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art
10-07-2005, 08:50 AM
I have an "object" made out of 1 million polypoints. The points are white and have 100% luminosity. Transparency is set to 0. Render transparency is off in render settings. When I render it, is says "rendering transparent polygons". Any idea why?

Captain Obvious
10-07-2005, 08:58 AM
Turn on raytraced transparency.

Lightwolf
10-07-2005, 09:17 AM
1 point polypoints are basically rendered the same way non-raytraced transparent objects are rendered, so this is normal.

... they can take quite long to render too, don't worry about it.

(Technically, normal polys are rendered in a front-to-back order using the Z-buffer, while transparent objects and single/two point polys are rendered back-to-front to account for the transparency).
In the case of the 1/2 point polys, transparency occurs at the sub-pixel edges...

Cheers,
Mike

art
10-07-2005, 09:17 AM
Hmm, after I turned "raytrace transparent polygons", lightwave went onto optimizing my object which took very long time. I cancelled after a while. I am not sure if it would still proceed to render transparent polygons or not.
My problem is that I do not have any transparent polygons in the object and I do not want to render anything transparent, just bunch of plain white points, but LW keeps on rendering transparency when there seems to be none.

art
10-07-2005, 09:37 AM
Hi Lightwolf,

I guess we posted at the same time. I saw your explanation after I posted my response. Thanks for clarifying this for me. I was just curious why I get the "rendering transparent polygons" message during render. If thats the way LW works, thats good enough for me.

Thanks!

Exper
10-07-2005, 09:41 AM
1 point polygons are always renderd in that way... no matter how you can try.

I know what you're rendering (ehehe) and I can say: "Take patience! It takes long but it renders". ;)

Lightwolf
10-07-2005, 09:44 AM
Hi Lightwolf,

I guess we posted at the same time. I saw your explanation after I posted my response. Thanks for clarifying this for me. I was just curious why I get the "rendering transparent polygons" message during render. If thats the way LW works, thats good enough for me.

Thanks!
Hi art, I saw your immediate post too, that's why I didn't jump in again :)

Yeah, "that's just the way it works" can be quite comforting at times ;)

Cheers,
Mike

Exper
10-07-2005, 10:23 AM
... and art posted while I was writing my reply. Great overlapping Forum mystery. :)

art
10-07-2005, 10:56 AM
I know what you're rendering (ehehe) and I can say: "Take patience! It takes long but it renders". ;)

...and I know that you know :)

It does not look bad, but plain white is boring and gradients offer only limited possibilities.

I have one idea for coloring in mind but it will need to test it more.

art
10-07-2005, 01:39 PM
I tried cheating a little (my first LW workaround :) ) Instead of using polypoins I used point clone plus to replace my points with tiny tetrahedrons.

I had 250,000 points which resulted in 250,000 tetrahedrons (1,000,000 polygons). The render time for 250,000 tetrahedrons was considerably faster than for 1,000,000 polypoints or even 100,000 polypoints for that matter

Each antialiasing pass took apporximately 1 second.

Pros:
speed
nice color shading from antialiasing (all tetrahedrons are single color @ 100% luminosity)

Cons:
4x polygons - my computer refused to deal with 1,000,000 tetrahedrons.
Tetrahedron size must be finetuned depending on render resolution. Tetrahedrons should be subpixel size, but not too small.

EDIT: I should add that triangles or squares could be used instead of tetrahedrons. But then rotating in 3d is not going to work, unless somehow triangles/squares are forced to face the camera all the time.

toby
10-08-2005, 08:48 PM
That's good to know, and a very cool effect! Sounds like you have the right solution, but the object Optimizing can (and usually should) be turned off in the render options panel ('Extra Raytrace Optimization').

Is that 33 pass motion blur at 400% or thereabouts?

art
10-09-2005, 09:01 AM
The image has high antialiasing, but there is no motion blur. The apparent motion trails are inherent part of this type of mathematical objects + lots of points (or tetrahedrons im my case)
This is pretty much the effect you can get by using Aurora's attractor plugin.