# All Activity

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3. ## Collaboration with hdbp.io

Well, there's a patreon page: patreon.com/hdbp
4. ## Collaboration with hdbp.io

I talked to Marc from odforce the other day. I am currently developing a plugin for the editor, so people can upload their files via hdbp.io. It will propably take me some time, but it's in the works. Thanks everyone.
5. ## Collaboration with hdbp.io

Fantastic initiative. Deserve more support IMO.

8. ## Intersection stitch with vex

not everything is faster nor easier with VEX, I'd stick with intersection stitch
9. ## How to connect geo to multiple paths

Hi Davor, An easy way to do this is to use the "copytopoints" node to copy the arrows to points on the curve. You can create these with the carve node. You have to create an "N" and "up" attribute to give the arrows the correct rotation. I've made the changes to your hip file. If you have further questions let me know All the best, Luca arrows2Fixed.hiplc
10. ## VEX: Point rotate around curve axis

Oh wow! That works perfectly! Thanks for all the explanations!
11. ## Intersection stitch with vex

Hello and greetings! I have a large amount of curves(branches part of a tree). I then use a polywire to create the thickness of the tree based on some attributes. I am currently using the intersection stitch sop and then a fuse sop to combine my curves into one by fusing the intersecting points. I then put down a resample sop and get a nice even looking geometry. However this process takes about 2 seconds, which isn't too much but I assume I can get this done faster by using vex, but alas I am not very good at vexing. My question is; how would I merge intersecting curves with vex?
12. ## VEX: Point rotate around curve axis

Hi Julien, you need to first transform the point to its local coordinate space before applying the rotation. This is done via (@P-hit_P), then you apply the matrix and finally restore the transform to the world position by adding hit_P again. vector @P; // Get the nearest hit attributes int hit_prim_id = -1; vector hit_prim_uv; xyzdist(1,@P,hit_prim_id,hit_prim_uv); vector hit_P = primuv(1,"P",hit_prim_id,hit_prim_uv); vector hit_N = normalize(primuv(1,"N",hit_prim_id,hit_prim_uv)); // Rotate around the nearest hit point matrix m = ident(); float angle = radians(ch('amount')); rotate(m, angle, hit_N); @P = (@P-hit_P) * m + hit_P; I've gone ahead and updated your file. I've also switched to the xyzdist() instead of nearpoint() function to always get a smoothly interpolated Position and Normal. If you have further questions let me know Cheers, Luca Vex_pointRotateAroundCurveAxisFixed.hiplc
13. ## VEX: Point rotate around curve axis

Hi everyone, With VEX, I try to rotate a point around the closest point of a curve. It seems to work for the rotation but the axis is off! I have no idea how to fix that. here is the file Vex_pointRotateAroundCurveAxis.hiplc
14. ## How to connect geo to multiple paths

I am trying to make arrows to play from source points to target points. I did make paths where the arrows should move Animation works when I have one path. How to connect it to more than one path? Thank you for any help or advice how to solve this arrow.fbx arrows2.hiplc
15. ## Specular Reflection

I'm having some difficulty as I can't get specular reflection on the object. I know PBR rendering unlike in the past which one would use a PBR Specular VOP it is now conjoined with PBR Reflect VOP but I don't see any specular reflection ? This is my material network, hopefully one can see where it is not working.
16. ## Run Maya Standalone from Houdini

in python subprocess.Popen will get you maya open something like this subprocess.Popen(["path_to_maya.exe", r"scenefile.mb"])
17. ## POP_Stream Smooth Transition?

hi, POP_Stream creates other stream by expression. but the rotation is changed in one frame.(at 48f) the attachment file,this is simple scene. the particles go to from Outer Tube goto Inner tube at 48f. ”goto” stream with VOP. How can I make a smooth transition? thanks. POP_Smooth_Transition_v001.001.hipnc
18. ## Run Maya Standalone from Houdini

Probably an odd question but due to how my works pipeline is a lot of assets tend to be broken with the default conversion done for Houdini(usually the camera) and requires a manual export of certain assets from Maya. I'd like to be able to press a button on my shelf in Houdini that will run Maya standalone and run a python script in said Maya.
19. ## Efficient point rendering

I'm rendering a big point cloud from a BGEO file. The only thing that changes is the camera animation. If I use the interactive renderer then the scene updates super quick and renders at about 10-20 secs a frame. If I render using a mantra ROP it takes about a 60-70 seconds. I'm assuming it reloads the geometry every frame (or something!?). Is there a way to get something like the interactive render speeds in Mantra? I've tried using delayed load and disk primitives and also various renderers in Mantra (e.g. micropoly, physical) without much success. There is no lighting or any other vex or vops or anything going on. Simple constant shader. Thanks Simon
20. ## air stream?

How do I make 16 seconds? air stream?

22. ## Locked Hip or Hip Clear Event working really Before Scene Clear

Hi, I would simply ceate a script which creates lock file when a hip is opened for the reason more users should not overwrite their scenes. The lock file should be deleted when a new hip is about to open. So i created a hip event in my scene and check which event is fired (i check the opening hip name). My problem is that I can not fire an event before the new hip is opened ( to clear the lock file ) the event always shows the opened hip not the hip which is being closed. Any idea ? thx!!! G My scripts: ---Registering the event----- hipFileEvent_script = """ def hipFileEventsFired( event_type): import houdini.illessz.events as ev reload( ev) ev.hipFileEvents( event_type) """ hou.setSessionModuleSource( hipFileEvent_script ) hou.hipFile.addEventCallback( hou.session.hipFileEventsFired) ---- The event ---- def hipFileEvents( event_type): # print kwargs if event_type == hou.hipFileEventType.BeforeClear: if not hou.hipFile.isLoadingHipFile() and not hou.hipFile.name()=='untitled.hip': print 'clear event %s' % hou.hipFile.name() else: # print 'clear ?' pass print event_type, hou.hipFile.name() if event_type == hou.hipFileEventType.BeforeLoad: print 'before load event %s' % hou.hipFile.name() # hou.hipFile.removeEventCallback( hou.session.hipFileEventsFired)
23. ## User Defined Channel Name for Mantra Extra Image Plane with Light Export

No one used mantra liked that ?

Thank you.
25. ## Hair collision with accessories

Looking for some production tips for simulating hair on a character with accessories such as glasses. I want to get some nice, accurate collisions with the glasses but first issue I am having is that the animators have keyframed the glasses, so despite initially grooming around the glasses the guides intersect first frame of animated geo. Second problem to solve is that the hair generation interpolates through the glasses and not ‘around’ the glasses (guide collide with vdb doesn’t work too well, especially when trying to avoid collisions with the skin as well) Final thing is not accessory related, but when simming I get this underwater/floaty effect as the constraints try to return to position (all vellum btw). Any tricks to avoid this? Thinking about using plasticity for something more natural but not sure how to manage continuity between shots. Any pro tips would be appreciated!
26. ## I need to move my geometry perpendicular to existing Normals.

Hi, if you made a curve and that your normal is a « natural » normal (not tweaked manually in another wrangle), then when making your curve, output the tangentu attribute. It should be naturally perpendicular to N. Otherwise, create your own perpendicular vector in a Wrangle using a cross product between your N and an up vector defined arbitrarily (in VEX should be something like v@perpN = cross(@N, up); and define up before like vector up = {0,1,0};) Then same code as you have with N: @P += ch(« offsetperp ») * v@perpN;