Hello,

I want to fracture my object consecutively, say, I have 2 sets of constraints, first break “concrete_fracture_1” then break “concrete_fracture_2”. My purpose is when pieces from first breakage fall onto the ground they break further. RBD Material Fracture node gives these 2 sets of constraint groups but I don't know how to effectively delete them to achieve my purpose. I tried Delete node on constraints only, but it seemed RBD Bullet Solver didn't like animated bounding box.

Hi everyone,

while following the tutorial about Material Based Destruction, the Step 6 is named “Intra-Material Constraints (Studs to Wall)”. I think there is some confusion about using the words “Intra” and “Inter”. Here first sentence says:

“The RBD Material Fracture SOPs have created the inter-material constraints. These are the constraints that define the strength of the bonds between the pre-fractured geometry. For example, how strong and resistant to fracture the drywall is.”

– I think there is a confusion between “Intra” and “Inter”. Here it is about constraining one material to other material which should be “Inter” (Between). And when it talks about the RBD Material Fracture node I think here “Intra” (which means “Inside”) should be used, because the bond is inside the material holding the material's pieces together.

Since this tutorial is technical and the result is dependent on the accuracy of steps, it should be as clear as possible, especially for beginners. Thank you for your attention.


The link to online version is below:
https://www.sidefx.com/docs/houdini/destruction/tutorials/intro_to_mbd_2.html#step-6-intra-material-constraints-i [www.sidefx.com]

Thank you “toadstorm” and “mrCatfish” for the replies.

Hello,

I have many pieces produced by the voronoi fracture. When simmed some tiny pieces are rotating forever and as if they were rounded. I want to fix them so they settle down as the other pieces and also not to roll like a ball. Any ideas friends?

Hi everyone,

I have a scene where I want to set certain objects (packed primitives) be active when an object holding “active” attribute (through Attribute Transfer) moves onto those points. In static mode it works, but if I animate it, it sets all objects active. I know that it is accomplished with the SOP Solver, and I created my moving attribute inside it, but it still does not work. With Group node I can achieve it but I want to do it with “active” attribute by moving it. I have included the scene file.

tamte
you can use Attribute Noise SOP

Thank you Tomas for reply, it is a fantastic node but is specific only to H17, unfortunately I still use H16.

Hi everyone,

I want to give template points noisy movement just like vibrating molecules. How can I use the noise() function to make my template points randomly vibrate?

Thanks Kaloyan and Sadjad Rabiee for replies.

My main reason to bring attribute from MAT into SOP was to utilize Patterns. When I assign one of these patterns (Ramps, Checkered, so on) to my object it works perfectly (both directly onto the object and in Principled Shader), but I want to use these patterns as attributes in my SOP context.

I also tried patterns in VOP context, I guess they require some kind of input. But in MAT context they are rendered perfectly without any input.

Is there any direct and easier way to use these patterns as a part of the attribute on geometry?

Hi,

I want to export an attribute from my MAT context with BindExport and use it in OBJ context, but my attribute comes with 0 value. To bring it into SOP I use Attribute VOP and inside it Bind and BindExport. Is there something I do wrong?

Hi,

when I import AI or EPS files which has text converted into outlines, it gives interior parts filled. If it is one whole object, it is OK, but if the character is made of 2 outlines, the inner outline comes filled.

Exporting from Illustrator as outlines, AI version 8, no compression, no pdf preview, but still no result…

Is there any proven method of bringing AI files with inner outlines intact?

Thank you “vusta” for clarifying it.

Thank you “vusta” for your reply,

yes it helped, I am so grateful.

Can you tell me what does “r” mean in the beginning of the line?

Thx “goldfarb” for your reply,

yes, the way you wrote is a common approach, `$F/2` should slow down the speed. But in this case with the Font SOP, it does not give exactly what it should, because it also gives intermediate values, such as 1.5, 2.5 an so on. How can I get only whole values, i.e. between whole values it could only stick to wholes?

Hi,

In Font node the expression $F is tied to frame numbers, but I want to slow it down, say, by half. How can I achieve this?

Hi,

in Jeff Wagner's Houdini VOPs webinar he shows how to inherit an attribute from SOP to MAT. But I am doing the opposite, from MAT to SOP, and so far no result.

Below is my scene. I use a Ramps pattern in MAT context and export it as an attribute. Then in SOP I import it with an Attribute VOP to use this attribute for PolyExtrude's Distance Scale feature. My attribute value in SOP shows only 0.

So what is the proper way to do that?

I also had a parenthesis in my filename and it threw an error, got rid of it and it works.

Hi,

my second confusion about this presentation. When Scott packages the nodes into the material builder, then adds a Parameter node inside to have a Layer input/output on the packaged material. Then plugs it into the LayerMix node along with Principled Shader, there occurs a problem in the presentation itself. Scott does not fix it and instead opens a pre-made file.

I followed exactly the steps Scott did and faced the same rendering problem. I think if Scott didn't explain the reason of the error, he would be better include at least the file where it works, so we can see the result.

https://vimeo.com/228378251 [vimeo.com]
Time 24:20

Andrea Sbabo
On the principled shader have you enabled under the Displacement tab the option “Enable Input Displacement”? I think he forgot to say it at the beginning

Thank you Andrea for reply. Yes, it could be better if he had said it beforehand. Otherwise I had to experiment to reach to that given point to follow him properly.

Hi,

I am following Scott Keating's presentation (SIGGRAPH 2017 - Lighting and Rendering) where he shows that he uses Principled Shader's “disp” input to create displacement on the grid object. But it does not work as he shows. I want to know where is the problem.

Hi,

say I have a material, named “A” inside a material builder node, which is connected into a LayerMix node, so in combination with the material “B” it creates a new material. I want also to use my material “A” separately in another network. This way I could be more efficient by using the same material in two (or more) networks.

Has anybody idea how can I achieve it?