# mois23

Members

18

• Name
Mattia Maida
• Location
Soverato

## Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

0

1. ## How to round to zero smallest attributes values?

Hi there, just a quick one. I have a cloud of points with an attribute that goes from -1 to 1. Now, if a value it's really small and close to zero (ie 0.00001 or 1e-09), how I can round it to zero? And how I can do it based on decimal? Ie, if value is 0.001 or -0.001 I want to keep it as it is; if value is 0.0001 or -0.0001 I want it to be 0. How I can do it in VEX? Thank you so much!!
2. ## How randomize Retime by an attribute

Hi there, I'm stuck in a really simple problem and I cannot see solution yet. Let's say I have a cloud of points that move with a certain speed (They are not necessarily points that come from a POP solver). Let's say those points have a random attribute that change during time from 1 to 10, then from 10 to 1 and so on... Now, I'd love to use that random attribute as time speed multiplier. If I use a Retime by Speed I'm not able to apply that random multiplier to each point of my cloud, but only to the entire cloud. My goal is to randomize point speed based on that attribute. Is it possible to use that attribute in order to apply a retime by speed for each point? I would love to do that after a POP solver with a SOP Solver or a SOP Retime, but I cannot figure out how to do that. Could you please advise me on a good solution? Thank you so much in advance. PS. I'm not able to upload my current hip file due to company policy. Sorry about that.
3. ## Fire Sparks from Pyro Simulation

Hi there! I'm trying to figure out how to create a POP emitter from Pyro in order to have a realistic (and procedural) Fire Sparks simulation based on heat amount. I've tried something but it's a very rudimentary solution, especially because I'd love to emit particles from top of fire (maybe when heat field falls down). How I can use a pyro field as POP emitter? And, most important, what field do I need to use? Do you have any suggestions, tips or tuts to share with me? Any help will be really appreciate! Thank you for your time. mois_fire_sparkles.hip
4. ## New Pyro Solver (Sparse) and Micro Solvers

Cool! Thank you so much guys!
5. ## New Pyro Solver (Sparse) and Micro Solvers

Hello guys, Just a quick question. I'm studying new Sparse system for Pyro Solver in H18. First change I could see is that Pyro Solver sparse has 4 inputs rather than 5 and “Velocity Update” input is missing. Let's say I want to use a Gas Disturbance micro solver for sparse smoke. How I can connect it to the solver? “Shape” tab in the solver already has a Disturbance option. But, of course, the result is different if I use only the Micro Solver connected to the last input (Forces). So I guess, this approach is wrong. How I can achieve same result using only Micro Solvers? And, first of all.. Does new Sparse Solver allow to use micro solvers? Many thanks!
6. ## Bake geometry displacement as texture

Hi there, I'm having lot of headaches! I made an extended ocean flip simulation and, once I convert the particles into a mesh, I would like to bake the surface geometry displacement as texture. I tried to transfer velocities to Cd through VOP and use COPs for bake out the color map, but I wasn't able to do it. Basically I'd like to achieve the same result of Ocean Evaluate node in which I can export texture and choose the Cusp to be in alpha. Do you think is it possible to do that?
7. ## Whitewater houdini 17

I have same problem If I enable density control. Houdini 17.5 and Windows 10. Did you solve it?
8. ## Custom Velocity with Volume VOP

Hello there, I'm making a classic Ship Sailing Effects (ocean guided). I'd like to add a custom velocity to the bow of the ship in order for me to have a good turbolence like this: Through a Volume VOP (please see the hip attached) I created the following velocity: The shape I had it's what I want (straight velocity to the front and curved ones along the sides of the ship, so they can push the water for having a classic V shape). However, I'd like to invert the value of it: having higher velocity in the center e gradually less on the side. With my solution I have to much velocity on the side and less on the center of the bow. Basically I need the trails to be red (high) at Z=0 and blue (low) at the Max Z bbox. Furthermore, is my solution right? I blast a part of the bow, scattered it and then use a Volume Rasterize Attributes for creating the velocity. And, lastly, what kind of operation do I need to use in DOP in Volume Source? Somebody says "Add", somebody "Pull". What is the correct way? I hope you can help me. Any suggestion will be really appreciated. Ship_Body.obj Ship_Custom_Velocity.hipnc
9. ## Ocean Ship Sails

I tried to fix the shape and keep just the main body, but problem still remains. I did several research (Read Here and Here) and it seems like the main problem is the Reseeding and my geo Velocity Speed. According to Houdini documentation: Setting the various Reseeding values too high can lead to fluid gaining volume over time in very splashy fluid simulations. Decreasing the Particle Radius Scale or the Death Threshold can reduce the volume by causing overcrowded voxels to be pruned earlier. Decreasing the amount and/or bandwidth of Surface Oversampling can help alleviate this problem as well. And also: Reseeding can help avoid collapsing pockets of air forming in the fluid near collisions I'll play around with all reseeding settings and I'll share some results. However, if I disable the Reseeding (as they did in the links above) my ocean shapes collapse. Why this happens? Should Reseeding just populate the shape with more particles? Furthermore, with "Collision detection: Particles" I have good noisy waves but simulation becomes a mess over time. With "Collision detection: Move outside collision" I have a more stable simulation, but too smooth waves and crazy particles flying away. Can't understand the main difference (documentation it's not clear enough). Really? No one can help me??
10. ## Ocean Ship Sails

Hello there! I'm trying to create a ship sailing effect on Houdini 17.5 (with Guided Ocean Layer tool). But I'm having lot of issue. - First of all, as you can see on flipbook, I have lot of particles popping up from ship sides. Why it happens? Can't figure out how avoid this problem. - I used the Deforming Object shelf tool for simulating the ship as volume source. However if I choose Volume as Velocity Type on Flip Solver > Volume Motion > Collisions tab, it looks like fluid doesn't interact well with my geo. Basically I have not splashes, even if I select "Use Volume Velocity for Collision" on Flip Object > Collisions. So I need to switch on Point velocity Type in order for me to have good results. Is that a correct way even if my collision source is a Volume? Is it better to treat collision geometry as volume or mesh? - Is there a way to avoid splashes to slide on surface? I tried to increase the Velocity Blend (on Flip Solver > Particles Motion > Droplets) with no results. - Lastly, I'd like to achieve a good results regarding wave trails (see pictures). Basically I have too rounded and large waves from the ship prow. I'd live to have more V Shaped waves. My scene is more or less in real scale (meters). I used a 0.8 Time Scale value in FLIP Solver in order for me to have good trails, but cannot achieve the desired result. Any help will be really appreciated. Thank you so much for your time. Ship02_Sail_v06.mov Ship_03.hip Ship_Body.obj
11. ## How to delete inside Points with Vex?

Yeah! Works well, thank you!
12. ## How to delete inside Points with Vex?

Hello guys, I'd like to find a way to delete inside points and keep borders (see image) but I can't figure out how to do through VEX. Basically, I need to keep border primitives only in a procedural way. My goal is to create a Grayscale noise on top of an object and convert the white borders into lines (kind of like trace does with COP) . See my hip file. Thank you so much for your help. keepborders.hipnc
13. ## Get name attribute from another node

Hi guys, I'm stuck in a stupid problem. I have a blast node with one point. I'd like to get the name attribute from it and copy in another node (see picture attached). I tried point() expression but it doesn't work. Can't figure out how fix this.
14. ## How create a constraint network for simulating Car Suspensions?

Hey vicvvsh, I tried your solution but with no result (I can't see Spring Constraints in DOP Network). Can't figure out why. (here my car model) Car Destruction v07.hip
15. ## How create a constraint network for simulating Car Suspensions?

Thank you for your help guys. I'll come back home next week and I'll take a look. I'll share my results if it works. Really appreciated.
×