here is a link to fundamentals of physical geography, there is some inf on Glaciation as well as other aspects of geology .several pics. http://www.physicalgeography.net/fundamentals/chapter10.html
SeerBlue
I’ve been reading through a book I have on mountain geomorphology.
Regional surveys of topographic attributes of mountian ranges have served to highlight basic down stream patterns.
The book maps out process domains on a graph of local slope vs drainage area and summarises it:
Plot of upstream drainage area versus local slope showing the charactersitic domains of key processes in erosional landscapes. Within these domains, the exact nature of the area-slope relationship for a given process depends on local conditions, and specifically on the rock-uplift rate, mean precipitation and precipitation variability, and rock-mass properties.
Starting from the top and going downstream one might find the folowing sequence of process domains in a river catchment (the river catchment, or drainage basin, is all the land from the mountain to the seashore, drained by a single river and its tributaries):
(bedrock) hillslope,
debris flow-channel,
bedrock river channel,
mixed bedrock-alluvial channel,
coarse bed alluvial river channel,
fine bed alluvial river channel
Possible Process:
Create initial DEM sans fluvial erosion.
Determine map of local slope/drainage area using terrain analysis in a GIS program (eg SAGA).
Use that map as input to control macros which have been designed to mimic the above process domains, or at least their visual appearance.
In addition the inclusion of a device which could model very simple precipitation amounts and variabilty, coupled with rock hardness maps. This would give all of the parameters (except rock-uplift rate) identified above to be used in the macro.
Perhaps even vegetation could be included ultimately as it also has an impact on sediment transport.
Not sure if it would work, but that’s one idea.
monks
The major problem is this: Terrain Modelling by classification will always have problems with transitions and “realism”.
We can look at a terrain that has been created by nature and classify the various sections of it in many different ways, both on a very broad and very specific scale.
However, although some classifications are quite geologically based (ie, mountains made via uplift versus volcanism), others are merely our attempt to better describe what in nature is a fluid continuum. Thus, it really isn’t possible to model them in isolation and expect the results to mesh together in any easy way.
I certainly have some ideas that help solve the blending problem quite a bit, and I’m currently doing a bit of R&D on a couple of them. If they work out, awesome, the new devices will probably make their way into Pro. If not, then they don’t work. We’ll see. But even then all it does is blend between different characteristic land types better: there’s still no overarching method to the madness.
That kind of outcome will have to wait for something a little more next-gen. So many things to try, and so little time to do it in…
We can look at a terrain that has been created by nature and classify the various sections of it in many different ways, both on a very broad and very specific scale.However, although some classifications are quite geologically based (ie, mountains made via uplift versus volcanism), others are merely our attempt to better describe what in nature is a fluid continuum. Thus, it really isn’t possible to model them in isolation and expect the results to mesh together in any easy way.
Yes, I take your point that there are no really perfect classification schemes. As soon as you look into those, they immediately proliferate along what question you are asking about what.
Perhaps the way to classify them is by classifying the macros by visual similarity to a morphology or terrain type- but then we are back to classifying terrains, but at least not by theory or process. So you are classifying macros, not natural landscapes, the output not the input. This surely is what Geocontrol has done in fact. It makes no pretense at simulation of a process.
I certainly have some ideas that help solve the blending problem quite a bit, and I'm currently doing a bit of R&D on a couple of them. If they work out, awesome, the new devices will probably make their way into Pro. If not, then they don't work. We'll see. But even then all it does is blend between different characteristic land types better: there's still no overarching method to the madness.
That still sounds very useful- and no doubt will be awesome :).
I imagine that the tech behind the future spectral combiner may have some good applications for blending- using FFT to isolate noise frequences. Would that would be useful for blending?
I keep thinking about the potential for rivers regards blending - and deep down I’m sure I’m on the right track :lol: The river would have to carry and deposit sediment, that would be crucial Surely rivers are maps in themselves. Even from a purely toplogical point of view, they are maps, because you can determine where the steep and shallow gradients are from river courses. Add to that the fact that they also map the geologies because the underlaying substrate determines to some extent the course of a river. There are other factors but that’s a start. If you can extract such information about a landscape from a river, then you can also input it to determine the landscape via the river- does that make sense?
monks
I was thinking today if there might be a possible way of making a device like this?
An idea for River System Networks.
A modification of the current Erosion Device but with isolated channel flow points from the highest elevation… in other words every time an erosion device is attached to a perlin the erosion occurs at every high point but with a River Device the the effect is isolated and scattered around abit while remaining at the highest points while such a device would allow the isolated channel flows to work themselves farther out to the lower parts of the terrains but remain digging into the lowest points winding through basins, plains, valleys etc… the isoflows can have devertion controls, certain complexity controls, displacment type controls and as it finds the lowest point it fills a hard edged subtraction operation for a lake or larger body like a sea or ocean by filling in black areas depending on how much subtraction a user wants that can be controlled with a fill size slider… at the end of each low point the device can have delta creation operation by splitting into additional channels before filling in the lowest parts with the black… the deltas can be randomized and or limited in how many are to be formed…
sounds nutty? probably… how might it work? i have no idea… does this even make sense… :?
“A full stop or period (sometimes full point or dot), is the punctuation mark commonly placed at the end of several different types of sentences in English and several other languages.”
Yes, the way you describe is basically a simulation of real rivers. We should split it into several smaller problems (divide and conquer)
- the rivers shall behave differently in some places (where there’s hard rock or in lower areas)
- that should be possible with some masks
- for the single styles you propably have to write a macro
- Deltas… that is somehow inverted erosion, that could be tricky but possible
btw: I couldn’t build a glacier macro that is independent of user-made-masks yet
Yes, i agree that we should split it into several smaller problems as this is a complex task. I think this may be better suited for a plugin rather then a macro but i could be wrong and if this is possible would take looking into the internal structure of the erosion device for example if such a thing is possible. For a plugin i would try at this myself but i know knothing about programming math operators sense i have more of a artists mind set. I just think of these wacky ideas but have no clue about how the programming works. You have to excuse my unorthodox grammar structure, it is a bad habit and i write storys to so go figure. 
Yes, a plugin could propably do the better job… but as you said it is much more difficult too.
PS: The quotation only says “commonly” anyway. :mrgreen:
About the new and old erosion mixing.
I wonder if the Spectral Combiner for the Pro version might do the trick? Something to test that idea later atleast.
OK, a network for glaciers is ready…
Looks quite nice, doesn’t it?
Yes, it does. 8)
Nice Indeed!
:o Very nice indeed! Share, share! 
- Oshyan
it does look verynice indeed… SeerBlue
Hi All,
Late to the game but is Sethren’s pdf file still floating around somewhere. Sethren, is this still available? Thanks
Rich