering the default planet anywhere higher than low orbit. I would like to be able to do a planet from an appreciable distance, but it looks like if I want to do that I'd have to make a new planet and move it away, which I would prefer not doing because it adds complication and I haven't even tried it yet to see if it works anyway.

The black sphere is the project's background. It's listed at the bottom in the Objects group. It's default radius is -2e+008. Change it to -2e+010 and you should have enough room.  This render is from 4.46308e+008, 1.75682e+009, -7.43829e+008, camera FOV 6.75°

[rcallicotte]

I completely forgot about the background object.  Yeah, BigBen has it right.

[green_meklar]

There does seem to be some strangeness when you zoom out the camera to large distances (outside of the black sphere). Does that black sphere's normals interfere when the renderer attempts to work out what it needs to draw? Even at a quality of 1, the planet appears like it has black parts.

Um...as far as I know, the renderer suffers from exactly the same problems as the preview. I think I did a test for that, and the same thing happened. I just got black space where the planet was supposed to be.

Do a search on nvseal.  He has done exactly what you say you can't do, though he is doing it better than any of us.

If he's doing it better than anyone else, then that's probably a very bad place to start. You know, sort of like learning physics from Stephen Hawking or mathematics from Kurt Godel. It won't do me much good being told that a five-step scaled vector rotation tree has to be plugged into five Turing-symmetrical voronoi displacement networks merged using a universal slope scalar smoothing node with a ceiling variation value of the derivitave of pi squared and a reverse offset shear input from a cylindrically mapped radial altitude converter indirectly blended with a disabled atmospheric shader that utilizes a memory bug in the program's built-in limitations on negative 64-bit floating point variables if I don't understand why.

This brings us to the second thing - there have been quite a few threads that do nothing but talk about making functions work.  Get involved when these take place

So far I've seen lots of threads praising the power of functions and the elite people who make wonderful honeycomb and melted plastic landscapes out of them, but I don't recall seeing any that were saying anything useful for me. It seems like every last person here started out at the 'functions work, now you just need to figure out how to make something cool out of them' level the first time they opened the program, which is one step ahead of the 'functions either make everything flat or produce infinite displacements that mess up the preview and turn the terrain into an array of giant needles' level that I'm at right now.

To start a function, begin with a Get Position.

Is that something you always have to do?

Build from there by adding this to the Input of some Noise Function node

Oookay... The strange thing is, whenever I change even one aspect of your setup, the terrain has a tendency to either go completely flat, or do something really weird like develop extremely long spikes that stick up into the air. It messes up most particularly when I try to plug a power fractal shader in, which is something I've seen in screenshots on these forums and which seems to work fine for other people. I'm afraid your setup, while functional (no pun intended), doesn't really give me any understanding of how these things work. You know, sort of like little kids knowing that 99+1 is 100 just because they've heard it, without knowing why that's the case. Examples are all very well...but only if they're demonstrating a principle I can understand, not just for the sake of their own existence. I hate to sound so helpless, but it's just not that easy to learn by practice when 97% of the things I try fail in exactly the same uninformative manner. I think it would do me a lot more good just to know what it is that is done by the program when one attaches the functions and the shaders together. Even if it involves advanced mathematics, at this point I think I'd prefer that to figuring it out by...by...experimentation alone. *shudders*

and then add a Constant (try Scalar) to the Scale of the Noise Function node.

So I take it that simply typing in numbers in the fields where it says stuff like 'min' or 'scale' is totally ineffective?

The black sphere is the project's background. It's listed at the bottom in the Objects group. It's default radius is -2e+008. Change it to -2e+010 and you should have enough room.

Okay, I tried that... Now at least the render is showing the planet properly from a distance, however the preview is still running into problems. That is to say, it only shows the atmospheric halo and not the part of the planet with solid ground. If you haven't seen this 'atmospheric halo' effect before, I can always get a screenshot. Wait, never mind. I don't think there's anything left in this program you haven't seen before.

[rcallicotte]

green_meklar - Go to this URL http://forums.planetside.co.uk/index.php?topic=1266.0 and start here.  This is a very simple use of functions and if you don't understand what everyone is talking about go to the bottom of this page to find the TGD that might help you by offering you the opportunity to play around with it.

[Oshyan]

The preview has limitations due to its detail level. This is just inherent to how the detail levels work. If it doesn't look right, I'd suggest just doing a quick render. Time-wise it isn't particularly slower and you can control the detail levels more explicitly.

- Oshyan

[bigben]

...

and then add a Constant (try Scalar) to the Scale of the Noise Function node.

So I take it that simply typing in numbers in the fields where it says stuff like 'min' or 'scale' is totally ineffective?

Correct. You need to connect numbers to function inputs via a Constant (scalar, colour or vector) node.

[green_meklar]

green_meklar - Go to this URL http://forums.planetside.co.uk/index.php?topic=1266.0 and start here.

Wow...if anything, that thread just underlines how much the functions are beyond me. You said to start with just get position and not plug anything into that and go straight to add noise, yet in that thread ProjectX (who I'm definitely going to get mixed up with an online acquaintance named Project_Xii) says you have to plug a power fractal into the get altitude and then put a Y to scalar right after that before you start doing anything. Knowing about certain setups that work without knowing why they work is looking more useless by the minute. I'm aware that I seem to be annoying you all pretty badly with my blatant ignorance and inferiority...but surely someone must know how the functions work. Or is it something that can be understood, but not explained?

The preview has limitations due to its detail level. This is just inherent to how the detail levels work. If it doesn't look right, I'd suggest just doing a quick render. Time-wise it isn't particularly slower and you can control the detail levels more explicitly.

So in other words there isn't really any way to fix it in the preview? That's kind of annoying, but I guess I can live with it. Normally I don't like to do quick previews just to adjust something like the camera, because of my slow computer speed. Instead I'll probably end up having to keep track of the planet's location just by using the atmospheric halo.

[Oshyan]

Use of the function nodes depends *heavily* on a decent baseline understanding of math and especially how mathematical functions translate into 3D space and use in 3D graphics. Previous experience with a shader language like Renderman or Maya's shader node system can help a lot. If you don't intuitively understand mathematics translated into 3D space then it's going to be a struggle for you the whole way.

I think you may be operating under the mistaken assumption that using function nodes is somehow necessary to achieve the best quality scenes, and that's not at all true. In fact the vast majority of people posting images here do *not* use functions. There are maybe 5 people here that are really producing good stuff in the function nodes - Efflux, Volker, ProjectX, and a few others - the rest are all using more conventional (and easy to understand) approaches.

So unless you're seeing something being done in functions that you really want to be able to do in your own scenes, I would just not bother trying to deal with them. For people to whom their use comes naturally they are great, but I just don't think it's worth struggling to learn them when there are many other useful techniques that are easier to understand and use.

- Oshyan

[Njen]

Just to back up Oshyan, the same goes for me too. I hardly ever use functions to get what I want. Also I agree, that if you do not know anything about math in 3D graphics, then trying to understand functions in TG2 from an entry point would be like trying to learn a foreign language by picking up a random novel and attempting to read it. You need to know the 'alphabet' of math in 3D graphics to understand what functions do. I would suggest any beginners book to math for 3D graphics, there's plenty out there.

[green_meklar]

Previous experience with a shader language like Renderman or Maya's shader node system can help a lot.

Haven't got Maya. Haven't got Renderman, whatever the hell that is. But I have used Art of Illusion, and I think it has similar stuff...although maybe it looks more similar than it is, especially judging from the fact that it's so much easier to use.

I think you may be operating under the mistaken assumption that using function nodes is somehow necessary to achieve the best quality scenes

That depends what kind of scene you want! Power fractals and all can look really nice, but they still don't give you the kind of control required to tweak the terrain precisely the way you want it. I learned this the hard way.

So unless you're seeing something being done in functions that you really want to be able to do in your own scenes

I am. But if what you say is true, it's probably not worth it. I'm used to being a permanent, incurable noob anyway, so it's something I know I can take. At least for a while.

For people to whom their use comes naturally they are great

Nothing comes naturally for me.

[Cyber-Angel]

green_meklar,

I can awnser you first question: RenderMan is a Renderer from Pixar and has been used in many films information about it can be found here https://renderman.pixar.com/  and also this list of films made using it on Wikipedia http://en.wikipedia.org/wiki/List_of_films_made_involving_PhotoRealistic_RenderMan

Can I just add that no one said that learning TG2 was going to be quick or easy and come to think of it painless, but at the end of the day ask the questions you have when you get stuck and there are plenty of people here who can help you solve them, that is what this community is for.

I remember when a few years ago I started to take what I was doing with Terragen more seriously rather than some thing to play with while waiting for a file to download form the Internet I my self had questions about how to make more open terrain in version 0.9.43 and was simply told to move the camera zoom slider and sure enough the kind of terrain I was looking for.

Over time I asked more questions, they where answered and I began posting first on Renderosity and then on Ashundar and I paid attention to the comments on the images I posted so that those lesions could incorporated into future work, these people some of them are members here know who they are: I hope in time you will learn TG2.

In the mean time have a better one.

Regards to you.

Cyber-Angel