I learned Rhino way back in school and then transitioned into Alias and have been using it that ever since as an Industrial designer. I work in a firm with other Alias and Rhino users and I’ve noticed over time the Rhino guys often struggle a lot more with creating perfect reflections on constrained pillowed surfaces (example: back of iphone gen 1), as well as producing constrained organic high quality surfaces quickly (automotive style aesthetics).
When asked to do the types of surfaces mentioned above the results are often a multitude of heavy surfaces with hundreds of control points and isoparms that cannot be easily edited or slightly tweaked. These surfaces are always created with some sort of curve network or bi-rail etc. Generally always a tool and often not very clean.
In Alias we will often “hand sculpt” more difficult (well almost all) organic surfaces rather than rely on tools and curve networks/rails/bends etc. By hand sculpt I mean create adjacent surfaces with the same parameterization and individually line up the control vertices to create different lvls of continuity. Another technique is to start with one simple surface, like a loft or even a plane and manipulate the control points till the desired shape is created. As a general rule of thumb many will say “you aren’t using Alias if you aren’t moving surface control vertices (cv’s)”. Meaning that if you are only creating surfaces by using tools between curves and other surfaces you are not really using the power of the software.
My question is does anyone work this way in Rhino? I’m looking for a way to help my Rhino friends speed up their CAD and gain more direct control over the sculpting of their models. Are there any good techniques for easily manipulating control points in Rhino? Alias has a few killer tools for this that I’ve seen duplicated in the Rhino plugin VSR in videos. Seems like a very pricey way to solve our problem. I’ve always assumed since Rhino is also a NURBS modeling system it would be capable of the same types of workflows as Alias but I’ve yet to see anyone use it that way. If their is a better Rhino workflow to achieving high quality (not t-splines) highly editable (simple) surfaces I’d love to learn more about it. Or is Rhino just used in a different way? All thoughts, comments and opinions welcome.
Is it? Compared to the price of Alias? --Mitch
Ok, maybe this is lame but do you know the PointsOn command (F10)? This way you can edit controlpoints in Rhino. I assume that you know it.
If your Alias workflow is hand-sculpting simple (bezier?) surfaces by individual cv manipulation, what does the control vertex manipulation of Rhino not offer? What exactly are the killer tools you need?
Another useful command for getting continuity between surfaces is MatchSrf. Merging surfaces: MergeSrf.
You can temporarily hide control points that you are not interested in with HidePt, to reduce clutter in the viewport.
Continuous continuity matching of adjacent patches with real-time display of reflections, etc…
I think you have to have worked with alias to know what he means, i myself also find Rhino really lacking in controlling surfaces, VSR is a good tool but even that isnt enough, i myself cant afford Alias or i mightve purchased it but the price is too steep for me.
I think if rhino would only get certain key aspects of surface control right, it doesnt even have to be a direct Alias competitor but just more surface control is all i would like,…
I do a lot of this and my toolset includes;
Hi Sabino- can you be more specific?
I think I’d have to show a few videos and or lots of images to really convey the tools in Alias if you are not familiar, they really arn’t construction tools just manipulation tools.
One really good example is the pivot point tool that allows for things to be scaled relative to a pivot that can be placed anywhere, another tool is slide CV, this will slide the control points along the imaginary line between the next control point maintaining continuity and providing a fast way to extend an organic surface in a pinch or adjust a blend. The ability to select entire rows of control points at once is very helpful as well in making things speedy. Another one is what some people call the “bubble” tool it will move the cv’s directly outward or inward in the vector of the normal of the surface.
While Alias has some cool tools, its not really the tools, I can manually duplicate the effects in Rhino using construction curves to guide the snaps of the control points and stuff like that. I can rebuild the surfaces to all be degree 5 single span etc. but its seem very slow (i’m not a rhino expert by any means).
Thanks for the tool list Marc, I will ask my buddies about those tools.
I think my reason for the curiosity is that The Rhino guys I work with at least don’t have the same understanding of how to construct high quality simple surfaces, and I’m wondering is that because its easy to use the Rhino tools as a crutch to get a decent result (like curv network) or is it really not good at it and or can high quality surfaces be achieved without parametertization using tool settings and control alone w/o manual control point manipulation once a surface is created?
When giving advise on construction of lets say a pillowed iphone style back after seeing some sloppy attempts with a single blend between a flat rear surface and a single outline polycurve, I will suggest trying to build each section individually. A separate curves for the edges and the corners, both with the same degree and spans (maybe 5 1 or 2 span). By using match surface and then finally doing some slight control point manipulation the results can be achieved but it takes a while.
Is there a good tutorial or better way to create this type of surface in rhino? I’ve also suggested they start from a sphere in some instances for more spherical organic shapes and only use control point manipulation to achieve the base shape. This works fantastically in Alias but I find in Rhino its get sloppy fast. Does anyone work this way?
In Rhino, enable DragMode=ControlPolygon for this.
Right- - there is SelU and SelV in Rhino- you can see which is which when points are on by the little red (U) or green(V) lines attached to the surface points. If you select one point and SelU or SelV, you get the entire row. I understand that this is not as quick or fluid as clicking on a control point polygon (hull) segment, but it may help.
Oddly enough, just yesterday I made a quick and dirty tool for this, called LoftCrown - it is admittedly a hack to see if the functionality is about correct, See the attached plug-in for V5 SR 9 or later - drag and drop to add the command LoftCrown. Again, it is a very quick trial, it does not do 100% of what I think you are after but it might be on the right track.
In general, I ‘get’ your comments - it is not the first time we hear this- thanks for the feedback.
LoftCrown.rhp (9 KB)
Gumball can do this…
MoveUVN or Dragmode set to UVN will do this…
I’ve used the gumball feature before I think in the past where is it?
Gumball is set in the ‘status bar’ at the bottom of the screen. There are several gumball related commands on buttons in the ‘New in V5’ toolbar. Gumball location is saved for individual objects but not for multiple selections.
[quote=“elldawg99, post:8, topic:13991, full:true”]
One really good example is the pivot point tool that allows for things to be scaled relative to a pivot that can be placed anywhere[/quote]
Is this fundamentally different than using Scale in Rhino with the selected “origin point” equivalent to the “pivot point”?
Thanks for the tool suggestions I will sit with the team and see what they make of them. I have a feeling they just aren’t using the software to its full potential.
Does anyone know any good control point manipulation tutorials or “Class A” (hate that term) Rhino videos I could watch to get a better idea of these types of workflow?
My co-worker said this about control point modeling recently when I showed them some VSR plugin videos;
“I haven’t done too much CV editing in Rhino, mainly because of the limitations. Most of the time if you modify CV’s in Rhino you break that surface’s continuity to its surrounding surfaces. So tweaking a surface sends a chain reaction through your model. Or you end up building it from scratch using a network of lines (which you can modify, but have to rebuild the surface each time you modify).”
To me it sounds like if he used some of the tools suggested above it might be easier, and or used some guide lines to snap control points to so continuity isn’t lost.
I mean honestly the same thing happens in Alias if you don’t understand how to maintain continuity through control points, its not magic software or anything it doesn’t even have a fully functional undo feature, just has a nice UI, displays more realtime information about the surfaces, and construction history is probably the most valuable feature if you want to spend less time between concept iterations.
I think its similar but Rhino will forget that point right after the operation. I suppose you could set up lots of guides though.
Yeah - the DragMode > ControlPolygon can help a lot - one nice little trick for DragMode is that you can add a macro
to a shortcut or alias, and then use the same alias and it will set it back to normal CPlane mode - that is, selecting DragMode with the same option twice in a row resets it to default, so a shortcut can act as a toggle. I use this all the time.
Nice tip Pascal. It makes ControlPolygon a much easier call. One question though - if you’ve matched two adjacent curves or surfaces to G2, then edit the point structure using DragMode > ControlPolygon, is there any way that you can maintain anything more than G1? Or do you have to resort to EndBulge for this to happen?
Correct - it helps for maintaining tangency only, but it is still handy for moving the third row in a controlled way to keep things aligned so that matching the surface may make a minimal change.
i use rhino like that.
control point manuplation is my daily basis.
i generally create a surface (with minimum control points) bigger than adjacent ones then trim the unneeded parts. rather than using the trim edge.
some times on purpose i create same degree span surfaces so that i can change control points at the same time.
and what tools i use
-sweep1-2 (if the input curves are neat result may be what you seek)
-split isocurve (detach i guess)
-match surface (align)
-shrink (trim convert)
-object intersection (it has history so helps to see the result before trimming, also curvature graph for intersection curve updates)
-show edge (for naked ones)
Thanks for the tips and tool list!