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Everything posted by art3mis

  1. Thanks Atom. No, to the best of my knowledge am only changing some ROP settings, but that should have no effect on saved sim information Further searching has led me to believe that "Explicit Caching" is what I need, however I don't see this in H16. Has it been replaced by checkpoints or?
  2. Created a basic 240 frame RBD simulation. Once I was happy with it I wanted to 'bake it' so I clicked "save to Disk' on my Output node inside my AutoDOP network. As a test at frame 120 I interrupted the Save to Disk operation. I also enabled "Playback from Saved files" on the parent AutoDOP node. So now frames 1-120 are highlited in purple on my timeline. At a later time I wanted to see if I could complete the "save to Disk" of my simulation so for start frame on my Output node I entered 121. I then clicked "Save to Disk" but instead of immediately caching my simulation I see "DOP cooking frame 1-120" on my timeline and have to wait an hour or more until my caching operation continues on frame 121. Is there any way of avoiding this cooking operation? It seems unnecessary to me. On a related topic I thought the whole advantage of the .sim format was that it saved state information, so I shouldn't even have to enter a start frame when continuing an interrupted cache operation. Houdini should 'know' where I left off, no?
  3. Ok so I have a visual example so I know what's possible:) As well as a verbal description Three main components to the sim, Pyro, FLIP and a bunch of POP networks. Pyro smoke to advect POP sims for bubbles, getting the inverse of the temperature to drive pscale so bubbles grow. FLIP sim for the leading edge with an age attribute to spawn bubbles when it dies. Sine/Cosine expressions in a copy stamp expression to make larger bubbles spiral upward. All the sims minus smallest foam bubbles are converted to volumes, VDB smoothed and meshed together for rendering. But I'm still stumbling getting anything even close. Anyone know if Andrew is active here on odforce? Would luv to contact him
  4. hmmm, Thanks, no but I did find I can paste my Material SOP after the Boolean SOP using a * ^binsidea group selector. makes more sense as well. And the appearance of the cutgeometry in the starting geometry minimized by reducing the detail in the Convert SOP. Probably not possible to eliminate entirely and using a Switch targeting the frame just before the shatter begins makes the most sense.
  5. Hi I know you need to enable the ‘binsidea’ group on the Boolean SOP for your inside material in a Boolean Shatter fracture. What I’m confused about is proper application of your outside material. In the attached pic you can see I have defined my Outside material BEFORE my Boolean SOP. And my Inside material is after, pointing to the binsidea group. The problem is I am seeing the edges of my cut geometry (vdb spheres) in my Outside material. Am I applying my Outside Material correctly? DO I need to define a group for Outside as well? Should my Outside Material SOP come AFTER my Boolean SOP? BooleanShatter_with RSMaterial_v2.hiplc
  6. Thought this research by Nvidia quite interesting https://blogs.nvidia.com/blog/2017/05/10/ai-for-ray-tracing/
  7. Thanks. Didn't know checkboxes could be dynamically enabled this way...will try.
  8. Hi In my DOP network for a RigidBody test I need to enable "Overwrite Attributes" but ONLY at a specific frame in the simulation. Is this possible?
  9. Thanks I guess I need a better understanding of what is happening 'under the hood' when "Overwrite Attributes" is enabled. How might this be translated into VEX?
  10. Hi When using Voronoi fracture applying materials to the inside surfaces is simple. You just enable the creation of "inside" and Outside" groups on the Voronoi Fracture SOP. But when using a Boolean SOP for a Shatter operation how would you accomplish the same thing?
  11. Don't have time to examine your hip right away but you must be doing something wrong. How are you creating your cut geometry? have you seen the Siggraph session?
  12. Hi Been given a choice at work to either go with a new HP Omen Gaming Desktop with i7 7700K and Nvidia 1080Ti OR wait until the iMac line is refreshed. Any reason to wait for the iMac?
  13. Hi My understanding is that Houdini has supported ptex since v11 and it offers a number of advantages over traditional UV mapping. But will it ever replace it? Outside of Disney, is pTex use growing? What are the disadvantages as compared with UV mapping?
  14. Trying to create a new Vector attribute from normals but keep getting an error "Unable to evaluate expression..." I can't see anything wrong...can anyone help?
  15. in case not everyone has seen already
  16. I know that SESI sometimes makes it possible to reveal deprecated SOPs and DOPS via an 'opunhide' command in the textport like opunhide Sop vopsop Is it possible to reveal the old Foreach SOP this way? I tried the following without luck. opunhide Sop foreach op ok so OLD foreach is NEW foreach Subnetwork I assume.
  17. Thanks! hmmm...very strange. Likely either a change or a BUG in newer Transform SOP?? I've attached a simple .hip that shows the error. I'm running 16.0.687 Linux If I copy paste Transform SOP from 'older' .hip file the error goes away so I assume the SOP logic is contained within the actual saved .hip file, and not the application. newTransformSOP.hiplc
  18. So apparently you cannot use $CEX, $CEY, CEZ anymore? I get a syntax error, invalid syntax! But how would you use centroid() on the Pivot parameters of a Transform SOP inside a For Each block? If I try centroid(opinputpath("."),0) I also get an error, Unable to Evaluate expression. Name 'centroid' is not defined http://www.sidefx.com/docs/houdini/expressions/centroid
  19. Hi Ryan Funny you should mention. Finding out about Boolean shatter for fracturing was what led me down this long road into edge displacement. But in tests I've done so far the results with Boolean Shatter have been EXTREMELY slow to cook, and the results IMHO don't look quite as good as some of these voronoi edge displacement tests! So for now am focusing on voronoi. My vote on the most 'most promising' SOP based approach is Farmfield's. Simple in its execution without tons of VEX code, so something my feeble brain can get a handle on. Still some issues with funky edges and some RBD collision issues when interior detail is enabled on more complex geometry but it's the SOP based solution that seems most promising to me.Hoping others more knowledgeable could take a look at this approach and suggest how it might be improved further. if I had a month free to go over and fully understand each line of VEX in Pavel's amazing SHOP based approach I would probably favor that over any SOP based approach. In my tests as well Pavel's SOP based solution didn't play nice with curved surfaces. note-the attached preview is without inside detail enabled to speed up sim
  20. Hi Encountering some strange Bullet Solver motion in a simulation. Using the RBD Fractured Object shelf tool and a GroundPlane for collision. So the only force should be gravity. But after the fractured pieces hit the ground many of them continue to swim around as if affected by some sort of turbulence. And if I look under the ground plane I can see they actually pass right through creating a sort of debris cloud. Very strange Can anyone suggest what might be happening?
  21. So I've gone thru this thread a few times, downloaded Pavel's excellent examples but was wondering if there is any consensus as to the best SOP based approach to Edge Displacement for fracturing? I am using primarily GPU based renderer's for my work and am unable to translate the Displacement shaders over, one of the reasons I am focusing on SOP based approaches. The problem I am having with ANY of the SOP based examples posted is that they all break when using anything more complex than a simple sphere or cube. Frustrating.
  22. Thanks guys. Setting defaults helped a bit but the main problem was I needed to enable "Create Convex Hull..." on RBDPackedObject node. However there is still some type of collision issue. Almost as if the ground plane was water and the smaller fractured pieces are bobbin in the water.
  23. Op Ok found the answer. so now Surface Model Shader in the new Material workflow is Classic Shader Core but inside a Material Network>Material Builder node https://www.sidefx.com/forum/topic/48599/ Confused though why Surface Model Shader is still in documentation?