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RainyDaze
03-23-2014, 01:15 PM
I'm using the Lightwave 3D tutorials from Lynda.com and they're actually working out fairly well; I'm learning a lot. I am; however, having some slight technical difficulties.

For instance, Lynda.com has a tutorial that creates a simple cloth in Modeler (using a flat box). A new layer is created to make a ball. The 2 layer object is saved and exported to Layout. The tutorial ends. The very next tutorial shows how to drop the "cloth" over the ball using gravity, collision, and cloth FX to make the cloth drape over the ball.

Here's the problem: When I use the cloth and ball I created in Modeler (following their exact instructions) the cloth drapes over the ball, but it rips through the cloth; however, when I load the scene (presumably with the exact same cloth and ball) the cloth drapes over the ball with no problem. I've checked the settings for both (the one I created in Modeler and the one loaded from the exercise file) and I see NO difference. I've also tried to adjust the BOUND and FRICTION (which the tutorial said would keep objects from poking through the cloth) but even using extreme values I see NO difference.

Can anyone tell me what I'm doing wrong?

prometheus
03-23-2014, 01:41 PM
hard to say without the scenefile posted.

is the subdivision order the the same in both sceneīs?
other than that... I think some settings in the clothfx tab might not be the same...and something you missed.

Michael

prometheus
03-23-2014, 01:49 PM
cloth fx basic tab and sub structure and hold structure might be different, check that...maybe also the spring setting.

RainyDaze
03-23-2014, 01:53 PM
120948120949

I hope I did this correctly. Here are the two scene files.

RainyDaze
03-23-2014, 01:58 PM
120950

Here's the tutorial...

- - - Updated - - -

Cool. I'll check those.

RainyDaze
03-23-2014, 02:03 PM
Under Object Properties, after ADD FX and using "cloth" FX in the FX tab, I'm using the preset for cloth (thin) under the ETC tab; All the settings after I hit the preset seem to be the same.

prometheus
03-23-2014, 03:38 PM
you canīt just post scenefiles, you need to post objects too..lightwave gives error messages of missing objects otherwise.

make a main folder called something like clothfx and within that save objects to an objects folder, and scene to scenes folder.

right click and send to compressed map(zipfile) and post that.

RainyDaze
03-23-2014, 05:05 PM
120957
120958

Okay I'm trying again...I'm sorry. Thanks for being patient.

The tutorials scenes are called "SimpleClothFXBegin" and "BrickWallBegin". My scenes have the word "Test" at the end.
The tutorial objects are called "ClothFX2" and "StoneWall". My objects are called "Cover_Box" (because I first tried to duplicate the effect with a box) and "BallinWall".

RainyDaze
03-23-2014, 08:10 PM
This is getting REALLY frustrating. Nothing I create in Modeler is working in Layout the way it's supposed to. I put skelegons in a simple cylinder, saved it, and exported it to Layout. I used Cvt Skelegons, and followed the instructions to attach the bones to my cylinder, and nothing is happening.

prometheus
03-23-2014, 08:24 PM
This is getting REALLY frustrating. Nothing I create in Modeler is working in Layout the way it's supposed to. I put skelegons in a simple cylinder, saved it, and exported it to Layout. I used Cvt Skelegons, and followed the instructions to attach the bones to my cylinder, and nothing is happening.

skelegons must be in the same layer as the object when you finally send them to layout, further on..make sure you enable bone deform, in layout setup bone panel.

Michael

prometheus
03-23-2014, 08:31 PM
None of the scenes you posted has any collision object,hard fx or clothfx applied at all, so we canīt test anything with them.
donīt know why you donīt get them in there?

prometheus
03-23-2014, 08:42 PM
canīt tell anything on how you have set it up, since I donīt know what you use since all your fx isnīt with the scene.
and I havenīt checked the video tute either, but after fast testing, just raise your collision objects radius, do not let it
have a value of zero.

Michael

erikals
03-24-2014, 12:47 AM
maybe Mike's tutorial can help >
https://www.youtube.com/watch?v=qRh2Jpl4_Vk

and... >
https://www.youtube.com/watch?v=uBJ50fCRdlU

prometheus
03-24-2014, 08:50 AM
maybe Mike's tutorial can help >
https://www.youtube.com/watch?v=qRh2Jpl4_Vk

and... >
https://www.youtube.com/watch?v=uBJ50fCRdlU


yes..I recommend watching that, I do understand the issue now he had with the cloth sort of, unfortunatly I can not
really work with Lightwave properly at the moment, im running my laptop in fail safe mode since normal mode is crashing on me with some errors on either the disc or perhaps the memory, so I can only do simple test and hardly navigate with that mode on, have to be absent from the help support for a while and fix my own hardwar issues.

I will probably have to make a completly new full recovery system install if itīs only the operating system malfunctioning,I have done a backup of most a while ago, but always manually check if I need to backup some more before cleaning it all, otherwise I will have to fix another computer that just needs new harddrive.

for the clothfx issues, check the video links...and learn...I couldnīt follow the video from lynda.com..but sounds ridiculous if they havenīt forseen these issues and also demonstrated how to solve it, why not contact them?

Michael

JoePoe
03-24-2014, 10:20 AM
Yes, it's frustrating when you follow along with something exactly and don't get the same result. I think we've all been there. :)
(Like Prometheus said, the attached scenes did not come through with any dynamics.... or anything key framed for that matter, so....)

.... I followed all the steps in the video (thankfully, pretty basic stuff) with their objects and yours.
It is odd that they get such a "clean" result with those instructions, yet following along does not. I believe I got the same result as you did.... not exactly tearing, but the collision object can clearly be seen. As suggested above, there are ways to overcome the discrepancies (collision offset etc...), but your valid question still remains..... why the different results with the same settings??
To me, something is not being said in the video...... Or is barely being said. :hey:

In the video the instructor, in passing, mentions that he has the cloth object set at a default SubD level of 3 or 4. Well which is it??
Default, of course, is three, but in this situation a bump up to 4 makes all the difference in the world. SubD 4 looks much much more like their example 8~.
Another possibility (unsaid in vid) is that they are using CC SubDs..... a MUCH denser mesh making for a HUGE difference upon calculation, and, in comparison, an absolutely "clean" result. I believe CC subD 3 is equivalent to regular subD 8!!

Edit: A little more evidence supporting my theory.
Yes, I realize that they were recording and calculating at the same time. Even so....
The calculation time seems very long for LW SubD at 3. It takes them over a minute.
In comparison, my machine (while not recording, is older than dirt and limping along with hobbled processors) does it in 12 seconds. 24 seconds at LW subD 4.


side note: good luck with the computer(s) Prometheus! :goodluck:

prometheus
03-24-2014, 11:08 AM
Thanks JoePoe, I need some pushing to get my *** going to fix my computers, my desktop is even much better than my laptop which Ivé been working on for over a year, havenīt gotten around to simply change harddrives and reinstall
the desktop, I think it failed since I did a spyware scan and it removed some important files..so it chould be easy to fix ..just have to check how to install the drives properly since the case is a little awkward to open..for someone not used to do it.

Regarding clothfx and subdiv, not sure if they actually used subdivision order set to first, in such case it will calculate much slower, but also more accurate.
using a higher subdivision level is better, but it also depends on how many divisions you actually have in the mesh
for a starter, it might even be so that it is better to have it divided more times in modeler than setting the level later in layout...not sure about that though, also..it might be worth checking to triple the mesh in modeler first.

you also have collision bound offset in the cloth fx tab.

now I really canīt test this properly, I would set up my own ball and clothfx object and run it..and I think I would get
better results, I think I even posted a scene somewhere where a cloth drapes over something quite nicely as a table cloth ..I think, but in that case I am not sure I used hardfx or collision object...to bad I canīt work properly with it now..otherwise I think I could have solved it fast.

A side note, on the lightwave youtube page there is a reveal lamborghini effect, a soft body blanket removal to showcase the car, itīs bullet softbody I think, but even there some simulations might be hard to get exact, and thus they are also showcasing the external module chronosculpt, for cases like this where simulations donīt behave and you simply want to edit and correct them with a brush....extra cost for the chronosculpt module though.

Michael

RainyDaze
03-24-2014, 03:54 PM
I seriously thank ALL of you. I was worried that I was asking a seriously dumb question, but JoePoe's post made me feel..well...less dumb. Prometheus and Erikals, thanks for the ride along and the tutorial link. I will try all of your suggestions and post back the results. Thanks again to all of you.

prometheus
03-24-2014, 04:07 PM
I seriously thank ALL of you. I was worried that I was asking a seriously dumb question, but JoePoe's post made me feel..well...less dumb. Prometheus and Erikals, thanks for the ride along and the tutorial link. I will try all of your suggestions and post back the results. Thanks again to all of you.

Did you solve the issues you had with bones? and in such case what did you have to do?

RainyDaze
03-24-2014, 04:32 PM
JoePoe, It WAS the Display SubPatch Level. THANK YOU! THANK YOU! THANK YOU! It was set to 3, but I set it to 6 and the cloth performed like it was supposed to in the tutorial. Now my question is: What did I just do? Lol. What does the Display SubPatch Level actually control (for future reference)? And what are CC SubDs? Lol.

prometheus
03-24-2014, 05:04 PM
JoePoe, It WAS the Display SubPatch Level. THANK YOU! THANK YOU! THANK YOU! It was set to 3, but I set it to 6 and the cloth performed like it was supposed to in the tutorial. Now my question is: What did I just do? Lol. What does the Display SubPatch Level actually control (for future reference)? And what are CC SubDs? Lol.

subpatching is like chicken wire when you try to press it on to your face or something:)
the more divisions set, more wires/ polydivisions in are added for a better deformation, a chicken wire
with only a few wires wouldnīt deform nicely around any object, a lot of wires and it will:)

using display subpatch is sort of a parametric interactive edit function/smoothing/division function over the object, in modeler you can for instance create a plane and divide it in a couple of ways, one way is to do it by ways of no returning, that is to freeze a ubdivided object, that means you canīt go back and lower the divisions.

by hitting tab in modeler you can turn a box to a sphere, subpatching will also interpolate and smooth round areas between polyedges, if you have a box with several edge loops around the box, the box will not turn that round when using subpatching.

It takes a while to understand the different versions, if you try to raise subpatch display levels in layout on a divided grid, it wonīt work unless you have subpatched it"tab" in modeler, or use the layout toggle subpatch.

Catmull clark ..that is for someone else to explain...I think I probably may have messed up your brain about it anyway:)

http://lightwiki.com/wiki/Fundamentals_of_Subpatch_Modeling

JoePoe
03-24-2014, 06:01 PM
:D (I'll answer also.... too much confusion never hurt nobody right ;D)

Raising the SubD level in Layout is simply increasing the times each polygon in the mesh is subdivided. The higher you go the denser the mesh.

In your Lynda tut, while in Modeler you hit the Tab key for your objects. This put them in SubD mode. I'm sure they mentioned that.
But did they explain that you have two choices for the type of SubDs you would like to use. Subpatch or Catmull Clark... CC for short. Each has their pros AND cons. (I personally rarely use CC subDs.)
Without getting too in-depth right here.....very simply, CCs is a SubD method that utilizes a different mathematical process to subdivide the mesh. For one thing it allows you to model with polygons having more than four sides within a subdivided object, usually a strict no no. This feature, in thoughtful and skilled hands, can be a huge benefit. But all too often it is used as a shortcut around clean modeling and good poly flow.... but I digress. For the purposes of this conversation, CC meshes are inherently denser from the get go, so the increase in poly count for each level up rises exponentially faster then regular subDs (like I said, CC 3=Regular 8). Be careful.... in the right situation you can set regular subDs very high but trying to do it with CCs can freeze or crash you. Anyway, regardless of SubD type, try to find a level where you get just enough polys. Too many is just wasted computer computations.

For a more technical explanation I'm sure others will chime in, but just do a quick Google for Catmull Clark SubD.

Oh.... one last thing. You set the Display level only. This will only affect what you see in open GL. You have to set the Render level too for the same final output.

I'm glad it worked, but as I mentioned above, there are several ways to "make it work". The question still is.... is that, in fact, what they were doing at Lynda??

prometheus
03-24-2014, 06:30 PM
Raising the SubD level in Layout is simply increasing the times each polygon in the mesh is subdivided. The higher you go the denser the mesh.
]


a side note, it isnīt really just increasing how many divisions that is added, it also metaform/smooth interpolate the object, in modeler that is equal to subdivide/metaform, if it only were to increase divisions, it would be equal to subdivide/facet...which in fact just adds divisions on the object without performing a smoothness/round interpolation.

In layout you can simply go to layouts modeler tools, create a cube, then go to toggles subpatch..which is equal to modeler subpatch through the tab key.(which reminds me of a better consistency and change of shortcut for tab in layout of hiding floating windows to something else, and map the tab key to subpatch as it is in modeler)

Once you toogle subpatch on for that cube ..it will turn in to a rough sphere, and raising the subpatch level will make it smoother even.

Michael

JoePoe
03-24-2014, 07:27 PM
Lol. Sorry for the confusion. I meant "simply" as in "without getting to complicated about it".
I didn't mean to imply is was simple subdivision.... Yes, technically it is a metaform subdivide.

RainyDaze
03-24-2014, 08:17 PM
If you listen closely, depending on how far you live from Augusta, Ga, you can hear my mind exploding! Lol! I DO vaguely remember them saying something about CC now that you've explained it. As for the skelegons, I was able to fix that issue with some button clicking until I finally found the right configuration, but now I'm having trouble adding bones. In the tutorial, the guy has me add some simple bones to a bottle and then demonstrates how the bones won't move the object until they're activated. He activates one bone, and the object falls to the ground. He explains that activating the remaining bones will stand the object up (he activates ONE additional bone, and the object stands right up). He finishes activating the remaining bones, and the bones then control the object. After my bottle falls, it never gets back up! Lol. I activate additional bones, change layers, Enable and Disable IK, Deform, and MC (whatever those are...just a shot in the dark), and I manage to get the bottle to stand back up, but the bones STILL won't control the bottle. I finally emailed the guy...Dan Ablan (the tutorial is for LW 10)...and explained my issues. Hopefully, he'll respond. Lol.

spherical
03-24-2014, 10:36 PM
If you listen closely, depending on how far you live from Augusta, Ga, you can hear my mind exploding!

Just heard it. Took a while to get here, though. From my Location, you can see where I am.

prometheus
03-25-2014, 06:02 AM
Just heard it. Took a while to get here, though. From my Location, you can see where I am.

I donīt hear anything.....wait..what was that, I think it arrived to stockholm now:)

Regarding bones, do a magic trick and make your bones in your leg dissapear, then try and walk
on those jelly flesh legs only:)

bones are there to deform and also hold the mesh structure, canīt say anything about it other
than you do something different or they have not showed all things they should, bones might
not be rested, not positioned right etc.

Michael

prometheus
03-25-2014, 10:52 AM
For more cloth fx info...you could also check here, and see the section at the bottom at the page regarding resolution and accuracy for simulations..
http://lightwiki.com/wiki/ClothFX