Houdini - pen tool?

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Could you please advise if Houdini has similar tool to the Photoshop Pen tool? Unfortunately the Curves tool is not as flexible as PS Pen tool. I need to make some sharp edges mixed with round edges and I need a control over curvature.

Pen tool is just fantastic whereas using Curve tool is a nightmare when I want to draw something that has both round and sharp edges.
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The path and pathcv nodes work well.

To get started simply put in a orthodgraphic view, tab for ‘Path Utility’ then you will be able to start laying down the ‘points’ which are the pathcv nodes.

You can adjust or change the order of the points if want to by diving into the main path utility node where at the top of the network is an object merge node named ‘points_merge’. You can also add manually additional pathcv nodes later, just making sure they are included in this nodes list - ‘points_merge’.

Adjust your lines by working with their rotation and scale parameters (of the pathcv nodes). This part takes a bit of getting used to as it isn't intuitively clear which parameter to use. Which is why I suggested starting in an orthographic view.
Edited by BabaJ - 2016年12月11日 10:00:31
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So what settings would you use to draw a curve that represents black shape like this?:


Please try to draw such shape and let me know if you have succeeded.
Edited by mikolaj64 - 2016年12月11日 11:37:54
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One way is using curvesect http://screencast.com/t/m3ozQSM47zd [screencast.com]
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To do that, you'll have to do additional steps.

First is that you will have to have pathcvs sharing the same location co-ordinates. This would be where you have the straight line ending at the start points of the curve in your image. So in this case, 2 point locations will have to share an ‘extra’ pathcv.

Where those points co-exist you will also have to dive into those nodes ( “allow editing of contents”) and adjust the values of the add nodes named ‘accel1’ and accel2'. How you set these depends on which one is representing the incoming straight line and the other othe outgoing curve.

Another thing you have to do is add ‘/points’ to the object names of the Paths ‘points_merge’ node.

Also, adding a polyspline node after the output curve node of the Paths network will allow you to smooth out the curve. A resample node will do the same.

Doing these things will allow you to do the type of shape you have asked.

Attachments:
Shape-with-pathcv-nodes.jpg (38.8 KB)

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Houdini curves are not like Adobe curves. You can't have mixed point types within a single curve AFAIK. To create your design you may need multiple curves and then join or intersect them as needed.
Using Houdini Indie 20.0
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Thank you for your help!

That's a pity that there is no pen tool
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If you do what I said, you get exactly the same thing as a pen tool.
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mikolaj
That's a pity that there is no pen tool

You can easily important that path from Photoshop/Affinity/Illustrator into Houdini.
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I can't find an “easy” way to import a path. How do you do it?

When I import a .ai file using the File node, Houdini often gets it wrong even if I take the time to write the .ai file into the Illustrator 8 format. The most reliable method I have found is to export out your Illustrator file as a 300DPI PNG file. Then use a Trace node to trace it out. Often you have to follow it up with a Hole and Resample to get something usable. But logo work is possible using this approach.
Using Houdini Indie 20.0
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I can't find an “easy” way to import a path. How do you do it?

When I import a .ai file using the File node, Houdini often gets it wrong even if I take the time to write the .ai file into the Illustrator 8 format. The most reliable method I have found is to export out your Illustrator file as a 300DPI PNG file. Then use a Trace node to trace it out. Often you have to follow it up with a Hole and Resample to get something usable. But logo work is possible using this approach.

It doesn't get it wrong - it translates it into the Houdini geometry. Which means it's important to look at the winding order for the prim normal, and, note that the bezier order is 4, which is why sharp corners have co-located points. To bevel and extrude correctly, you do have to work the normals of the file but with some practice it only takes <15min. EPS works as well as Ai8.
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It takes even less time if one just uses Houdini to do the same.

As I mentioned above all you have to do is change the add node settings in the pathcv node.

Once you do that, you can save it as a digital asset. Label 1 as positive and Label the other ( with the ‘opposite’ settings negative). In order to work the path has to go from one node with one setting to the other node with the other setting. It only has to alternate between the two too work.

Once that is done all you have to is just plop down those assets in co-location pairs, and presto you have same functionality as pen tool in illustrator. Or even make an asset that drops them down in pairs to streamline it further.


Thats what I did, and it works quick and easy.

babajaiy.org - second video is using what I am saying, driven by chops.

Although each shape seems to be moving in a mirrored fasion, none has been ‘instanced’ or mirrored. Each side has its own independant form. Each side could have had its' parameter of scale or rotation changed to be unique. I didn't do that there as I was focused on other matters I wanted to resolve.
Edited by BabaJ - 2016年12月12日 20:26:37
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@BabaJ tested the PathCV tool over the last three days and unfortunately it's all bad news. It is more rudimentary than Illustrator version 1!(from 1987!) We need to be able to drag out the tangent lines to begin with, then not create nodes for every click.

https://youtu.be/xv3xl2B6yUs?t=4m44s [youtu.be]
Edited by anon_user_37409885 - 2016年12月15日 19:00:17
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From my experience the pathcv is even better than illustrator especially if you want to place the nodes down in specific locations ( co-ordinate wise ).

I once did a design ( that needed to have the location of all the nodes in specific distance and angles from each other ), Illustrator was terrible for that. I ended up using Solidworks for all the line work and only imported it into Illustrator in order that I could do the gradients.

Of course if someone is just going to do freeform work for which most people do it's perfectly fine.

If you feel it's bad news and rudimentary I would encourage you spend some more time with it.

To me when I first started working with it, it felt like some mysterious beast…but after some time I started to see why it's structured the way it is, and the potential for it.(still haven't explored all it's possibilities).

Yeah, I saw you video link too and I understand why people would want the same point/click/and drag functionality.

But with the pathcv tool you only need the scale and rotate parameter to control the size and shape of the line coming off the point.

A couple sliders could do that. Not the same and slower than using a mouse but if one wanted to they could dig into the hdk for getting hooks into mouse events to control those parameters.

Yes, it's a bit of work, but isn't that what a good part of Houdini really is…a way to make your own tools?

But aside from ease of use…the pen tool(Illustrator) doesn't have anymore functionality than the pathcv does…in fact the pen tool has less - but not going to knock it for that ( after all its intended purpose is only 2d drawing).
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