Has this been resolved yet?

I was just looking for a way to do this as well. Would love for there to be a way to translate a SOP attribute to pruning in LOPs when using SOP Modify or SOP Import.

Using the output of the Visibility SOP for example would be nice.

And using similar logic, translating the Alembic Visibility to Pruning when importing Alembic Geometry to LOP and layering it on input geometry.

I have the same issue running Windows 10 on my MSI GS73 laptop on 16.5.571. Any version 16 or above crashes. 15.5 works fine.

It might not be exactly what you're looking for but if you click on the little gear in the top right corner of the camera parameters and select “Edit rendering parameters”. You should then be able to add the “Lens curvature” to your camera. It's fairly simple but might get you somewhere along the way.

The points() expression is for strings.

To get Cd, which is a vector you should use point() instead.
Make sure to specify which component you're after as well.

You could use the Measure SOP to give each primitive an area attribute, and to sum it all up you can use a Attribute Promote SOP promoting with Sum as Promotion Method.

As usual there might be other ways as well but that's the first I come to think about.

An other tip might be to write out the geometries to bgeos after import.
I don't really trust FBX files so I have script which writes out all the selected nodes from an FBX and writes out a bgeo-file read in from a File SOP instead.

kaschalk
I'm trying to use this method to give the object translation value in pixels. Assuming the vector blur data is in ndc space, I would think multiplying against the resolution would give you the desired result, but I don't find a correlation.

For example, I have an object moving 136 pixels in Y. The image is 1K square. The value returning is 0.511 (x1000 = 511)

Any ideas of what's missing, or is my logic completely off?

Thanks!

I haven't used the shader in quite a while and just noticed that it doesn't seem to work in H11. There seems to be no “tondc-node” anymore.

I suppose it's possible to write the shader in VEX from scratch but that's unfortunately nothing I've got time to do right now since I've never written any VEX-shader without VOP and have my hands full with production stuff.

That sure looks interesting. I'll give it a try!

I'm trying to get a nice result of backlit/translucent hair/fur using Houdinis built-in fur system/shader. However I'm running into a problem as the hairs are casting 100% opaque shadows resulting in that the light dies of way to early in my fur.

What is the best way of achieving this look? I'm after a quite prominent effect.

http://www.flickr.com/photos/singingpixel_photography/124613590/ [flickr.com]
http://www.flickr.com/photos/angelakleis/2215946284/ [flickr.com]

I noticed that after installing Houdini 11 some of the lighting/rendering parameters and workflow has changed, and that the default settings for the environment light for example, still produces fast results, however they basically look like TV noise now.

So I've played around a little with the settings and tried to make a (as far as I know) fair, simple scene to compare performance and try settings in.

I have probably/hopefully missed something somewhere, but I have a hard time reproducing the same image quality in Houdini 11 without it impacting the render times quite a bit.

A simple scene with a sphere on a plane and a environment light produced the following results after I've matched the noise by adjusting the light and reflection samples, leaving all other settings the same in both scenes:

H10, Clay only: 2sec
H11, Clay only: 5sec
H10, Reflection/Checker: 4sec
H11, Reflection/Checker: 10sec

Sure these are short renders thus a bit unpredictable but so far in my experience Houdini 11 takes quite a bit longer to produce similar results, especially with smooth shadows and reflections.

Also the texture filtering is very different looking at the checker in the back, in Houdini 11 it seems to just remove all contrast whereas in Houdini 10 the checker stays crisp.

edward
Your syntax is wrong. Backquotes (`) are only used to get INTO the expression language (eg. from string parameters). It has no meaning if you're already in the expression language (eg. when the parameter is green).

Therefore, the corrected (untested) syntax should be more like
ch(“../null1/size” + chs(“../null1/index”))

Works perfectly. Thanks!

Let say that I have a control node with the following attributes:

int index
float size1
float size2
float size3
float size4
etc..

Now if I would want to let the index parameter control which of the size attributes to read from. How can I do that?
I tried the following which didn't work.

ch(“../null1/size`ch(”../null1/index“)`”)

However, if i write the following it does work:

ch(“../null1/size`$F`”)

The problem is that I'm trying to reach an attribute outside my Foreach SOP corresponding to the FORVALUE which as I access through stamping.

Could I perhaps somehow create a global variable just like $F and change it to the stamped value for each loop?

Depending on how the points are positioned you perhaps could try using the Particle Fluid Surface SOP. But that might not give you the desired result.

Works like a charm! Tackar!

I have a Python script running through a Script SOP and I need to access the node connected to the Script SOP in my python script. This is no problem at the moment since I can just hard code the location of the node. However it would be way better to have the script itself know which Script SOP it's running from, and then use the input of the script node.

So, how do I get my script to be aware of which node is running it?

I need to extract the XYZ rotation that the Copy SOP applies to an instanced object on each point.

What I'm trying to do is export all the attributes of my template points to a text file, including the rotations which are applied to the objects which are instanced upon the points.

I suppose that doing some matrix/quaternion -> vector conversion is what I'm looking for, but my limited programming/mathematical skill is taking it's toll I guess.

I know there are a couple of threads both here and on odForce regarding this matter but I've gone through most of them without any luck.

I've attached a hip-file to illustrate. What I would want is to extract the rotation of the teapot which the Copy SOP applies to it. And rotate it without having to use a Copy SOP at all.

Thanks!

mzigaib
Hi, I am doing some crowd too, I I'like to ask for a little help, can you tell me how did you use CHOPS with instancing to offset the speed and animation?

Thanks

Hi, well I was using geometry caches which are read in CHOP's. Those in turn were connected to Shift and Stretch CHOP's if I remember correctly. These were using copy stamping to get the offset different on the Shift CHOP.

On the Stretch CHOP which controls the speed of the animation I used the speed of the particle divided by the size of the individual so that a small hen would move faster than a big one running at the same speed.

Hope it makes some sense to you.

Updating to 10.0.554 solved the problem.

Thank you! That pretty much confirms my theory that it is something weird with our installation.

We're running 10.0.249.5 on Linux at the moment but we're going to update to the latest version now hoping it will resolve the issue.

I'm trying to export a RIB with motion blur. However I can't get the MotionBegin block to be set to 0 1, even though I force it in my export.

I've attached a sample scene for you guys to try with.
On my system it produces a RIB with MotionBegin .

Is there any parameter somewhere which I should change perhaps?

Thanks in advance.