Hello there,

I am still pretty new to Houdini, but its getting more and more frustrating as I try to get more into detail with stuff that i've been doing very intuitive for while inside 3dsmax/thinking particles. I know, it is a totally different level and a much more complex concept, but it feels like the learning cuve and furstation tolerance are almost at water level.
Every day I run into small stupid problems/questions which are just exhausting to figure out.

For example, why are there VEX functions like “arraylength” which are only available inside a VOP but not in a pointwrangle. And vice versa for the function “nearpoints”. A lot of the stuff is very poorly documented, especially vop nodes and it takes a lot of time to find the right one as well as the right way to use it. When I recently asked a software developer to help me, to get a pointvop running, he looked into it, looked into the documentation, got angry and said: “sorry but this sucks”. And in addition to that, a lot of tutorials have become kind of outdated since a lot has changed in the software during the last years.

Not sure, is it just me or are more people out there having similar difficulties getting into the software?
How do you guys do it?

Is there a kind of debugging tool to check out whats going on inside a network? (I recently tried to write a random number into an attribute a pointvop using “random”, but I ended up with just the same random number for each point without beeing able to find out why..)

Are there any tutorials/trainings you can recommend, especially for basic stuff like vops and fundamental stuff?
Sure there are a lot of great workshops and tutorials out there, but a lot of them are just scratching the surface of different topics without going into detail. And in my opinion, there is no point in setting up fancy fluid simulations or pyro renderings without an in depth understanding of whats going on. Without that, there is now way to really push the boundaries which we usually run into with other software packages.

Cheers
Felix

Hi Felix,
yes it is a lot to learn.
It took me quite a while to get the drift. I now know enough to be comfortable in Houdini.
But this is not full time learning and experimenting. Maybe something like 500 hours before i had the aha moment of - “I dont want to use any other 3d software anymore” (I used max for ages!)

I think the paid tutorials at pluralsight are great to start with. I also really like http://www.rohandalvi.net/ [rohandalvi.net] i actually think this is the best out there. BUT: there is a lot of tutorials that are great basically for everything there is great tutorials. Problem is a bit that it all comes together at some point and before that you feel lost.

About the docu: look at ALL the sample files at least once! There is a lot to learn.

some of my personal favs:

- http://www.rohandalvi.net/textures/ [rohandalvi.net]
- http://www.rohandalvi.net/shader/ [rohandalvi.net]

https://vimeo.com/41727309 [vimeo.com]

https://vimeo.com/67677051 [vimeo.com]

also have a look here
http://houdinitricks.com/category/quicktips/ [houdinitricks.com]
http://forums.odforce.net/ [forums.odforce.net]

there is a paid very new course on wrangle: https://www.sidefx.com/tutorials/creating-custom-solvers-with-vex-wrangles/ [sidefx.com]


greetings

Olaf

@arraylength:
the function you want is len(). If you look inside the arraylength node you see that it's just a snippet with the function len() inside.
Point wrangles in general are nothing more than snippets inside an attribute vop ( again look inside the node and see what's going on under the hood ).
So if you feel something is missing you can just lay down a snippet node and use that inside vops ( or create your own vop hda with a snippet inside like arraylength )
VOP Networks generate vex code. If you right click on a pointvop and select > VEX/VOP Options > View VEX Code you can see what code it's generating.

@“debugging”:
You can see all the point / prim / vertex values in the geometry spreadsheet. In earlier versions of Houdini it was called detail view.
( You seem to have asked the exact same question 2 years ago and you got an answer btw )

@tutorials being outdated:
This happens when a company is not afraid to reinvent and overhaul it's software.
Unlike the mighty Kraken that is Autodesk, which just buys plugins, renames them and calls that “innovation”. I can't count how many times I heard the phrase “maybe it's fixed in the next release”, while SESI sometimes fixes your bug within a few days (!) and puts it in the next daily build.

Instead of having some random guy try to help you out with a software he doesn't know, maybe you should have just asked in the forum ?

Every software has it's pros and cons. In Houdini the learning curve is steeper, but you get a huge toolset with a flexibility that is unmatched in other packages.
If you need a tool for a specific task you can almost always create it yourself and pack it in an HDA.

For VEX/VOPs, I would recommend trying to stick to VOPs at the beginning if you are just starting (and you are trying to do “simple” operations). Although you sometimes feel like you can just “code” something really quick, the beauty of Houdini is that you do not have to. This will allow you to learn “vocabulary” without having to worry about “syntax”

After you get comfortable with the vocabulary, then I feel learning the syntax for vex code is much easier, as you will know what you want to do, and are just trying to figure out how to do it in VEX instead of VOPs. At that point, like BlackPixel said, you can always make a quick vopnet, right click on it, view vex code, and find the syntax to the function you were looking for. VEX is actually a lot like shading languages (HLSL, GLSL), so when I use a snippet, I tend to get into “shader writing” mode (although some of the new array stuff borrows from python, and some of the sprint manipulation stuff is very C based). You can also click on the small drop down menu on the right of your code box to see some quick examples

I started Houdini before snippets even existed, and learned a lot of my vex by using VOP networks… and I am glad I did I feel for me once I got comfortable with VOPs, that was the moment at which I simply could not go back to other software (doing stuff in Maya right now feels like I am moving in slowmo…)