HDK : Houdini Development Kit Latest Topics

How to put my asset in the right section in tab menu?

Wed, 16 Apr 2025 15:50:56 +0000

Hey, everybody. I've created my own assembly. I put the dll in the dso folder. Houdini sees it. But when I use it, the tab menu shows it in the Custom section
How can I make it to be in the section I need?
Let's say Tab -> My Assets -> test asset.
Can you tell me what I need to do, is there any information on this issue?

How to properly implement data persistence when copying or cloning a node?

Tue, 18 Mar 2025 19:35:44 +0000

Hey, everybody. Wrote a sop node functionality that loads geometry data from an external file. I have encountered several problems:
1. All data is lost when the focus is lost from the node - this moment was solved by caching the data and then restoring it.
2. Copying a node via ctrl-C/ctrl-V or via drag + alt - I haven't solved this problem yet.
Could you tell me how to realize this correctly? Unfortunately, I am still new to HDK and couldn't figure it out or find an example in the documentation.
I would be glad to have any help from the community!
Thank you all in advance!

tbb::task deprecation problems with Hcustom

Mon, 27 May 2024 11:06:32 +0000

Hi there,

I just tried to use Hcustom to compile one of the very simple samples from the HDK docs, and I am getting an error regarding a missing "task" within "tbb" as you can see in the screenshot below, I think side fx moved from TBB to oneTBB, anyone having this issue who can give me a hand on how to resolve it? noob HDK user here.

Visual Studio 2022 and HDK

Sat, 16 Mar 2024 14:52:36 +0000

As you know Houdini HDK works with Visual Studio 2019, But I have 2022.

If you want to use CMake Project with 2019 config you have to install a specific toolchain of 2019 ( VC 142 and Windows SDK 10.0.18362 ).

OK, I Installed them but I got this error in Cmake GUI, it says: can't find the instance of Visual Studio 2019.

What should I do to fix that?

When compiling houdini HDK with CMake, it was Unable to open the include file？

Thu, 13 Jul 2023 04:07:09 +0000

I tried to recompile the source code of the ROP_FBX node in Houdini, but I encountered an issue with missing FBX source files. I'm wondering if anyone knows what the problem might be.

Is it possible to create a UI like a python panel with hdk?

Fri, 20 Jan 2023 07:55:43 +0000

How can I make a UI with hdk...?

HDK Nearest point

Wed, 22 Aug 2018 06:49:01 +0000

Hello, I started learning hdk.
I need to find a nearest point, what the best way to do this? I have an example code in attachments. But it doesn't work as expected.
Thanks

sandDunes.cpp

sandDunes.h

Custom Qt widgets

Sat, 02 Jul 2016 12:39:50 +0000

Hi guys,

Is it possible to use custom Qt widgets for node parameters instead of the predefined look you get from parameter templates?

Also is there a way to use Qt widget for a pop up directly without using ui scripts?

Cheers, Mila.

How to check for attribute by name and owner?

Sun, 10 Sep 2023 00:05:53 +0000

Since the GEO_Detail::get*Attribute functions all seem to be deprecated, how can i check to see if an attribute exists from name and owner alone? Im reading in external data and want to be able to check if an attribute has already been created based on its name and attribute owner not a GA_Attribute. The only way i see now is to use the AttributeDict iterator. Thank you.

Examples of the UT_JSON* classes?

Tue, 11 Jul 2023 02:51:45 +0000

Hello,

I am trying to create a IOTranslator for a file based in json format but have been at a loss to understand how to use the UT_JSON* classes to read this data. Since theres a bit that i don't understand i was hoping someone knew of some examples using them rather than me asking a very long, beginner question.

HDK: Dynamically update-able dropdown menu PARM ?

Sun, 26 Sep 2021 04:24:26 +0000

I would like to add a parameter which I will can fill in with information from geometry files I load ?

What kind of PARM should I design it with that will allow me to dynamically add items and also register some call back so that I know what options the user have chosen ?

HDK: File chooser - only certain extensions ?

Sat, 25 Sep 2021 18:30:15 +0000

I would like my file chooser in my C++ SOP plugin to only show up certain file extensions.

What is the recommended way ?

fastConsolidatePoints() deprecated since H17.5

Wed, 03 Apr 2019 21:00:21 +0000

It seems that all point consolidation methods pre H17.5 are deprecated and we should switch to using GU_Snap instead. Problem is, there is no GU_Snap in H17.5 or at least I couldn't find it.
It's not a separate file in $HFS/toolkit/include/GU directory and it's not embedded inside any header file in whole $HFS/toolkit/include directory.

Is it not included yet in builds?

Any help?

GU_Intersect wrong normal

Thu, 08 Sep 2022 10:28:08 +0000

Hello,

I am computing intersections using `GU_intersect` class. It has an interface that implies that it should be computing interpolated normal. I've got my scene setup with both point and vertex normals set. However, no matter which part of the geometry the ray hits, I always get primitive normal (which isn't even set). I am accessing the normal using `GU_RayInfo::mNml`.

I've even tried evaluating normals of the primitive using UVs, but the results are the same regardless UV values.`rayInfo.myPrim->evaluateNormalVector(normalOut,u,v)`

How can I get interpolated normal without having to compute it manually?

why SDK C++ in the first place?

Fri, 04 Mar 2022 16:05:14 +0000

hey guys, this is a silly question for some of you I know I am a C++ programmer in the first place and I use Houdini as an Artist, however, it's been like 6 years now and I can do almost every thing in either vex and python (my job is to create FX using existing solvers). Can you give me some use-cases where someone needs to write C++ code? The only use-case in mind is integrating with third party applications (e.g. data translators), are there any other use-cases?

Thx

City Engine Palladio

Sat, 28 May 2022 14:05:28 +0000

Hi, Is there anyone who installed Palladio Plug-in successfully? I am trying to install it for couple of days but I couldn't make it. It is so hard to install. I am stuck at cmake part. Is there any easy way to install this plug-in?

Building Houdini Plugin using DLang FFI

Fri, 24 Sep 2021 14:46:13 +0000

Hi everyone!

I was curious if anyone had any experience interacting with the HDK using DLang (or any other language) and FFI?
There is an article about including C++ libraries in D here: https://dlang.org/articles/dll-linux.html and it got me wondering if this was something that could be done with Houdini, and I was curious if anyone else had already tried and what their experience was?

How do I link a .so library that I want to use in my HDK plugin?

Mon, 13 Sep 2021 20:47:06 +0000

Hi everyone!

I recently started working with the HDK and have been trying to set my project up to use an external library, but I don't have a lot of experience with dependency management in C++. It seemed to me like setting something up with a cmake file was the way to go, but I'm having a hard time figuring out the best way to set something up to work with the Houdini environment.

Is this something that is even possible, or am I going about this the wrong way?

Thanks!

Is there any way to get a GA_Offset of a point from an attribute on a point?

Wed, 01 Sep 2021 06:59:50 +0000

Hi everyone!

I have an ID attribute on a point and what i want to do is to use that ID attribute to get it's GA_Offset. Unfortunately I can't find any answers on the official documentation. There are methods of getting an offset based on GA_Index and vice versa, but nothing about how to use an attribute to identify a point offset/index. Unless im missing something...

Appreciate any help!

Noob Syntax question

Fri, 18 Jun 2021 10:55:26 +0000

Hi there,

I am learning C++ and just starting going through the HDK.

I saw this line and I can't understand what (OP_Network *) inside parenthesis is doing, I think I understand pointers and dereferencing enough, but that syntax I never saw before.

Hope you don't mind the simple question.

Thanks.

parent = (OP_Network *)OPgetDirector()->findNode("/obj");

Issue with SpareParms and callback functions

Fri, 21 May 2021 15:09:50 +0000

Greetings!

I have recently started using the hdk to build a custom plug-in (which consist of a SOP Node that modify a heightfield) and I have encountered a deadend (actually more than one, but this forum provided me a lot of help ^^)

In a few words, I am creating a SpareParm by getting the OP_Director (OPgetDirector()) and adding a PRM_Template with method addNodeSpareParm(). My issue is that if I provide a callback function, it is not called back (no result and in debug mode, any breakpoints in the callback function are never reached). I have no issue with parameters normally given when creating the node (I mean when using the newSopOperator() function, a button parameter call back its function correctly).

To fully explain my process: I am creating a node with a path parameter (PRM_File) where I can provide a custom file. This custom file is read and depending on its content, I need to add parameters to the node. From my researches, SpareParms were the only approach suitable. Maybe I am wrong and I will be grateful if you can point me in the direction of a better method.

For instance, this file could give me the parameter ‘width’ with a range and the node would create an integer parameter that would make possible to change the width of the input heightfield.

But the SpareParms that are created do not seem to call the cookMySop() function when modified and adding a callback function that would use the forceRecook() function is not called (as explain above).

Does this issue ring any bell?

Thanks in advance

Luc

Houdini Engine as a javascript library?

Sat, 22 May 2021 16:06:11 +0000

So I had that dream one day...

HDK - Custom File Chooser

Thu, 06 May 2021 16:51:53 +0000

We are moving to URL based filepath's using a custom Asset Resolver in Solaris.

I would like to implement a custom file chooser across the entire Houdini session that could return a URL type from a selection.

I can see you can toggle between OS and Houdini in your prefs.
I can see some File System classes like FS_InfoHelper can work with the value in the parm.

Would I need to to extend the File parm template type? Is this even possible? Is there something in HOM that could do this?

Any thoughts appreciated.

Cheers,

Aaron.

New Operator - Default Colour and Shape

Sat, 24 Apr 2021 18:16:30 +0000

I am trying to set the default colour and shape of a new operator.

I have tried overriding this virtual function in OP_Operator for the color;

virtual UT_Color getDefaultColor() const;

And this in OP_Operator for the shape;

virtual const UT_StringHolder &getDefaultShape() const;

For the return I tried some of the shapes as listed when you print them out using HOM, "bone", "light" etc

https://www.sidefx.com/docs/houdini/hom/hou/NetworkEditor.html#nodeShapes

I am creating a sop driver, so would like to mimic the defaults as seen on these kinds of nodes.

Any ideas on setting these?

Unified high performance framework for OpenCL

Mon, 12 Apr 2021 18:21:07 +0000

Hi everybody!

Check out my video about RnD of framework for robust OpenCL development.

In this video I describe my old developement: framework for development GPU algorithms like cloth/wire/grains/particle/fluid dynamics.
It is implemented as Python code snipped with set of extension functions for control some OpenCL specific tasks.
It gives opportunity to develop complex algorithms without compilation, without HDK/C++, without even closing Houdini sessions.