Doing a Udemy lesson using Orient on Surface using both 2D and 3D patterns onto a surface using version 8. Every time I apply a pattern it distorts by stretching the original pattern along the right side of the surface as per attached image. I believe it should be equally balanced identical to the original. Tried several examples all the same result/
Have you tried _FlowAlongSrf?
I unrolled the isocurves of the 3D surface and rebuilt a planar network surface.
flowalongsurface.3dm (132.2 KB)
Thanks for the offer. I am trying to understand why I am getting the pronounced distortion for my image on the curved surface which is shown in the upload. Is this distortion compressed on the left and stretched on the right the only outcome in the command Orient on Surface? In the lesson provided there does not appear to be such distortion to the teacher’s model pattern. Perhaps I am missing a step or not applying a condition.
can you post your file?
Try rebuilding the target surface or a copy of it so it has more equal distribution of isoparms. Not sure if thats the solve but its worth a shot.
Here is a copy of the file. I used a different pattern and a new target surface to see if it made a difference but so far nada.
Lesson 6_2 Orient on Surface.3dm (17.4 MB)
Now that I have uploaded it I see that it is 17MB. Is that possible on an object as small as this? The surface is only about 10 inches high.
the orientOnSrf command seems indeed to have a problem. preview works fine, but when it’s applied, I can reconstruct the massive distortion. one thing to be aware of is that it’s an extrusion from a pretty strange curve. if I rebuild the curve, re extrude and redo the orientonsrf command, everything works fine:
an alternative that seems to work on your extrusion also would be splop:
hope this helps
Ben
UnrollSrfUV with Labels=Yes (UnrollSrfUV, not UnrollSrf)
Position the object in the desired position on the unrolled surface.
FlowAlongSrf
Select the object
Select the unrolled surface as the base surface. While selecting remember which edge is selected and which corner is closest.
Select the original surface in the corresponding location.
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FlowAlongSrf maps the objects from the base surface to the target surface using the location of the selected edges to index the surfaces, and using the parameterization of the base surface and target surface to loacate the elements of the object being flowed.
UnrollSrfUV preserves the parameterization. UnrollSrf does not.
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Thanks Ben that does help. I find that the distortion is considerably reduced on the right side. I have been doing some measurements from center to ends and there is a small difference is size but considerably less noticeable visually. Took a look at the splop for the first time and look forward to learning it. Next in the lessons stream is the FlowAlongSrf as mentioned below by David and I will see how that works later today. Thanks again. Tim
Thanks David this command does get me to the result we are looking for. I am still trying to figure out the best use for OrientonSrf as the Udemy lesson makes little sense using it as compared to this command.
couple of things… your surface is actually an extrusion, if you run the explode command on it once it’ll convert to a surface.
I saw the same distortions you did if I tried just on the converted surface, however if I rebuild it with 7x7 control points degree 3 it applies as expected.
my take here is that something is screwy with your base surface, a quick rebuild gets it sorted.
if you were to encounter this in the wild, making a copy of the intended target surface, then rebuilding the copy, then use that rebuilt copy to make the oriented part. Once the oriented part is created, you can delete the rebuilt copy and proceed with the original surface if that is important to your design.
I do the same thing with flow along surface, I’ll often make a proxy surface to flow onto instead of using the actual model so I can more closely control the parameterization of the surface I’m flowing onto, or get one surface instead of trying to flow across a polysurface seam (which you can’t do)
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That works a whole lot better Kyle. Up until now I believed extruding a line created a surface. Thanks for sorting through this puzzle. Great Hot Wheels BTW. Love the van.
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My understanding is converting an extrusion object to a surface object has zero effect on the shape or parameterization of the surface. The conversion changes the how the data for the object is organized, but not the geometry.
Be aware that the rebuilt surface will in general deviate from the original surface. Using it to orient the object or to flow the object may result in a gap or interference between the object and the original surface.
It is a matter of Rhino semantics. The internal data organization is different for an extrusion than for a surface, but not the shape. A few commands which work with surfaces do not recognize extrusions, though I don’t recall encountering one recently. Otherwise an extrusion behaves like a surfac or polysurface.
also extrusions are far less heavy on the data for huge files, i think somebody explained that this was the reason for it to actually exist if i can recall that correct
you can use UseExtrusions and decide what you want to happen when extruding.
and use ConvertExtrusion to convert them.
yeah, I generally do not use extrusions because, although they are lighter, they tend to behave strangely in cases like this.
the useextrustions command set to polysurfaces is how I run personally.
correct, but, but after converting it to a surface, rebuilding it with a higher, but more evenly distributed u,v count will generally speaking sort out stuff like this.
Also correct in general terms, but typically if you rebuild to a higher point count this can be managed pretty closely.
this is not correct… extrusions are their own thing… if you for instance trim one, it converts to a regular surface. They tend to be used in architecture and more specifically in blocks that are intended to be duplicated lots and lots of times… the file size savings can be quite high when used properly, but they tend to suck for regular product design modeling, and get in the way more than they help.
see below.
When correcting the work by converting the extrusion to a surface by exploding and the applying the 7 x 7 points in the rebuild of the surface I did notice that the profile of the wall had changed slightly form the original. I upped the point count to a level that it created a curve profile that was virtually identical to the original. Thanks guys.
yep, depending on your needs you can crank that up quite a bit and make it identical to within file tolerance. Most stuff like this is for decoration and has a slight “ish” factor that makes sub millimeter precision not necessary. But for sure do what works for your model and situation.
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