# I wish there was a better way to draw curves with the pencil

**URL:** <https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788>\
**Category:** iRhino 3D\
**Tags:** windows\
**Created:** [October 26, 2024, 12:26am UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788 "2024-10-26T00:26:56Z")\
**Posts on this page:** 20\
**Page:** 1

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**Author:** ![doubletrouble](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/doubletrouble/32/773004_2.png) [@doubletrouble](https://discourse.mcneel.com/u/doubletrouble)\
**Post date:** [October 26, 2024, 12:26am UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/1 "2024-10-26T00:26:56Z")

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Perhaps I’ve missed something, but I’d like to be able to sketch out curves (preferably w. some smoothing) that I can then

1. tweak the control points if necessary
2. use these curves to make extrusions, lofts, sweeps etc.

Markup tool can be extruded but has a bunch of limitations  
Making a spline from scratch is possible but tedious and hard to see (zoom window was a great addition though)

Now if I want to adjust control points in order to close a spline f.e. it’s impossible because as soon as I use the pencil it begins a new markup instead… finger’s don’t do a whole lot either.

I have such high hopes for this app but it’s so hard to use at the moment.

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**Author:** ![encephalon](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/encephalon/32/611970_2.png) [@encephalon](https://discourse.mcneel.com/u/encephalon)\
**Post date:** [October 26, 2024, 7:16am UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/2 "2024-10-26T07:16:11Z")

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the command is called Sketch, it also works in iRhino and works with a pen.

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**Author:** ![mkarimi](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mkarimi/32/764570_2.png) [@mkarimi](https://discourse.mcneel.com/u/mkarimi)\
**Post date:** [October 28, 2024, 4:27pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/3 "2024-10-28T16:27:21Z")

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Are you using the WIP version? We have a command line and some other features in the WIP version you can use

> [@iRhino3D WIP is now available via Testflight](https://discourse.mcneel.com/t/irhino3d-wip-is-now-available-via-testflight/152005/19):
>
> [Testflight](https://testflight.apple.com/join/t1a17W2T) is what we use to provide WIP versions of iRhino with new features that are being worked on before they are introduced into the official iRhino app. WIP releases of iRhino3D via Testflight contain some features that are not completely finished. For a stable release download iRhino3D from the AppStore. iRhino3D WIP ( 8.13.24278 (11.2.1) - October 5, 2024) is now available via [Testflight](https://testflight.apple.com/join/t1a17W2T) Features Added: [RV-1228](https://mcneel.myjetbrains.com/youtrack/issue/RV-1228) Finetune point input [RV-1234](https://mcneel.myjetbrains.com/youtrack/issue/RV-1234) Finetune distance between points in com…

> [@doubletrouble](#):
>
> - tweak the control points if necessary
> - use these curves to make extrusions, lofts, sweeps etc.

You should be a able to select the control point and drag it by itself or using gumball

Let me know if you’re still having issues using the WIP

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**Author:** ![doubletrouble](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/doubletrouble/32/773004_2.png) [@doubletrouble](https://discourse.mcneel.com/u/doubletrouble)\
**Post date:** [October 28, 2024, 4:57pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/4 "2024-10-28T16:57:30Z")

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I could’ve sworn that this command didn’t exist last time I tried it. It is a while though. But yeah, this is more what I meant. 🙂

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**Author:** ![doubletrouble](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/doubletrouble/32/773004_2.png) [@doubletrouble](https://discourse.mcneel.com/u/doubletrouble)\
**Post date:** [October 28, 2024, 4:57pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/5 "2024-10-28T16:57:36Z")

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I would love to see some more work towards better pencil experience. I use Shapr3d on my iPad and it works so sweet both in terms of user experience, UI and pencil integration.  
It does however completely lack any surface modeling tools. Which is where Rhino shines and for me where iRhino really would become a useful tool

I sometimes use Onshape on the ipad as well but in terms of user experience on the ipad it’s slow and tedious to work with.

Another issue I have is that most of the icons are missing, I only get icons for a few of the commands that I’ve pinned, the rest has question marks.

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**Author:** ![mkarimi](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mkarimi/32/764570_2.png) [@mkarimi](https://discourse.mcneel.com/u/mkarimi)\
**Post date:** [October 28, 2024, 5:15pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/6 "2024-10-28T17:15:25Z")

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> [@doubletrouble](#):
>
> I would love to see some more work towards better pencil experience.

Keep in mind the WIP stuff are indeed work in progress, can you give me an example of what you’re trying to do and what doesn’t work when using the pencil?

> [@doubletrouble](#):
>
> Another issue I have is that most of the icons are missing, I only get icons for a few of the commands that I’ve pinned, the rest has question marks.

Can you list them so we can add them to this list: [RV-1219](https://mcneel.myjetbrains.com/youtrack/issue/RV-1219) Missing toolbar icons

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<div class="post-metadata">

**Author:** ![doubletrouble](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/doubletrouble/32/773004_2.png) [@doubletrouble](https://discourse.mcneel.com/u/doubletrouble)\
**Post date:** [October 28, 2024, 6:15pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/7 "2024-10-28T18:15:33Z")

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Sure thing, totally get that it’s WIP. I really mean it as constructive criticism

It’s easier to show than try and explain in text. It’s mostly that it doesn’t feel intuitive.  
Drawing in Shapr3d is very intuitive, it’s super easy both making lines and arcs with the pencil.  
If you get a line or a arc depends on how the pencil is moved.  
Splines are made by drawing regularly and pushing down a little harder every time you want to add a controlpoint.

Here’s a few examples on what it looks like.

[![](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/4/4/e/44eec307b33deaad05a3a3bab837339eb43c2ed5.jpeg "3D Modeling a Bench on iPad | Shapr3D Step-by-Step") ](https://www.youtube.com/watch?v=qiIV9sE1J9w)

[![](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/e/4/4/e449509b8c9b656dd91bdf4648ba14dffa1e746f.jpeg "3D Modelling on the iPad with Shapr3D | Is it WORTH the cost?") ](https://www.youtube.com/watch?v=zZuuCOGpCgs)

[![](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/c/6/7/c676159bc8d9cbc0978d4c87eb02606428a9e6b2.jpeg "How to make a 3D MODEL using SHAPR3D on the IPAD - Architectural Visualization") ](https://www.youtube.com/watch?v=PUZZ4HwCRo8)

When it comes to modeling in Shapr, some of the sweet stuff is thanks to the parasolid kernel and might be harder to implement. Like selecting an edge and depending on which way pencil is pulled you either get a fillet or chamfer. And with the size updating in realtime makes it super intuitive.

I started to write a long list of commands down, but while doing it I noticed that many of the commands without icons all had “!\_” in front of them, and that was the reason they didnt have icons. Re-pinning them gave me them without the prefix and solved most of them!

But some still missing are  
**Rebuild.**  
**Box \_Center** Not sure if this applies to more sub-commands or not  
**Grid** I think this needs a toggle somewhere in the UI. 1st thing I do is turn it off since it’s hard to do anything w curves because theyre invisible against the grid  
**Circle** doesnt exist in the list either ?  
**InsertEdge**

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<div class="post-metadata">

**Author:** ![mkarimi](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mkarimi/32/764570_2.png) [@mkarimi](https://discourse.mcneel.com/u/mkarimi)\
**Post date:** [October 28, 2024, 6:30pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/8 "2024-10-28T18:30:50Z")

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A lot of what I see here has to do with constraint based modeling which is not a paradigm we have yet in Rhino. @Joshua_Kennedy has done some interesting experiments with constraints and I’m hoping we can get that project into iRhino at some point.

> [@doubletrouble](#):
>
> I noticed that many of the commands without icons all had “!\_” in front of them, and that was the reason they didnt have icons

I think we can be smarter about that. I’ll add it to the list  
[RV-1287](https://mcneel.myjetbrains.com/youtrack/issue/RV-1287) Command icons for command starting with !\_

> [@doubletrouble](#):
>
> **Box \_Center** Not sure if this applies to more sub-commands or not

This will be interpreted as a macro, and right now I’m not showing an icon for macros. just abbreviations.

> [@doubletrouble](#):
>
> **Circle** doesnt exist in the list either ?

Circle and many other commands don’t exist because they’re written in .net

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**Author:** ![doubletrouble](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/doubletrouble/32/773004_2.png) [@doubletrouble](https://discourse.mcneel.com/u/doubletrouble)\
**Post date:** [October 28, 2024, 6:48pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/9 "2024-10-28T18:48:26Z")

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Yeah never mind the constraints etc. Although I agree it’s on the wishlist.  
I mainly meant to show how the pencil is used when sketching and how fluid and intuitive it is.

Ah okay, Are the .net based commands never gonna work on iOS?

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**Author:** ![mkarimi](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mkarimi/32/764570_2.png) [@mkarimi](https://discourse.mcneel.com/u/mkarimi)\
**Post date:** [October 28, 2024, 10:46pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/10 "2024-10-28T22:46:32Z")

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> [@doubletrouble](#):
>
> Ah okay, Are the .net based commands never gonna work on iOS?

They will be, we’re working on it

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**Author:** ![encephalon](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/encephalon/32/611970_2.png) [@encephalon](https://discourse.mcneel.com/u/encephalon)\
**Post date:** [October 29, 2024, 8:56am UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/11 "2024-10-29T08:56:44Z")

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> [@mkarimi](#):
>
> .net

is that the reason why BlendSrf does not exist? also, will raytraced show up in irhino at some point?

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**Author:** ![mkarimi](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mkarimi/32/764570_2.png) [@mkarimi](https://discourse.mcneel.com/u/mkarimi)\
**Post date:** [October 29, 2024, 3:35pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/12 "2024-10-29T15:35:40Z")

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> [@encephalon](#):
>
> is that the reason why BlendSrf does not exist

Right.

> [@encephalon](#):
>
> will raytraced show up in irhino at some point?

Not anytime soon

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**Author:** ![mkarimi](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mkarimi/32/764570_2.png) [@mkarimi](https://discourse.mcneel.com/u/mkarimi)\
**Post date:** [October 29, 2024, 11:42pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/13 "2024-10-29T23:42:20Z")

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> [@doubletrouble](#):
>
> I noticed that many of the commands without icons all had “!\_” in front of them, and that was the reason they didnt have icons

This should be fixed in the current build. I believe you had pinned your commands in an earlier version which wasn’t sanitizing the input.  
[RV-1287](https://mcneel.myjetbrains.com/youtrack/issue/RV-1287) Command icons for command starting with !\_

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**Author:** ![hanscad](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/hanscad/32/620415_2.png) [@hanscad](https://discourse.mcneel.com/u/hanscad)\
**Post date:** [March 5, 2025, 5:11pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/14 "2025-03-05T17:11:41Z")

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Hi @mkarimi I have a wish that I believe is related to this thread.

I design organic shaped objects with openings on them (helmets), and if we could draw with the pencil directly upon the the outside surfaces of the main object with the pencil then it would make designing the openings for these objects much easier.

I’m envisioning something like Sketch on Mesh, but maybe with more smoothing and/or a specificied number of control points.

To the designer, it would be like sketching in 2D, but then the sketch would be projected to the mesh (I suppose projection would be another way to do it). Being able to work directly with a polysurf or a SubD as the main surface(s) one is drawing on would be even better, but I’m not picky on this point.

Thank you!

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**Author:** ![mkarimi](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mkarimi/32/764570_2.png) [@mkarimi](https://discourse.mcneel.com/u/mkarimi)\
**Post date:** [March 5, 2025, 7:01pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/15 "2025-03-05T19:01:35Z")

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I had a similar thought a while ago but didn’t get much traction. I’m happy to revisit it.  
[RV-1006](https://mcneel.myjetbrains.com/youtrack/issue/RV-1006) Stencil workflow with pushpull

This macro is a good starting point. You can replace `_Curve` with `_Rectangle` , `_Polyline` or another command. Not sure how well it works in iRhino, but we can refine the wrkflow based on your feedback

`! _Cplane _View _Curve _Multipause _Enter _SelLast _Project _Direction=_View _SelAll _Enter _SelNone _PushPull _Multipause _Cplane _Undo`

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**Author:** ![hanscad](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/hanscad/32/620415_2.png) [@hanscad](https://discourse.mcneel.com/u/hanscad)\
**Post date:** [March 6, 2025, 2:45pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/16 "2025-03-06T14:45:54Z")

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Ok yes, thank you, I see what you did there. I’m going to play around with this a little bit.

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**Author:** ![hanscad](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/hanscad/32/620415_2.png) [@hanscad](https://discourse.mcneel.com/u/hanscad)\
**Post date:** [March 6, 2025, 4:01pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/17 "2025-03-06T16:01:27Z")

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Here’s what I came up with, and it’s actually pretty usable as-is tbh.

I’m assuming a Y-Z symmetry plane, and I quite like the ability to have history turned on. I changed it to use InterpCrv, but I’ll make a button with each freeform drawing style. Yellow curves in the image below are the drawn curves.

! \_Cplane \_View \_InterpCrv \_Multipause \_Enter \_Project \_SelLast Enter \_SelPolySrf \_Direction=\_View \_Enter \_Mirror 3Point w0 w0,1,0 w0,0,1 \_SelLast \_Enter

I’ll bring this to my team, and see what they thoughts they have.

I would love the ability to draw and project in Perspective, and to only project to a front face.  
I could see the designers wanting more of a sketch (rather than choose points) type of drawing mode. They’ll probably also want to be able to average out several pencil strokes, etc…

My vision isn’t so much being able to draw out final geometry, although some will, this is mostly for doing layout type work afaic.

Thanks!

 ![image](https://global.discourse-cdn.com/mcneel/uploads/default/original/4X/1/c/c/1ccc662840349a528a2aacbf48bdb13b0056e433.jpeg)

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**Author:** ![mkarimi](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/mkarimi/32/764570_2.png) [@mkarimi](https://discourse.mcneel.com/u/mkarimi)\
**Post date:** [March 6, 2025, 7:55pm UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/18 "2025-03-06T19:55:51Z")

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> [@hanscad](#):
>
> I could see the designers wanting more of a sketch

Have you tried `Sketch` command with `OnSurface` option enabled?

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**Author:** ![hanscad](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/hanscad/32/620415_2.png) [@hanscad](https://discourse.mcneel.com/u/hanscad)\
**Post date:** [March 7, 2025, 2:04am UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/19 "2025-03-07T02:04:06Z")

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I have tried Sketch, but it’s pretty hard to get clean curves out of. I’m generally looking to create a single nurbs span per gesture, if that makes sense.

So I’m only choosing 2, 3,or 4 points to create the curves, depending upon if I want a straight line or a curve basically.

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**Author:** ![ftzuk](https://sea3.discourse-cdn.com/mcneel/user_avatar/discourse.mcneel.com/ftzuk/32/689170_2.png) [@ftzuk](https://discourse.mcneel.com/u/ftzuk)\
**Post date:** [March 7, 2025, 7:43am UTC](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788/20 "2025-03-07T07:43:06Z")

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You can just sketch directly onto a mesh or surface…

[Next page](https://discourse.mcneel.com/t/i-wish-there-was-a-better-way-to-draw-curves-with-the-pencil/193788.md?page=2)