Lead-In Scale defined

[elipsis1]

I did do a search on the forum, and wanted to verify what I have learned, so I apologize if you guys are getting tired of all my posts 

So lead in scale is the "Largest" size feature, followed by "Feature Scale" which would be the scale at which most of your scene is at.  Finally the "Smallest Scale" which is pretty much self explanitory.

Is this correct?

You would generally not want a Lead-in scale smaller than your feature scale correct?

Thanks for your patience, and for any answers!

Scott

[rcallicotte]

Check this link out.  [edit]oops, forgot the link - http://forums.planetside.co.uk/index.php?board=2.0[/edit] I got this from #5 in the list.  Oshyan explains,

"Now let's look at each of the various settings tabs. The Scale tab is selected by default and you will find several controls for scale here. Scale basically controls the overall size and distribution of the patterns in a surface layer. These patterns are generated by a fractal noise shader which is internal and in the case of the Base Colours node. The Feature Scale setting determines the overall average scale of features in the shader and this will have the most noticeable immediate effect on scale. The Lead-in Scale is essentially the size of the largest features that will be present in the shader output and naturally Smallest Scale then determines the size of the smallest features. All of these are measured in meters, the default unit of measurement in Terragen 2.

The range between the Lead-in Scale and Smallest Scale will determine the number of "octaves" of noise that are generated. This value can be changed directly if you have an idea of a specific detail range you want, but generally it's easiest to adjust the other Scale values. Note however that the more octaves each of your shader nodes are generating, the longer your scene will take to render. The effect is not significant for only a few shader nodes but it can quickly add up, especially when displacement is involved."

[penboack]

Think of the Lead-in Scale as the size of the mountain range, and the Feature scale as the size of a typical mountain.
Smallest scale may be used to limit the amount of fine detail produced, could be used to improve performance.

[nixx]

penboack,

that was the best, most descriptive explanation of the fractal scales (which have tortured me too) I 've read.

thanks

[rcallicotte]

I'm not 100% sure this is an accurate description.

Think of the Lead-in Scale as the size of the mountain range, and the Feature scale as the size of a typical mountain.
Smallest scale may be used to limit the amount of fine detail produced, could be used to improve performance.

[rcallicotte]

"So basically all this is about the lead-in scale, ect parts of the fractal (at least on the main question)? and so far the answer is that "Lead-in scale" is roughly equivalent to Maximum and "smallest scale" is roughly that of minimum and that feature scale is some form of multiplier? " - Will

"Your Lead-in and Smallest Scale definitions are essentially correct. however Feature scale is roughly equivalent to "average scale", *not* a multiplier." - Oshyan


"The Feature Scale setting determines the overall average scale of features in the shader and this will have the most noticeable immediate effect on scale. The Lead-in Scale is essentially the size of the largest features that will be present in the shader output and naturally Smallest Scale then determines the size of the smallest features.", taken from here - http://forums.planetside.co.uk/index.php?topic=22

[Hetzen]

I'm not 100% sure this is an accurate description.

Think of the Lead-in Scale as the size of the mountain range, and the Feature scale as the size of a typical mountain.
Smallest scale may be used to limit the amount of fine detail produced, could be used to improve performance.

To be fair, I think it sums it up pretty well visually.

[rcallicotte]

@Hetzen, if it helps...but it does help me to think of a cloud - in TG2, a cloud has a basic size of Features, which is enhanced by the Lead-In value to proportion the larger puffs and sections in the cloud.  And the details are in the Smallest Scale.  The greater the octave count, the greater the detail.

I can see the clarification by penboack, but see a need for clarity.  A range of mountains in TG2 would have all sorts of detail produced by the shader scale, so it's not as easy for me to relate that definition to this.  Whereas the quote from Will above talks about Maximum and Minimum while Oshyan defines the Feature as an Average. That makes a lot more sense to me, especially when talking about noise.

And it's greatly useful for us to discuss this, since it is only making me think about this in a better light.

[efflux]

In other words shouldn't they be called largest feature scale and smallest feature scale?

[dandelO]

Penboack's description is exactly right.

'Lead-in' defines an overall area that the 'feature scales' will be applied to. 'Smallest scale' is how much the 'feature scale' is broken up. The larger the difference between 'feature' and 'smallest' scales, the more octaves there will be.
Since it is random fractal generation, it is obvious that the feature values will be averaged.

[rcallicotte]

I wouldn't say exactly or it would have made sense to me.  I can't see Feature Scale equaling a mountain, etc.  The best definition for me is what was already in the documentation.  I think that Penboack's definition might be a way for people to visualize it, but seeing it as a noise rather than a mountain helps to see it as it is.  As I mentioned, playing with clouds brings this out even clearer.

Penboack's description is exactly right.

'Lead-in' defines an overall area that the 'feature scales' will be applied to. 'Smallest scale' is how much the 'feature scale' is broken up. The larger the difference between 'feature' and 'smallest' scales, the more octaves there will be.
Since it is random fractal generation, it is obvious that the feature values will be averaged.

[reck]

Why was largest scale called "lead-in" and not largest scale? I think this adds to some of the confusion.

Wouldn't this naming be easier for people to understand?

Largest Scale - > Average Scale -> Smallest Scale

[Kadri]

Why was largest scale called "lead-in" and not largest scale? I think this adds to some of the confusion.
Wouldn't this naming be easier for people to understand?
Largest Scale - > Average Scale -> Smallest Scale

Nah! That is too easy ! Then what should we writing here on the forum like this thread  

[reck]

Why was largest scale called "lead-in" and not largest scale? I think this adds to some of the confusion.
Wouldn't this naming be easier for people to understand?
Largest Scale - > Average Scale -> Smallest Scale

Nah! That is too easy ! Then what should be writing here on the forum like this thread 

Ah so that's the reason. Now I know 

[dandelO]

The general rule is; lead-in=largest, feature=size of features that are within the lead-in area, smallest=how much the 'feature scale' is divided into smaller features. Whether seen as mountains, noise or clouds makes no difference really.