How to add decay to self interfering ripples !

Hey guys,

I've created some self interfering ripples (image1) and am trying to add a DECAY function to the ripples to control the interference pattern and not just have it exist infinitely across the surface. (image2). i.e. I want the ripples to eventually fade out to flat (z=0) and be able to control how quickly/how close to the point that happens!

I found a script tackling this here --> http://www.grasshopper3d.com/forum/topics/how-to-generate-a-sine-co...

although I can't seem to be able to connect it to my script and have it add decay!

image 1

image2

I'm attaching both rhino and GH files please feel free to play around with them and send through!

Here's a close up of the script:

Much appreciated :)

Era

Replies to This Discussion

Permalink Reply by Joseph Oster on January 24, 2017 at 10:12am

I prefer to leave the 'Graph Mapper' domains at their defaults of zero to one, then 'Remap' input and output to/from the '0.0 To 1.0' domains, affected by domain bounds. Then play with the graph to increase the number of ripples and modify their relative magnitudes:

It works with either mesh or brep ('SrfGrid'). 'SrfGrid' takes four times longer to compute 'Contours' but they are much smoother than contours of the mesh.

P.S. I internalized the region and three points so you don't need the Rhino file. It's interesting that your three points are so far ABOVE the surface points. Normally, I would expect them to be at the same Z value as the region you are dividing. It's more fun when you can move them around interactively, even placing them outside the visible region.

Attachments:

170123PodSkin_clean_2017Jan24a.gh, 14 KB

Permalink Reply by Joseph Oster on January 24, 2017 at 10:55am

It's interesting that your three points are so far ABOVE the surface points. Normally, I would expect them to be at the same Z value as the region you are dividing. It's more fun when you can move them around interactively, even placing them outside the visible region.

Like this:

Note: While moving points and modifying 'Graph Mapper', it is highly recommended to disable contours or use the fast contour mesh instead of the slow (but smoother) contour 'SrfGrid'.

Attachments:

170123PodSkin_clean_2017Jan24b.gh, 27 KB

Permalink Reply by Jonathan Kuiper on August 23, 2017 at 10:16am

Hello Joseph, thanks for creating this ripple definition. I am currently brand new to rhino and gh and this is exactly what i needed for a piece of art I am making. My newb question is how do I attach this definition to a solid? I have attached your modified definition so you can see what I am trying to do. I am using your definition to try and make a stone skimming across water.

Attachments:

170123PodSkin_clean_Joseph_Oster_self_intersecting ripples.gh, 26 KB

Permalink Reply by Joseph Oster on August 23, 2017 at 10:22am

There are nine 'Geo' params in your model that are not internalized so the model doesn't work.

Permalink Reply by Jonathan Kuiper on August 23, 2017 at 4:24pm

I fixed that. The reason I was using a separate iteration on each new ripple is so that I could make the "oldest" ripple be a little lower height than the newer one. I think I go the design where it should be but how do I turn it into an actual solid?

Attachments:

170123PodSkin_clean_Joseph_Oster_self_intersecting ripples.gh, 26 KB

Permalink Reply by Joseph Oster on August 23, 2017 at 5:09pm

No, the 'Geo' params are still not internalized (orange components):

Are you not combining the ripples from the three points? In my earlier code, a single surface is the result, which can be extruded (or offset and lofted) into a solid.

Haven't ever tried to model a skipping stone...

Permalink Reply by Joseph Oster on August 23, 2017 at 6:09pm

This is the same code posted in January, point effects combined, with parameter changes: three points in a line, all on the surface, tweaks to graph mapper and scale, etc. Added 'Ext (Extrude)' to thicken rippled surface, in green group. But what is missing is a time element... delays between the three points, such that their ripple patterns are longer on the first skip (point) and shorter on the last.

Attachments:

ripples_2017Aug23a.gh, 25 KB

Permalink Reply by Joseph Oster on August 23, 2017 at 7:58pm

In this version, I added two sliders to reduce the effect of the 2nd and 3rd points to 70% and 35%, which gives the impression of smaller (newer) skips of a rock? Also using 'Loft' for thickness instead of 'Extrude'. Rendering done with Neon.

Attachments:

ripples_2017Aug23b.gh, 28 KB

Permalink Reply by Jonathan Kuiper on August 24, 2017 at 8:01am

Brilliant Joseph!

Thank you so much. I will post what I am making and make sure you get the credit for this (if it looks the way I am hoping. If it looks like crap then I won't drag your name through it lol). If I want to add this .gh to a solid do I create the solid before opening up the definition or after? Sorry, I am as green as they come in GH & Rhino.

Permalink Reply by Joseph Oster on August 24, 2017 at 8:05am

The rippled surface IS a "solid" (a "Closed Brep").

Permalink Reply by Jonathan Kuiper on August 24, 2017 at 3:31pm

Hmm perhaps I mean a surface. I want to export it to mill so a .stp .obj

Permalink Reply by Joseph Oster on August 24, 2017 at 6:18pm

What you see rendered above is a "Closed Brep" that has been "baked" from the GH model to Rhino. The top surface is rippled, the other five surfaces are flat. Since they are joined and fit as a "Closed Brep", they will be treated as a solid.

Thickness is determined by "wave height". This version adds a "Base Thickness" slider to add more thickness on the bottom, by moving the XY plane we 'Project' onto down.

P.S. What are your final dimensions for the milled piece?

Attachments: