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Philbert
12-12-2012, 07:11 PM
I was wondering if anyone knew of a Modeler plugin that could check the thickness of your model. Like for printing purposes, if you had an area that was thinner than say, 1mm, those points could be colored differently like a weightmap is. This way you could easily select those points and use tools like Point Normal Move to add thickness.

hrgiger
12-12-2012, 08:24 PM
I don't know if you use LWCAD Phil but that sounds like a good feature request for Viktor.

Philbert
12-12-2012, 08:25 PM
I do have LWCad, though I haven't been able to upgrade, I'm still on v3.62.

regular
12-12-2012, 08:40 PM
Read an article that addresses a procedure to check thickness of a model meant for 3D printing.

http://www.3dartistonline.com/news/2011/12/how-to-make-a-model-for-3d-printing/

Philbert
12-12-2012, 08:42 PM
Thanks, my idea actually came from the printing site Sculpteo.com, they have a checker on their site. I just thought it would be easier to have it right in LightWave so that you didn't have to jump back and forth between programs

Sculpteo's version:

http://content.screencast.com/users/philnolan3d/folders/Jing/media/fbf5cfea-076d-487c-b5f8-8a07c39668b1/2012-12-12_2240.png

adk
12-12-2012, 09:55 PM
This sort of setup might do what you need, tho not for all occasions I imagine (as shown in the gif).

adk.

Philbert
12-12-2012, 10:47 PM
Hmm. I'm terrible with nodes. Would this allow you to enter a specific size?

adk
12-12-2012, 10:57 PM
Hmm. I'm terrible with nodes. Would this allow you to enter a specific size?

Yup ... the positions of the keys in the gradient correspond to meters in this case. You can also stair-step your keys so you don't get a gradient but discreet colours. I used a similar setup for a court case to analyze differences in height between two mounds of earth (a before and after) - I sure hope that it's correct as getting it wrong would mean ... a lot of headaches for me :D

Philbert
12-12-2012, 11:58 PM
Is it easy enough to explain how to change the measurement unit, like from your meters to millimeters? It would still mean a little jumping back and forth since this wouldn't show in Modeler, but it's not so bad since the hub handles it for you.

erikals
12-13-2012, 04:18 AM
hm, nice challenge :]

not sure if sigma could be good for something...
putting an illuminated wall inside the hollow object and using radiosity might work...

http://forums.newtek.com/showthread.php?114462-translucent-plastic-problem&p=1096576&viewfull=1#post1096576

http://forums.newtek.com/attachment.php?attachmentid=91498&stc=1&d=1294094574

Wade
12-13-2012, 08:05 AM
You can set up a surface with a thickness gradient, but I think that works from the cameras point of view. Color / Layer type - Gradient - input parameter - Surface Thickness.


http://www.imagecommunications.de/tutorials/surfacethickness.html

Philbert
12-13-2012, 11:58 AM
I could've used that tutorial for my recent iced tea scene. :)

adk
12-13-2012, 12:11 PM
Is it easy enough to explain how to change the measurement unit, like from your meters to millimeters? It would still mean a little jumping back and forth since this wouldn't show in Modeler, but it's not so bad since the hub handles it for you.

The whole node flow is quite simple in this case Phil. What you're basically doing is getting the mesh's smoothed surface normals & flipping them (that's what the multiply node does with -1 in all x/y/z directions), then you're tracing a ray from each spot on the surface, in the direction of these flipped normals ( which now point inside the mesh ) & analyzing the length of these rays. The result of this is then plugged into the gradient which gives you quite precise analysis.

If you need mm instead of meters all you need to do simply add a scalar multiply node (and multiply it by 1000) before plugging into the gradient.

If you post a small object example of what you have in mind to measure I'd be happy to set this all up for you mate. What version of LW you on btw ?

PS: I think you'd need a specific plugin for this to work inside of modeler. Layout is your best friend in this case I'm afraid.

Philbert
12-13-2012, 03:26 PM
Thanks. I'm on 11.0.3 (x64). I made a test object that you can play with too. Just a cylinder with several different thicknesses. I'll try out the flow. I'm not sure I need it right now anymore but for any future printing jobs I or anyone else have it would be useful.

Wade
12-13-2012, 04:10 PM
109810109809109805

Just useing the gradient settings and ortho camera.

Philbert
12-13-2012, 04:41 PM
Wade: Is that just showing distance from camera? For these purposes you would really have to look all around the model and see it from all angles.

adk: I tried your node flow (plus the Scalar Multiply x1000) and all I have is a solid red. Perhaps I'm doing something wrong. BTW I had to do some searching to find that Advanced RayTrace. Finally found it as part of a collection on db&w.

adk
12-13-2012, 05:05 PM
Here it is with the node setup Phil.

The keys in the gradient are set up at ...

Red = 0.0
Yellow = 0.6
Green = 2.0
Pink = 6.0
Blue = 10.0

Multiplied by 1000 as mentioned previously to bring them to the mm range.

Also including a grab of the issues you might have with such a setup. You need to remember that this relies on the way that the polygon normals are pointing & the distance along that normal to the next surface "hit"

It also picks up your scale as having no thickness ! :)

PS: Ooops forgot the scene file.

adk
12-13-2012, 05:12 PM
Wade: Is that just showing distance from camera? For these purposes you would really have to look all around the model and see it from all angles.

adk: I tried your node flow (plus the Scalar Multiply x1000) and all I have is a solid red. Perhaps I'm doing something wrong. BTW I had to do some searching to find that Advanced RayTrace. Finally found it as part of a collection on db&w.


Sorry about that extra unspecified node ... you'll find the standard Ray Trace node has almost the same functionality as the Advanced RayTrace node. The latter just has some extra bells & whistles that are very handy.

adk
12-13-2012, 05:58 PM
:d

Philbert
12-13-2012, 06:03 PM
Ohh I see the problem I had the added Multiply before the Ray Trace. It should go after it. Got it now, thanks!

erikals
12-13-2012, 07:03 PM
not quite the same, but come to think of it you could use DPont boolean to slice the object in half,
then rotate the main object to check the thickness... (might work in VPR too...)

Wade
12-13-2012, 08:03 PM
109815
Wade: Is that just showing distance from camera? For these purposes you would really have to look all around the model and see it from all angles.

adk: I tried your node flow (plus the Scalar Multiply x1000) and all I have is a solid red. Perhaps I'm doing something wrong. BTW I had to do some searching to find that Advanced RayTrace. Finally found it as part of a collection on db&w.

It is the true thickness of the object - poly to poly but as viewed from the camera cutting through one ploy to the other. By using the ortho camera you can get a true thickness of the object.

Philbert
12-13-2012, 08:34 PM
@Wade I tested this now too and while it sort of works I don't think it would work well for rotating around the object.

Philbert
12-13-2012, 09:49 PM
OK great Looks like it's all sorted. Here's a test showing a model that I've already had printed, in fact I use it every day. I changed the colors to a warm / cold scale. Red areas are the thinnest, potential problem areas, and dark blue are thickest, no problem at all. I'll also attach the surface file.

BTW on a side note I've found that for both Shapeways and Sculpteo you have to scale your model up 4000% and face it down -Y before saving as OBJ and sending to them.

Wade
12-14-2012, 11:07 AM
This is great stuff, maybe not needed by many or often but it very much shows how deep Lightwave is. Newtek should add a preset category for surfaces like this called "tools" or some such thing. This surface node goes well beyond just a surface as becomes a useful tool. Who knows given a little promotion it by itself might sell a copy or two of LW. 2-cents....