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Fractal Art => Movies Showcase (Rate My Movie) => Topic started by: Alon Nahary on August 28, 2016, 10:15:34 AM




Title: Objects Collection
Post by: Alon Nahary on August 28, 2016, 10:15:34 AM
https://www.youtube.com/watch?v=xwD3Ju-CVSo&feature=youtu.be

About the rendering:

I wrote my own software I call Julia3D.

Fractal function only returns true of false it a 3D point is part of the set, so I sample points around in order to get the normal for each point.
The objects created by scanning the 3D volume by ray marching method, to create a point cloud with normals.
The point cloud is then sent to Poisson triangulation.
Depends on the surface area, the simple objects are about 5 million polygons, the most complex object is 106 million polygons (Algorithm 7 Object 3).

After the triangulation, each vertex is getting an ambient value with ambient occlusion, again with ray marching.
Preparing the object is done in C++ parallel processing, and it takes about an hour per object on my 12 cores machine.
The rendering is done in DirectX shaders. The coloring is done by the distance from 0,0,0 point, and I added to this version directional light, shadow mapping and specular.

There is also a grayscale version with ambient light only in:
https://www.youtube.com/watch?v=jfRdYN_Os6Y&feature=youtu.be


Title: Re: Objects Collection
Post by: Alon Nahary on August 28, 2016, 01:06:15 PM
Removed duplicated links.


Title: Re: Objects Collection
Post by: lycium on August 29, 2016, 04:08:51 AM
Hope you don't mind my asking: why use point clouds / polygons to render objects which have distance estimators?

It's very easy to ray trace these objects directly, and get much higher surface quality, without using any memory at all pretty much.


Title: Re: Objects Collection
Post by: slon_ru on August 29, 2016, 07:34:11 AM
Cool!
Looking forward to try out your software  :beer: :beer: :beer:.
br
 


Title: Re: Objects Collection
Post by: 3dickulus on August 29, 2016, 08:10:52 AM
nice work  :beer:
did you use Point Cloud Library (http://pointclouds.org/) or CGAL (http://www.cgal.org/) ?
or have you coded the pointcloud and geometry stuff yourself ?
do you plan on releasing your program ? and/or source code ?


Title: Re: Objects Collection
Post by: Alon Nahary on August 29, 2016, 09:00:28 AM
Hi 3dickulus  :)

I use my own code for the point cloud processing, my day job is processing Lidar point cloud among other things, so I don't need much. The triangulation is external, I use PoissonRecon.exe in command line:
http://www.cs.jhu.edu/~misha/Code/PoissonRecon/Version8.0/

All of the rest is mine, ambient occlusion, render and animation.

No plans to release it for now, I have some hopes to sell 3D printed objects of the shapes one day as an art form...


Title: Re: Objects Collection
Post by: Alon Nahary on August 29, 2016, 09:22:18 AM
Hi lycium,

There are several reasons why I use 3D polygonal object instead of ray tracing them:

1. I don't have distance estimators to any of the algorithms. Most of the algorithms I discovered by accident by looking around, manipulating and manipulating until I get something. That makes my ray tracing rather slow.
2. I have a ray tracing code, this is how I test the algorithm and find the objects. The thing is that some of the objects have aliasing on the surfaces and on edges, animating that will be very noisy. When you triangulate an object you get a stable object that you can rotate around. Of course it should be very detailed.
3. I have a 3D object anyway. I developed it for my dream of 3D print it the shapes. 3D printing uses a slicer algorithm that needs an input of a polygonal objects. I haven't tried to 3D print any of the objects yet.
4. The videos are 16000 frames each, that's a lot of ray tracing, so I thought, if I already have the 3D objects, I'll render it with DirectX shaders and pull the images out of the graphics card. It took me two and a half hours to render each movie, one with grayscale and ambient light shader, and one with colors, directional light, shadow and specular shader.

I'll post some images from my ray tracing soon.


Title: Re: Objects Collection
Post by: Alon Nahary on August 29, 2016, 09:33:41 AM
From my ray tracer, with some aliasing:


Title: Re: Objects Collection
Post by: Alon Nahary on August 29, 2016, 11:17:10 AM
And another ray traced one:


Title: Re: Objects Collection
Post by: 3dickulus on August 29, 2016, 02:16:43 PM
very nice  :toast: