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Everything posted by blackchicken

  1. Python export selected nodes, netbox

    thanks a lot @bunker but we have scenes with tons of assets and we would like to find quickest solution, for loading, rebuilding different scenes. Exporting more simple scenes at once from one main scene. For now hou.hipFile.merge() with node_pattern* works somehow.
  2. Python export selected nodes, netbox

    Hello guys, is there some clean way, how to export selected nodes, netboxes to clean hip scene file? We cant find any simple solution. Now we exporting json with list of objects, merge scene to new clean scene and delete all except list. Crazy, but it works. Thanks a lot for ideas.
  3. Bullet deforming static geometry substeps

    Ok we found it. If you use timeblend , interpolate quaternions and transform must be on for packet object.
  4. Bullet deforming static geometry substeps

    Hello guys. I found strange behavior in bullet. I have medieval wooden cart, full of heavy stones, moving fast from the hill. By default, bullet have 10 substeps, should be good enought. Cart is rigged, and it is deformed, twisted so I need him as deforming static object. If I check cart with timeblend, frame increment 0.1 in SOPs, I can see slight movement of geo, dive to DOPs, bullet stones fall, but my cart, deformed static geo is jumping on full frames. No movement inbetween frames. That causes ofcourse incorect collisions and all kind of bad things. I tested in H18, H18.5 same results. So I never had collision geometry substeps??? Is there some easy fix, how to force bullet recompute deforming static object every given substep? Thanks a lot.
  5. Substeps cache problem

    Hello, I need to save caches and use it as Slow Motion 10x . I use increment in rop - file cache, but it seems it does not work. Substeps 2, 4 are ok but 5 and 10 not, viz pict. Its some bug? I can use $N, its asset sim on zero pos and use timeshift for now but I would prefer proper substeps saves. Thanks a lot.
  6. Krakatoa in vex

    Hello, I`m working on Ink style effect. I would like to add point in between two (or more) nearest existing points, interpolate velocity and push new point slightly in vel direction, to have little bit more circular interpolation. That works well, better than point jitter or different cheap techniques. I would like to still fell motion from original sim. But I stuck on duplicated positions of some points, which is logical, other points can have similar near point. So I would like to add some counter, so if there were pair in past, don`t create new point. We are talking about millions of new points, so I need it as cheap and straight forward as possible. Basic idea, with some new points duplicated: float maxDistance = chf("maxDistance"); float minDistance = chf("minDistance"); int maxPoints = chi("maxPoints"); int nearPnts[] = nearpoints(0,@P,maxDistance, maxPoints); foreach (int pnts; nearPnts){ float distance = distance(point(0,"P",pnts), @P); if (distance > minDistance){ vector nearPos = point(0,"P", pnts); vector nearVel = point(0,"v", pnts); vector centerPos = lerp(nearPos, @P, 0.5); vector centerVel = lerp(nearVel, @v, 0.5); centerPos += centerVel * chf("pos_offset"); int newPoint = addpoint(0,centerPos); setpointattrib(0,"v",newPoint,centerVel); setpointattrib(0,"id",newPoint,@id*1000); setpointattrib(0,"newBorn",newPoint,1); } } I`m trying to add some counter ("tested") but seems like I cant read this attribute and my head is twisted I can see in spreadsheed, that "tested" has some range, so I need to connect with it. Any idea? Thanks a lot float minDistance = chf("minDistance"); int maxPoints = chi("maxPoints"); i@tested = 0; int nearPnts[] = nearpoints(0,@P,maxDistance, maxPoints); foreach (int pnts; nearPnts){ float distance = distance(point(0,"P",pnts), @P); setpointattrib(0,"tested",pnts,1,"add"); if (distance > minDistance && point(geoself(), "tested", pnts) == 1){ vector nearPos = point(0,"P", pnts); vector nearVel = point(0,"v", pnts); vector centerPos = lerp(nearPos, @P, 0.5); vector centerVel = lerp(nearVel, @v, 0.5); centerPos += centerVel * chf("pos_offset"); int newPoint = addpoint(0,centerPos); setpointattrib(0,"v",newPoint,centerVel); setpointattrib(0,"id",newPoint,@id*1000); setpointattrib(0,"newBorn",newPoint,1); } }
  7. Hello, I have little problem with chops. When I modify bones inside OTL with chop network which is inside OTL too, my export chop put absolute path of my bones and OTL ofcourse dont like it. I search what to do but cant find anything. I tryed change export prefix but no change. Any idea? Thanks a lot.
  8. Curve selection with near point

    Thanks a lot Tomas, that`s exactly what I`m looking for. I was lost in different loops but I knew there`s some really simple solution, like that one.
  9. Hello I`m searching for most effective way how to select (pair together) only one nearest curve of specific scattered point. I have T-pose baked curves (Fur curves, million of points) and I need to simulate them. I`m separating longest lines, where sim will be visible, then I`m scattering points on given surface (skin) with scatter relax, so I have nice, even distribution of points. Now, I cant find nice way, how to separate only one curve with nearest distance to specific scattered point. In the end Ill have same number of curves as my scattered points. Little scene attached. Also second step will be most efficient way how to transfer simulated guides back to baked Hi-res furs. Point deform is quick way but I`m looking for something super efficient. Don`t need extra details with transferring per guide, I`m looking for speed. Point cloud with radius with blending position is best bet? What do you think? Thanks a lot for ideas. curve_selection_v01.hipnc
  10. Hello, I think I saw it somewhere, but cant remember, and cant find some info about it. I have a ton of cameras as gizmo for UV projection for Vray materials. I would like to hide them in camera menu and want to see only cam_render. Is there some way? Otherwise, it will be total mess if I have like 80 custom projections. Thanks for tips.
  11. Camera menu, hide cameras

    That`s perfect, I knew it is possible. Your mine guardian angel for many years So when you`ll come back to Prague?
  12. Python setHSV

    Hello I`m stuck with setting correct color to nodes. I would like to set value with HSV. I want to do slight automatic gradient when I creating nodes in network box this one work in RGB: my_list = [nullA, nullB, nullC, nullD] loop = 0 nodePos = -1 for node in my_list: node.setColor(hou.Color(0.3, 0.5 * loop, 0.8)) node.setPosition(hou.Vector2(0, loop * nodePos)) loop += 1 but cant find the way how to set values with HSV, from doc should be something like this: my_list = [nullA, nullB, nullC, nullD] loop = 0 nodePos = -1 for node in my_list: node.setColor(hou.Color().setHSV(50, 0.5 * loop, 0.8)) node.setPosition(hou.Vector2(0, loop * nodePos)) loop += 1 Thanks for help, Jan
  13. Python setHSV

    Thanks a lot Symek, still soo much to learn
  14. WIP - ok++'s softbodies RnD + .hip files

    I just want to say thanks for sharing, there`s a ton of very useful information, simple, yet very powerful techniques. Exactly what ours supervisors wants from us every day
  15. Bullet penetration

    Hello I have scattered points, a lot of them and I copy some simple objects, which represents roughly my Hires Geo. Problem is, that whole system is procedural, so I never know if Ill be simulating 20k or 50k objects. Ofcourse more objects, more penetration on first frame. So I have an idea, to do a small sim, where on couple of frames play new bullet sim and all penetrating objects will move until theres no penetration (say time shift 10-20f). Then I`ll start my main sim without penetration (a lot of different constraints, some groups of active objects.....) But problem is, that bullet do nothing even there`s a lot of penetration. I cant find any parameter in bullet solver, rbd packet prim, which will help me. Ofcourse Ill be happy to hold main shape as close to original as possible. There is simple scene. Thanks a lot. bullet_penetration.hip
  16. Sails and ropes

    Hello I have some scenes with lot of sails and ropes. I`m solving two problems: 1, Cloth speed in Houdini.... you know,but I have problem move cloth realistically. There`s tab Drag in Cloth Object, but it does not work. I can set External Velocity Offset which I want, but there`s no change in sim. As I understand, it`s basic cloth regular wind force. With 3+ DOP fans I don`t have good results. Drag tab should be something like maya Ncloth default wind right? 2, Ropes. Which technique I should use? I need ropes to collide with clothes, two ways. One way is simulate ropes alone and then collide with cloth, so ropes deform clothes. Other way is simulate all together. I`m very new in grains, is this a possible way? I still thing specific parameters for cloth is better but problems with wire colliding, tiny sheets of cloth does not work too. What do you thing? I will be happy stay in houdini and don`t want to simulate all in maya ncloth. Thanks a lot.
  17. Sails and ropes

    Thanks for answer. Main thing which makes me sad is that Drag does not work, i need nice subtle realistic motion of cloth. I have no problem with FEM cloth and speed I can handle this, but movement is problem now.
  18. Hello, I have a problem with delayed load. In previous versions, I have no problem with mantra rendering, if delayed load has missing frames (negative frames -> not simulated). But now, I have error and mantra don`t render. It is possible in mantra, turn off Missing frames report like in file SOP? There is option for Report Error or No Geometry. I cant find something like this in delayed load or in mantra settings. Thanks a lot.
  19. Cheap underwater bubbles from HOT

    Hello, some guys asks me on vimeo about this setup so here is little hip. Its different scene (I lost original ) but same setup. Hope someone helps. blackchicken_foam.hip
  20. Hello I have a problem with water level. I have really simple fluid conntainer, whitewater from shelf and simple collision object which is not inside fluid container at first frame. When I have low res sim, all is ok, water level is zero. But When I add resolution, after say 100 frames, my water level is bellow zero. A lot. Thats is problem because I collide with boat and need water level to be zero. I set particle radius scale to 1. Thats what do the problem? I need really Hi res sim around 100mil particles. Any idea helps Another problem which I found is that in some frame random particles onside all fluid container has some velocity, frame to frame. In places where nothing happening. It makes later problem with vel transfer. No big deal bud I dont like it. If anybody has same problem,let mi know. Thanks a lot.
  21. Hello I have problem with exporting multiple objects (nodes) from houdini. If I want say only two nodes I select it in FBX Export Options/ Source Objects/ Export say: /obj/Glass_Anime_A /obj/Glass_Anime_B but houdini writes Could not find the start node specified [/obj/Glass_Anime_A /obj/Glass_Anime_B] I just must delete all object from scene except objects I need to export then leave /obj and all export fine. How I can write right path for correct export FBX? Thanks a lot.
  22. Export multiple nodes as FBX

    Grrr thats no good news Of course I collapse objct which I want export and then in fbx exporting only one node. Thats ok. But sometimes I have complicated scene, I have objects parented to another things, some fetch from differen node trees. Sometimes I cant collapse them. And what if I need export 50 different objects? Ben Ill try Bungles. Thanks a lot.
  23. Geometry from points

    Hello, I have a question. I have very dense ground mesh, and I need it to reduce, just for better work in viewport . I need ground only for collision and don`t need so much details. I could use polyreduce but it is so slow. It is possible use scatter (I can paint interesting area for more points = more details) and then connect nearest points into polygons? Triangles is ok. Is there some tool? Don`t remember I need something like this in past. Thanks a lot.
  24. Geometry from points

    Thanks a lot guys, remesh work perfect.
  25. Pin RBD to Wires

    Hello, I have a question how to pin RBD object to wire. Lets say something like heli and some load on rope or weapon with chains and sphere with spines. It is possible? Thanks for ideas.