Paint Cracking Method

[PixelNinja 42]

Hey all.

I tend to read these sorts of forums a lot but never actually contribute anything, so I figured I should change that.

Here's a somewhat lengthy write up of an approach to peeling paint off of a wall:

http://www.pixelninja.design/paint-flakes-in-houdini/

I haven't been using Houdini long (only a couple of months) so there's probably much better ways of doing this. If so, let me know!

Hopefully it's easy enough to follow along with. Blog/tutorial writing isn't something I generally do, so if you've got any feedback I'd love to hear it.

Edit: added a hip file as per a request

paintFlakes.hipnc

Edited February 9, 2017 by PixelNinja

[mestela 566]

Super cool.

 

[PixelNinja 42]

Thanks Matt

[Diego A Grimaldi 78]

Only couple of months? Wow man, nice stuff!

[cudarsjanis 39]

Thank you, this is what I was looking for.

I enjoy tutorials like this way more than video ones.

Thanx!!

[PixelNinja 42]

7 hours ago, Diego A Grimaldi said:

Only couple of months? Wow man, nice stuff!

Thanks Diego 

I'm finding that a lot of Unity concepts (and game engine stuff in general) is pretty transferable to Houdini, which helps a lot.

[PixelNinja 42]

7 hours ago, cudarsjanis said:

Thank you, this is what I was looking for.

I enjoy tutorials like this way more than video ones.

Thanx!!

Thanks, I'm glad you liked it.

I tend to agree, the pace of videos sometimes is quite slow, and it can be difficult to jump around and refer back to things.

[adrianr 41]

20 hours ago, cudarsjanis said:

Thank you, this is what I was looking for.

I enjoy tutorials like this way more than video ones.

Thanx!!

 

Completely agree. That's why I love Matt Estelas cgwiki so much. Loads of valuable info that's really fast to reference, plus everyone loves a good gif. 

Great tutorial Pixel   

[Atom 792]

After spending a couple hours on trying to interpret this tutorial I still can not complete it. Parts of it do not make sense to me. If I disable init_borders then the group no longer exists and solver has nothing to operate/transfer upon.

Can someone take a look at my work-in-progress and tell me where I went wrong in trying to re-create this scene?

ap_paint_flakes_tut.hiplc

Edited August 23, 2016 by Atom

[PixelNinja 42]

8 hours ago, Atom said:

After spending a couple hours on trying to interpret this tutorial I still can not complete it. Parts of it do not make sense to me. If I disable init_borders then the group no longer exists and solver has nothing to operate/transfer upon.

Can someone take a look at my work-in-progress and tell me where I went wrong in trying to re-create this scene?

ap_paint_flakes_tut.hiplc

Looks like there were just a couple of little issues.

The main one: In the solver accidentally connected input1 into the attribute transfer (the sphere is coming in from input2).

Also, try setting your grid rows and columns to 2, that way the voronoi pieces are blank ngons, and the remesh can do its thing without distorting the mesh.

Lastly (slightly less important), set the border group to points. It does work as a primitive group, but then the cracks can't be as fine.

 

Let me know how you go  

 

With regards to @active not existing when you disable initBorders; when the attribute transfer does it's thing it will automatically create it on the mesh (if it doesn't exist) and initialise its value to the default (0).

ap_paint_flakes_tut_edit.hiplc

 

Oh, one other thing. If you keep having issues after that (mesh not displaying correctly, colour node not working), make a new scene view. I had to do that a couple of times with your file for some reason. Some things just seem to lock it up.

Edited August 23, 2016 by PixelNinja

[PixelNinja 42]

9 hours ago, adrianr said:

 

Completely agree. That's why I love Matt Estelas cgwiki so much. Loads of valuable info that's really fast to reference, plus everyone loves a good gif. 

Great tutorial Pixel   

Thanks

 

Yeah I'm sure you can tell that was the influence here. All of the gifs!

[dichbg 0]

Hello.

This is a great tutorial, I am just starting with Houdini.

I am working on houdini 16, and the simulation is extremely slow (i waited 30 minutes for the first collision frame, and stopped the simulation).

Is it supposed to be this way?

Thank you in advance.

EDIT:

I found a solution.

1. Instead of Finite Element Solver, use Cloth Solver. (Optional)
2. In the collision tab of the cloth object, uncheck "Collide within object".

Edited April 25 by dichbg
Found Solution.

[PixelNinja 42]

Hi,

I'm glad you found something that worked.

Yeah I can't remember if I was using self collisions or not. In general though I have found the cloth solver in houdini to be incredibly slow.

I still find myself jumping to ncloth in Maya most of the time. There's so much less control but at least I can get a decent sim out quickly.