Hi,
Is there a way to move a layer of clouds ? I 've tried a few combos of vector/position nodes but nothing seems to work. Maybe it's just me (quite probable ;)) but I can't get it to work.
Say you have a cloud layer you 're satisfied with, but you need to slightly offset the clouds' position (or, in the animation-enabled version, maybe even animate the clouds drifting & billowing). How would you go about it ?
thanks,
nick
I think wraping the clouds should work
I assume you mean "warping" ;) (if not, please correct me !)
That could be a possible workaround, yes, but what about straight-line motion ? Think time-lapse movies of low-altitude clouds being carried away by winds...
Any ideas ? I 'll keep looking into it myself, but if anyone has any suggestions I 'd love to hear them :)
thanks,
nick
I am not sure what you are trying to say but you can animate the "Lead-in wrap effect" for you movement and probably animate buoyancy and clumping for you billowing effect. I am still trying to figure out what the whole "noise variation" part does but as far as I've tested those settings....they should work for you
yeah i think i know what u mean... and no i dont think its possible right now
Quote from: dhavalmistry on January 23, 2007, 10:58:56 AM
I am not sure what you are trying to say but you can animate the "Lead-in wrap effect" for you movement and probably animate buoyancy and clumping for you billowing effect. I am still trying to figure out what the whole "noise variation" part does but as far as I've tested those settings....they should work for you
Animating the lead-in warp does produce a certain kind of motion, but again, it's not exactly what I had in mind. I was talking about moving the cloud layer towards any direction you choose, which I still haven't figured out how to do (if at all possible). But your suggestion provides a limited workaround, at least until a better way to do it comes along.
Quote from: buchvecny on January 23, 2007, 11:16:40 AM
yeah i think i know what u mean... and no i dont think its possible right now
Well, like I said, I 'll keep looking into it, and if I find anything I 'll post it here. (unfortunately I still only have the free version, so no animation for me - so I use the "tweak-and-watch-the-patterns-change" method ;))
nick
I can't believe it was that simple, and yet I missed it !
There's a "Transform Shader" there :) Just plug the cloud's density shader into a Transform shader, and then go ahead and adjust the XYZ translation and scale !
I think the reason I overlooked this was that I was looking for a solution in the function shaders, while this is located under the "other shaders" menu.
Now all I need is the commercial T2TP (and lots of patience for rendering) in order to do some "real" tests !
nick
Thanks for finding the transform node :)
I am having luck animating time lapse coulds using the transform node along with animating the noise octives.
While animating the transform would be a nice way of moving the clouds, what we need is some sort of 'phase' value, to make them change their pattern slowly without compromising on the valules that make up how it should look like.
Correct, the Transform shader (specifically the Translate function within it) is the best way to "move" a layer of clouds currently. Translate along the X or Z axis (or both) to get planar motion. If you translate along Y, rather than get real vertical motion, you will get something more like shape variation. The cloud plane essentially samples the noise function within an "altitude" range and translating along Y moves the noise shader relative to this sampled area. As the shader moves into and out of the sampled area parts of the cloud will appear to slowly grow and shrink, in a surprisingly realistic manner. Worth a try for the effect you're aiming for. A more specific "cloud morph" function for realistic cloud evolution would be nice as well, but it may not be something we can implement for the initial 2.0 release.
- Oshyan
Thanks for the detailed description Oshyan. So in other words, you 're not moving the clouds themselves, you 're just moving the "pattern" that makes them up. It's no different than the way procedural patterns behave in most 3D apps, really.
I 'm obviously just speaking for myself here, but I don't think a "cloud morph" function would be that important - the described technique works surprisingly well (judging from other apps).
nick
Yes, that's correct. True, realistic cloud motion would take some more work and possibly a dedicated function or shader, but you're right that this simple approach yields surprisingly good results.
- Oshyan
I am a meteorologist and have a passion for 3D (volumetric) clouds and am always looking for a better way to animate clouds. For about 5 years I have been using Lightwave with a plugin called Ogo-Taiki. Like TG2 this plugin uses procedural textures and cannot specify individual clouds just a sky populated by clouds the number of, density of and form of which can be controlled. Like the Technology Preview of TG2, Ogo-Taiki requires long render times but that's the cost of realism.
I divide cloud animation into three parts. 1. large scale motion of clouds in the atmosphere i.e. clouds follow the winds, 2. growth/decay - evolution of individual cloud elements i.e. is condensation or evaporation dominant. This could be expressed as vertical growth in cumulonimbus (thunderstorm) clouds or increasing density in stratiform clouds or a combination of these or other factors you may come up with. 3. Small scale variations, these I treat as random variations that have smooth transitions from frame to frame. In other words I do not want things just popping into and out of existence for a single frame. They are fine detail which follow from the physical processes that cause the clouds. Examples are the cauliflower-like bulges on a cumulus cloud or thin patches in a deck of stratus clouds, or edge detail (wispy vs. hard). At the landscape scale we do not worry about physical reality of these small small variations, they are aesthetic detail and add realism.
In TG2 a transform shader is great for #1 (in Lightwave an object is moved and the clouds follow the motion of the object to which the texture is assigned).
I am new to TG2 and because I could not do what I wanted with clouds in TG I never really used it much. So those of you who know TG2 much better than I do (almost everyone!) try to divide your cloud animations into three parts and deal with each part separately. It really does simplify the process. Move the clouds with the translate function of a transform shader, and come up with techniques on increasing vertical extent and/or density for item #2 and come up with ways to manipulate procedural textures for fine detail in item #3.
Here is hoping that TG2 will some day allow a volume, defined by a 3D object to be filled with a 3D procedural texture to create an individual 3D cloud. In Lightwave this seems to be an easier way to get individual clouds than a particle system.
While I learn TG2, anyone have any ideas? By the way the node network of TG2 is great!
-Steve Horstmeyer
You know as well as I do that cloud movement, formation and dissipation is a highly complex process involving thermodynamics, Gas and Hydrodynamics and the Navier-Stokes Equations among other things. In its current form the Atmosphere model in TG2 is no where near sophisticated enough to do cloud motion in a physically correct, photorealistic manor and you would have to rewrite it from scratch again and that would take vast amounts of time.
In its current form Terragen dose not have an atmospheric circulation model that I can see for air currents and air circulation, also while it has a sun or multiple suns these play no part in the formation of clouds within Terragen and there is no evaporation model between the sun/s and water bodies at this time.
Real clouds have complex movements of air inside them which are a major source of cloud movement as well as temperature gradients within the cloud and relative wind speed and direction.
Other things' missing for the model and this is by no means complete:
• Advection (Follows Isobaric Surfaces, Predominantly Horizontal)
• Air Density
• Air Mass
• Cloud Albedo (Variable from less than 10% to more than 90%: Dependant on droplet sizes, liquid water or ice content and sun zenith angle).
• Cloud Dispersion
• Cloud formations expand and react to other clouds
• Cloud Optical Thickness
• Cloud Particle Sedimentation
• Cloud Top Pressure
• Cloud Top Temperate
• Cloud Translucency
• Coagulation
• Coalescence
• Cold and Warm Fronts
• Collision
• Condensation Level
• Condensation Nuclei
• Condensation Rate
• Convection
• Convergence
• Degree of Saturation (Rising Air)
• Dew-Point
• Differential Light Scattering
• Droplet Size Distribution (Maximum Drop Size 5.5mm)
• Dry Adiabatic Lapse Rate (Consistent Value at 1°C/100 Meters)
• Dry Air
• Dynamical Cooling/ Heating
• Eddy Updraft
• Equilibrium Point
• Equivalent Potential Temperature (Also called: Theta-e)
• Evaporation Rate
• Geometrical Optics
• Humidity
• Latent Heat
• Lifting Along Frontal Zones
• Liquid Water Path
• Orographic Lifting
• Potential Temperature
• Relative Humidity
• Saturation Vapour Pressure
• Solute Effect
• Supper Saturation
• Vapour Partial Pressure
There would be alot of work requiered to do this so that clouds behaved correctly durring an animation in a cnvincing mannor.
Regards to you.
Cyber-Angel
That's a pretty comprehensive-looking list you've got there. However, I have to disagree with you on the point that all of that is necessary for realistic cloud animation. If your goal is to simulate cloud patterns exactly, then it's definitely good to have all of those parameters, but then we would have to get into chaos theory and the movements of the individual molecules - and as far as I understand chaos theory, you can't calculate an exact outcome, which will make any kind of simulation slightly inexact. I think that for hobbyist and even studio-grade work, a competent implementation of the methods described by Steve would be adequate for results that look realistic (even if they actually aren't).
All this information from the pros and the otherwise knowledgeable is really very interesting. There's some great info in there, and it's always good to have even a rough idea of the basis of an effect you 're trying to recreate. But, aren't we starting to drift from the main issue here ? We 're talking about 3D animation, digital imaging, visual effects. And in these areas, in my opinion, it's not about what is real, it's about what looks real. And that's what we should be trying to achieve.
I think the previously mentioned techniques (translating the fractal pattern in X/Z for motion, and in Y for variance), and even Steve's suggestion of splitting the approach into 3 parts, should work perfectly for that.
nick
It wouldn't just be chaos theory, you would also need Complexity Theory and also the Heisenberg uncertainty principle as well if you where going to do things properly, then again its purely academic. ;D
I am yet to see any cloud system in computer graphics even in the literature on cloud rendering that utilises all of the parameters in my last post for example most of the papers I've seen either use single light scattering or if the do use multiple scattering in their schemes then its in the forward direction only nothing I've every read has had multiple nonuniform light scattering in the forward and backwards direction. Also these schemes seem to be only based on BRDF (Bidirectional Reflectance Distribution Function) and not on the more accurate and realistic BSSRDF (Bidirectional Surface Scattering Reflectance Distribution Function) of which BRDF is an approximation and appears more in the literature than BSSRDF.
Regards to you.
Cyber-Angel
An animated entity in a CG scene doesn't particularly need to be a simulation, where emulation, trickery, and "animation" will suffice. Don't give up just because the clouds in TG2 aren't true simulations of the real thing, as many animation and VFX are simply workarounds and cheats anyway, and the result of some Eureka moments and very hard work by gifted animators.
In my other passion of ancient history there is a phrase we use a lot; "Absence of evidence is not evidence of absence." For animation and VFX I would equate that to; "Absence of a setting just means the trick hasn't been found yet." ;)
It's early days yet.
Cyber-Angel presented a fairly comprehensive list of what is required to simulate cloud development. At this point however in the CG world, computational fluid dynamics (CFD) and animation have not yet been married. Cyber-Angel is correct but I agree with old-blaggard there is a difference between a simulation and an aesthetically convincing animation of cloud movement over a period of time. As a meteorologist I long for that union, but accept the fact that, within limits, we can do a fine job with the tools at
hand.
The simulation remains for now in the realm of the super computer and much work in the U.S. (I am not familiar with the same work being done in other countries) is being done at the University of Illinois at Champaign-Urbana.
Try these links:
http://www.evl.uic.edu/EVL/SHOWCASE/wojt/storm.html (http://www.evl.uic.edu/EVL/SHOWCASE/wojt/storm.html)
http://redrock.ncsa.uiuc.edu/hvr.html (http://redrock.ncsa.uiuc.edu/hvr.html)
http://access.ncsa.uiuc.edu/Stories/supertwister/ (http://access.ncsa.uiuc.edu/Stories/supertwister/)
http://redrock.ncsa.uiuc.edu/image_opal.html (http://redrock.ncsa.uiuc.edu/image_opal.html)
http://redrock.ncsa.uiuc.edu/CMG/People/jewett/Apr19/animation/r405a.1km.mov (http://redrock.ncsa.uiuc.edu/CMG/People/jewett/Apr19/animation/r405a.1km.mov)
http://dart.ncsa.uiuc.edu/virdir/raw-material/envhydrology/atmos/vatmos.htm (http://dart.ncsa.uiuc.edu/virdir/raw-material/envhydrology/atmos/vatmos.htm)
In addition NextLimit http://www.nextlimit.com/ (http://www.nextlimit.com/) in Madrid has taken a big step towards that marriage but even they have Realflow4, CFD aimed at the animation market and XFlow for the scientific market. I have been toying the Reaflow 4 to simulate a thunderstorm, but the computational overhead is immense.
You will notice the lack of visual realism in the simulations at the links above because at this time the scientist is interested in the process not the aesthetics. Right now I am trying my best to improve my skills at animating realistic clouds for instructional and television projects.
Here are two examples of what I am trying to do:
http://www.shorstmeyer.com/movies/web_cloud1.mov (http://www.shorstmeyer.com/movies/web_cloud1.mov) 4.7mb
This is an example of scattered cumulus evolving into a stratocumulus overcast. Original size was 720 x 480 and had a city skyline overlay for a TV weather program.
http://www.shorstmeyer.com/movies/web_cloud2.mov (http://www.shorstmeyer.com/movies/web_cloud2.mov) 1.7 mb
This is an example of multiple cloud decks, each moving in different directions because of directional wind change as elevation increases (the meteorologist call this directional wind shear). This too had a city skyline overlay.
Both are aesthetically accurate but ignore CFD and therefore the cloud physics at varying scales.
Both animations were done in Lightwave with the plugin Ogo-Taiki using a variety of 3D procedural textures. The learning curve is quite steep for Ogo-Taiki. The plugin also realistically simulates atmospheric optics and can do clouds from above.
I am pleased with the cloud engine in TG2 and have found it easy to manipulate, so far I like the results and have just purchased the pre-release animation version.
-Steve Horstmeyer
I am a firm believer that art and science can happily coexist within the same nomenclature, that is to say that the physical accuracy of simulation can coexist with the aesthetic needs of the artist. Thus in an ideal world Terragen would be both aesthetically pleasing and physically accurate.
What I am getting at is that today's home computers have the computing power if not more so than the Mainframes of Twenty years ago, and when Hafnium based CPU's are available More's Law and the Law of Averages says that computers twenty years form now will be at least as powerful as a Cray X3.
What I advocate is a little out of the box type thinking I am not necessarily looking at the way things are I am looking at the way things may be when I look into a subject I look out side the area that I am looking at (Such as Physically based cloud rendering) and look into areas that relate to it, meterology etc, in other words cross discipline reading.
What bothers me is that its all well and good having pure research but its no good to people stuck in a lab if its not in software that people can get, there's nothing wrong with research which is how progress is made other wise you get stagnation.
Look the topic of this thread is moving clouds and I have in my way tried to raise things that maybe over looked and would be remiss to do so other wise. Sooner or later simulation and art will come together it will come out of the lab and into people homes, there is an opportunity to do this and it would be best that Terragen lead the way in this field.
If the issues that surround this topic are hardware related then is it so hard to work with the hardware manufacturers to resolve these issues and thus progress the industry forward?
Comfort zones are all well and good but sooner or latter you have to leave them behind and move on, this is life and another fact of life and that is "Do it first before the competition dose".
For the record I have been using terrain software since Vista (Now Vista Pro) since its Commodore Amiga days.
Regards to you.
Cyber-Angel
Cyber-Angel:
I too am a vista-pro veteran, it was my first terrain software and I still have a copy of version 4 that I occasionally use for nostalgia. I have been using it since the first PC version ( I do not remember the year, maybe 1990, but that's after you began). I used it with the Mars DEMs for a show I wrote and produced called "Space: Our Journey Begins" and did a near surface fly over of the planet, including up and over Olympus Mons and into and through Valles Marineris.
I had to bring my home PC (486 processor) into the TV station and connect it to the RAID array and for a 20 second animation at 640 x 480 it ran from Friday at 7PM until Monday at 7AM and had just finished when I arrived.
Those were the days.
However, I agree whole heartedly with you, memories are great but the only way to look is forward. Not just in a straight line, but stray from the path many fascinating encounters wre there to be found.
I too think that the gulf between science and art is artificial and the two are converging at an accelerating rate. To me the more they converge the more I like it.
-Steve Horstmeyer
Steve you mentioned (CFD),
Would a CFD model be technically correct as clouds form the coagulation of water vapor (Some times Ice) around Cloud Condensation Nuclei, I would have throat that since water vapor is water in its gaseous state that a model based on Computational Gas Dynamics following Raoult's Law for vapor pressure would be more applicable, given your experience with physical observation and meteorological data would a CGD model hold true, if not could you explain why as it would help me learn a great deal?
Regards to you.
Cyber-Angel
Wow... my weatherman from my hometown posted. Very cool! :) Err... erm, Meteorologist that is.
Cyber-Angel:
I had to think for a while to write a concise and accurate answer, so sorry for the delay in responding. The atmosphere is a fluid, a compressible one and unless terminology varies CFD in my experience refers to the flow of both compressible and incompressible fluids. In the atmosphere there is no need consider "hypervelocity" and the complications that introduces.
For atmospheric models the atmosphere can be considered incompressible for horizontal flow. We know the atmosphere is not incompressible and motion is rarely only horizontal, but considering the scale of forces and the magnitude of the velocity - the atmosphere behaves as if it is incompressible.
In the atmosphere it is vertical displacement what ever the cause, that makes weather. Even at its most vigorous vertical motion is much slower than the time it takes for the pressure of a rising or sinking parcel to adjust to the changing ambient pressure, so a parcel rising, for example in a thunderstorm updraft, is at the same pressure as the environment at the same altitude.
In general because of the number of computations involved, condensation is assumed to take place if there is sufficient moisture. The measure of that is relative humidity which indicates if the water vapor pressure is near the equilibrium value. (When the RH is 100% meteorologists often use the poorly chosen term saturation).
The composition of the particular cloud condensation nucleus of course will determine the degree vapor condenses in cloud models, but because a great deal of evidence is lacking about the mix of compositions of a population of cloud condensation nuclei, models assume that if sufficient moisture is available condensation will take place. "Sufficient" of course is a function of temperature.
The Bergeron-Findeisen process describes the water vapor environment in many clouds. In a mixed-phase cloud both water drops and ice crystals coexist. Because the equilibrium vapor pressure in the microscopic water environment is greater than the equilibrium vapor pressure in the ice environment, the random molecular motion of water vapor molecules dictate that the ice crystal will grow efficiently and the water drop evaporate. Eventually ice crystals "clump" and exceed the mass the cloud updraft can keep aloft. If clumps survive long enough and fall below the freezing level, they melt and the many resulting drops then go through the collision- coalescence process resulting in raindrops. This is not the only possibility because precipitation does fall from clouds composed completely of water and entirely of ice and as we know snow and rain are not the only two possibilities.
In atmospheric models phase change is considered in bulk, that is individual cloud condensation nuclei are not considered. If the cloud environment is below an assumed temperature the phase change is assumed to be vapor >> ice and the latent head of the phase transition is calculated. If the temperature is above an assumed value then the phase change is assumed to be vapor >> liquid
and the latent heat is calculated for that particular transition. It is much more complicated than this brief explanation.
There are many good references for cloud microphysics which treat the formation of precipitation and the Bergeron-Findeisen process. It is named for the Swedish meteorologist Tor Bergeron who proposed it and German meteorologist Walter Findeisen who helped refine the theory. Interestingly a very basic form of the theory was proposed in 1911 by German meteorologist Alfred Wegener who is now remembered for continental drift.
Here are a couple links for more information:
On Tor Bergeron
http://www.cimms.ou.edu/~schultz/papers/TorBergeron.pdf
and this one is a great summary of cloud microphysics:
http://www.met.utah.edu/class/jimsteen/ATM619/lectures/cloud_microphysics.pdf
***JDex, where in Cincinnati are you?***
-Steve Horstmeyer
stevehmeyer if you were my my weatherman I would watch the news all the time. This is a great thread. I hope to see some of these animations from you :D. It will be cool.
I love the idea of a simulation like atmosphere/cloud node, but we also have to remember that Terragen is an artistic tool. CGI is not reality, and in most cases the artists do strive to create realistic scenes, but in a sense they are not realistic at all. If any sort of simulation was implemented into Terragen2 I hope overrides are introduced to the simulation as well. I do not want to be tethered by physics when I am creating an artpiece. How annoying would it be to get a popup window stating "YOU CANNOT MOVE THE SUN, YOUR SELECTED POSITION WILL RESULT IN TIDAL WAVES AND MASS POLAR MELTING, PLEASE RECONSIDER"(edlo, 2007).
I believe the creators intended Terragen2 as a tool for CGI artists, and that has to be remembered when dealing with additions such as simulations, because an iron fist simulation will quickly take away from the fundamental uses of Terragen.
Nicely put BPauba.
I do not think there is a big chance in the near future of Terragen2 becoming a "simulation" tool and for me that is a good thing.
As one who comes from the science side of the science vs art issue here (the vs. not in any way denoting conflict but just recognizing different approaches) I would find entering a few numbers representing real-world conditions then waiting while TG2 cranked out the details, much less satisfying than exploring what the capabilities of TG2 are, and seeing where inner creativity takes me.
I find the physics of clouds and atmospheres incredibly fascinating. Reality though should never be seen as a limit but as a starting point. Just think if Gene Roddenberry was tethered to the known and proven we may have never heard "Beam me up, Scotty".
According to the great biologist/scientist/thinker J.B. S. Haldane the Universe is not only weirder than we suppose, but weirder than we CAN suppose.
Nice moody render, keep it up.
-Steve Horstmeyer
stevehmeyer Good stuff. I have never heard that quote ("the Universe is not only weirder than we suppose, but weirder than we CAN suppose. "), tis a great one. I hope I did not give off the impression that I am against any sort of developement of these simulator nodes, I would love to see that! I think my thoughts on the matter were a bit extreme, because as more variables are added more possibilties arise.I am betting that a simulator approach would greatly increase the amount of variables in the nodes. I am hoping these variables you talk of come to life in future versions of Terragen. Your links have gotten me to read more about the physics of clouds! Thanks man.
Having looked into this a little further now I have discovered the words "It is assumed that" in what I have read thus far and to me those words do not belong in science. To me it is clear that there are areas in the literature that remain unclear and until such times as new instrumentation is available for direct long term measurement of these knowledge grey areas then no model can ever be exact.
If Terragen where to have an accurate simulation model then it could be a benefit to the scientific community as you could test what is known about clouds today and see weather the current models of cloud behavior hold true to what is seen by direct observation.
This how ever would require a more detailed atmosphere model then Terragen has today for example Terragen has no air circulation model and its mountain ranges do not force air upwards which as you know results in cooling of that air.
I was thinking about clouds the other evening while watching the sun go down and thinking about using small, robotic airships that could spend weeks gathering direct data from inside clouds which could release small, biodegradable instruments to gather data, these instruments would be similar to those been developed to look at the structure of tornadoes.
I am not sure how long a literature review would take but I have come to conclusion that one is required this review would show up errors, omissions, areas of agreement and disagreement and gaps / grey areas in the current knowledge on clouds the findings should then be published and a summit held to discuss the findings, conversely this would enhance and progress the area forward into areas of investigation and develop new instrumentation to answer the remaining questions.
To me a lack of knowledge is simply not knowing what questions to ask for all knowledge begins as a question and the answer is often not what you expect.
What I do know about clouds is that we can expect to learn more about them as time goes on, it is my hope that Terragen can be used both forth art and science; overturning long held assumptions and being a lot of fun along the way.
Regards to you.
Cyber-Angel
Very interesting topic, many thanks to you all
Just a thought here since i dont have the animation version of tg2...but would it be possible to get that "variance" that others on this thread have mentioned by animating the "seed" of the cloud density shader from say frame 1 to frame 50. so over those fifty frames the cloud density morphs and we get variance. Just an idea anyway ;D
Honestly, I'm not sure if that would work. If you randomized the seed every frame, I'm sure it wouldn't, but if you incremented it by 1 or 2 every frame... anyone want to do a test?
Quote from: urban_rebellion on February 06, 2007, 08:40:46 PM
Just a thought here since i dont have the animation version of tg2...but would it be possible to get that "variance" that others on this thread have mentioned by animating the "seed" of the cloud density shader from say frame 1 to frame 50. so over those fifty frames the cloud density morphs and we get variance. Just an idea anyway ;D
From what I know the seed does not have a "progressive randomness" that follows the number line. What I mean by that is seed#1 is going to be just as different as seed#550 when compared to seed#2. I do not believe any seed is more similar to one seed then to another. So what I believe will happen if you manipulate the seed number as the frames move forward is just completely new cloud formations that will not morph into eachother. I have never tested this hypothesis out though, so please do not take my word! Just adding to the conversation :D.
I second that, the seed number is a "random" input which results in totally different cloud formations.
Quote from: urban_rebellion on February 06, 2007, 08:40:46 PM
Just a thought here since i dont have the animation version of tg2...but would it be possible to get that "variance" that others on this thread have mentioned by animating the "seed" of the cloud density shader from say frame 1 to frame 50. so over those fifty frames the cloud density morphs and we get variance. Just an idea anyway ;D
Seed provides (seemingly) random values with each integer. A Seed value of 1 will look totally different to a seed value of 2. Seed values in any 3D program are rarely animatable.
As I mentioned earlier, a new 'phase' value that will solve this trick is needed (similar to what other 3D programs have to do the same kind thing).
I think the seed values are put into the internal algorithms to help to generate (apparently) random clouds while providing the user with a way of keeping a specific cloud formation.
Rrrrrrrr! Now i am aroused! ;D My english is too limited to express how interesting all this weather stuff is to me. IMHO, weather "simulation" will be a plug-in task. I don't think it will ever be a regular part of a software like TG2, which is in my eyes an artistic tool and no "Earth Simulator". Isn't in Japan something like that?
I would love to see shaders that simulate atmospheric behaviour like Cyber-Angel and stevehmeyer described, with not too many values. For example: A particle animation system for clouds and other gaseous matter would be extremly usefull for faking tornados and other weather phenomenons. Forces like friction, velocity, wind, pressure and others should be part of it.
In the far distance i can see real weather rendering, but this is a matter of understanding the atmosphere and the weather system, as many meteorogolist claim they don't fully understand it, and number crunching power of our desktop computers. Maybe in ten to twenty years we are able to release all the horsepower for tasks like that. Until that time, we can fake everything with our artistic skills. ;D
As far as I am concerned on this issue it maybe possible to do these things sooner than we may imagine, it is likely that the trend for multi-core CPU's will continue into the foreseeable future, and it can't be long given the law of averages before we see CPU's with 100 or even more cores on the same chip, this is going to affect the way software of the future is designed and programmed.
It is a fact that even today's dual and quad core chips are in many instances not been used to the full extent of there capabilities and further more, many of the multi-threaded software titles out there only use a small amount of the capabilities of the modern chips.
Can it really be that long before we see a CPU with Petaflop or even exoflop performance? Once we see this kind of performance on home computers and providing power and chip heating can be kept to economic and sustainable levels it maybe at that time to start thinking about parallel computing on the desktop.
With computers this fast with enough memory realistic weather simulation is Terragen should not be a problem on a system with 100+ cores; maybe at that stage of home computing development you maybe able to dispense with many of the tricks and workarounds prevalent in computer graphics today.
Whats next in computing maybe by the end of this century or the middle of the twenty second century we may see the first quantum computers since these are still hypothetical at best, it is the considered opinion of this author that the author has no idea of what kind of software or indeed what software would look like for such a computer.
Regards to you.
Cyber-Angel
Quote from: Cyber-Angel on March 20, 2007, 09:15:51 PM
Whats next in computing maybe by the end of this century or the middle of the twenty second century we may see the first quantum computers since these are still hypothetical at best, it is the considered opinion of this author that the author has no idea of what kind of software or indeed what software would look like for such a computer.
For the record, quantum computers are already here: http://news.com.com/2100-1008-6159152.html
Quote from: old_blaggard on March 20, 2007, 10:05:45 PM
For the record, quantum computers are already here: http://news.com.com/2100-1008-6159152.html
Really, where can i buy it? ;)
@Cyber-Angel: Computer power isn't always a matter of sheer physical presence of multi core CPU's. When i think about the old days of the C=64, Atari and Amiga computers: What did the programmers achieve with the, compared to nowadays computers, limited power? Much of the computational power is eaten up by the system (XP or even worst Vista). Many programs are multi megabyte monsters compared to software of the early multimedia computers in the 80's and 90's. I remember a DTP software for the Amiga comes on one 720kb diskette and one diskette with extras. What i want to say with that is: Computational power ist often waisted for the system or uneconomically programmed software. The best example is Vista. XP runs on many (even older) laptops perfectly, but no go with Vista. If i could run Amigas Intuition/Workbench natively on a PC, it would run as hell! If the "inventors" of the OS's would programm in a more economic way, we would have much more power for the software we want to use. Take a look at TG2TP. It is really small compared to other landscape software and runs pretty smooth after the bug-fixes and look what is possible with this limited version. I would say, good and economic programming is an artistry which many of the programmers out there don't pay much attention to anymore. TG2TP is a positiv example.
But i am getting way too off topic here. Let's return to the clouds and how we can get them look as we want them.
He He,
I had an Amiga 500 with the standard ram configuration that came with that system and before that it was a Vic-20 so that's old, old school so yes Old_Balggard I understand what you mean. Look I happen to know more about computers then I care to admit to, but add lest your not having to type Load:/ and press play on the cassette tape drive any more.
What I was trying to get at in the way of truly dynamic, physically accurate clouds in the way that has been discussed previously in this thread would require more powerful computers then are currently available on the home consumer market, or even at professional workstation level computing which is where your more likely then not to see the kinds of system I was talking about implemented first before the technology filters down to the home market.
Yes, in the old days you had to wright clean code due to the physical hardware constraints imposed by what was state of the art technology back in the late 70's and early eighties, and more over the small percentage of the population who had and could afford to buy a computer, with the main buyers back then for what we call a PC today (To user the parlance of the day, an IBM Compatible, in reference to the Open Hardware Architecture pioneered by IBM), with business been the main buyers at this stage in computing history.
I would say IMHO that there are many demands placed on programmers today, call it a product of the commercial globalization of the software industry if you will; with the high pressure, tight release deadlines of the industry we have today maybe with the pressure to perform they just don't have the time for the artistry any more, in my view it is not that they don't want to its just there is not enough time, but I am pulling no punches about software that dose not do what its end user would expect.
I look forward to seeing what the future of both Terrgen and computing have to offer, and just for the record the feeling I had when I switched on a computer for the first time, I still have today; in other words keep the magic never lose it.
Regards to you.
Cyber-Angel ;D
Hehe, it was me RealUser not old_blaggard. But i take that as a compliment. My english seems to get better. :D
Many apologies RealUser, not like me to make slip ups like that :o
Regards to you.
Cyber-Angel
Quote from: old_blaggard on March 20, 2007, 10:05:45 PM
Quote from: Cyber-Angel on March 20, 2007, 09:15:51 PM
Whats next in computing maybe by the end of this century or the middle of the twenty second century we may see the first quantum computers since these are still hypothetical at best, it is the considered opinion of this author that the author has no idea of what kind of software or indeed what software would look like for such a computer.
For the record, quantum computers are already here: http://news.com.com/2100-1008-6159152.html
I can't wait until biological computers become powerful and widespread - then we'd be able to literally kill processes.
@DarkFire: Hehe, like in "Existenz"! http://www.imdb.com/title/tt0120907/