Sat, Sep 21, 10:38 AM CDT

Renderosity Forums / Poser - OFFICIAL



Welcome to the Poser - OFFICIAL Forum

Forum Coordinators: RedPhantom

Poser - OFFICIAL F.A.Q (Last Updated: 2024 Sep 21 10:01 am)



Subject: Global Illumination Logic


  • 1
  • 2
cainbrogan ( ) posted Sun, 22 December 2002 at 8:35 AM · edited Sat, 21 September 2024 at 10:36 AM

Attached Link: http://www.renderosity.com/messages.ez?ForumID=107&Form.ShowMessage=775196&Form.sess_id=2047682&For

file_37495.jpg

First a little background. The attached link is of the best model of Global Illumination I've seen to date. Secondly lets recap how Poser 5's Light Setup is, and see if we ca'nt visualize, at least for a moment, how the Bryce model could be replicated in Poser 5. The 1 light is positioned at 0,0,0, in the left image. The Y and X coordinates mark where the light will move if you slide that light's coresponding Transform(Movement) Dial posotively or negatively. Once the the Y position has been moved from 0 the Z Transform dial becomes functional. The Z Transform Dial will force the light to circle around the Y=0 point, 360 degrees. As shown by the contrast between image 2 and 3 the more the Y Transform is offset from 0, the Larger(And we'll get to this in an argument...) distance the Z's Transorm Dial's 360 degrees will actually cover. = )


cainbrogan ( ) posted Sun, 22 December 2002 at 8:58 AM

file_37496.jpg

In order to copy the Bryce model I added as many lights adjacent to a light at 0,0,0 as I could. The result was 6 new lights(The pink ones.) I then counted how many lights I could stack from 0,0,0 before I place a light on the Y's 90th degree equator. The result was 4(As represented in the differentiating color scheme.) So, as you can see, in the images above, I added 4 rows of 6 lights to the light at 0,0,0, to form a half-dome/sphere of Global Illuminmation.

Finally, before I set each row and each light in each row uniformly seperate, I'd like to critique this model and get any feedback anyone may have. I believe there is more light per sq. inch at the top of the dome. Therefore the lights at the top of the dome will need to be dimmed. I have a couple Pythons I was given with falloff and brightness value/percentage functions which will effect all of the lights at once, but I'll be horn swaggled to think there is'nt a more uniform way to just covere the surface of this sphere with lights. My problem is I ca'nt think this through mathmatically. Can anyone visualize, or know, of how this could be accomplished, in order to have the same # of lights per square iota of globe surface at any given square surface coordinates?

= )


Chris ( ) posted Sun, 22 December 2002 at 9:19 AM

sounds interesting :) do you have a testrender with that lightset? Chris

"It Is Useless To Resist!" - Darth Vader


cainbrogan ( ) posted Sun, 22 December 2002 at 9:43 AM

Not just yet, but I promise to post one before I'm finished with this thread. I even have a Pythons, from Ockham, that will set all of the lights to the color and intensity of the selected light. I need to get handy with Python though. I just requested, of him, a Bi-Polar Falloff Python. The falloff script he's given me is Uni in that it's changes will affect whichever light is selected, as a pole, then increas or decrease it's change as it moves towrd the opposite pole. I figure there is X too much light at 0,0,0 and it's opposite pole, and Y(0) just the right light at the equator. Therefore a falloff Python with a -100 to 100 parameter, set to -50(With the light at 0,0,0 selected), should cut the lights at either pole in half, and then leave the lights at the equator alone...At least I think cutting each pole by 50% is whats called for...Anyhow this would be how you could run the falloff script so as not to effect beyond the equator. = )


cainbrogan ( ) posted Sun, 22 December 2002 at 9:45 AM

I'd also like to spend some time perfecting the spacing between the lights in the set. Right now they are all present and roughly in thier correct spot, but not mathmatically... = )


Chris ( ) posted Sun, 22 December 2002 at 9:47 AM

oh man ... that sounds all greek for me :) I think I have to more into that light things :) looking forward for your testrender :) Chris

"It Is Useless To Resist!" - Darth Vader


Momcat ( ) posted Sun, 22 December 2002 at 10:17 AM

^_^


TrekkieGrrrl ( ) posted Sun, 22 December 2002 at 11:04 AM

Uhm... included with the V3 hair (I think it was with the ha at least) there's a Global illumination light. Works really good and looks something like yours, only with all the lights set to a fairly dark grey.

FREEBIES! | My Gallery | My Store | My FB | Tumblr |
You just can't put the words "Poserites" and "happy" in the same sentence - didn't you know that? LaurieA
  Using Poser since 2002. Currently at Version 11.1 - Win 10.



ronstuff ( ) posted Sun, 22 December 2002 at 2:11 PM

so far so good :-)


cainbrogan ( ) posted Sun, 22 December 2002 at 2:36 PM

ernyoka1 - Did V3 hair come with V3, or was this a seperate puchase? = )


quixote ( ) posted Sun, 22 December 2002 at 3:03 PM

!

Un coup de dés jamais n'abolira le hazard
S Mallarmé


AgentSmith ( ) posted Sun, 22 December 2002 at 3:12 PM

Looks sound to me cainbrogan. I always made global illumination in Poser just by splittlg the degrees, basically a light placed every 22.50 degrees in every direction. When I went larger, every 11.25 degrees. Of course to do all this, you have to type it all in with the dials. But, as you mention, the rub is always that point where the lights converge, and there is too much light. AgentSmith

Contact Me | Gallery | Freestuff | IMDB Credits | Personal Site
"I want to be what I was when I wanted to be what I am now"


AgentSmith ( ) posted Sun, 22 December 2002 at 3:14 PM

file_37497.jpg

22.50, 45.00, 67.50, 90.00, etc.

Contact Me | Gallery | Freestuff | IMDB Credits | Personal Site
"I want to be what I was when I wanted to be what I am now"


AgentSmith ( ) posted Sun, 22 December 2002 at 3:18 PM

To help with the problem of too much light, I would just change the intensity of the lights as each level went up, the bottom level was at 100%, then 90, 80, 70, 60 and the top one light at 50%. It's definetly not the true solution, but it helped somewhat. AgentSmith

Contact Me | Gallery | Freestuff | IMDB Credits | Personal Site
"I want to be what I was when I wanted to be what I am now"


cainbrogan ( ) posted Sun, 22 December 2002 at 3:57 PM

AgentSmith - Ockham is definatley the man to honor here, as I explained, the fallof Script he gave me does that changing from any selected pole. Moreover Ockham just replied with the Bi-Polar Intensity and Color Falloff Script I mentioned! Then he informed me Python should be able to space lights perfectly. I just requested he try this, and asked if it could determine the max. number of lights, if it could determine which numbers of lights would fit best denominatorily(You know when you hae to find a common denominator to fit fractions into for some mathmatics,) or if we could try both? = )


AgentSmith ( ) posted Sun, 22 December 2002 at 3:59 PM

Cool beans, making 3D a better, brighter place, lol. Would love to see your results one day! AS

Contact Me | Gallery | Freestuff | IMDB Credits | Personal Site
"I want to be what I was when I wanted to be what I am now"


cainbrogan ( ) posted Sun, 22 December 2002 at 4:01 PM

Once this(these) new light set(s) are finished, I'll have the superb oppurtunity to sit down with all of his Pythons and become much more familiar with thier useage. I'll then be able to better tell of each, and maybe write a few tuts! = )


hauksdottir ( ) posted Sun, 22 December 2002 at 4:49 PM

Getting things evenly spaced is known mathematically as a "packing problem". I know there are formulas for covering an entire sphere with evenly placed centers for much smaller spheres, which would eliminate your convergence problem and the resultant need to modify each and every light source's strength. That particular reference was in a ScienceNews article a couple years back, so I don't have it at my fingertips. A web search on "packing problem" ought to turn up this example though. Carolly


lmacken ( ) posted Sun, 22 December 2002 at 7:29 PM

Attached Link: http://www.applied-synergetics.com/ashp/html/domes.html

Search on 'geodesics.' R. Buckminster Fuller worked all this out in Synergetics. You could scale a geodesic sphere up to the radius you want the lights at, and place one light at each vertex. You can get Dome 4.80, a utility to generate any arbitrary sphere at http://www.applied-synergetics.com/ashp/html/domes.html. Thanks for asking.


cainbrogan ( ) posted Sun, 22 December 2002 at 8:31 PM

Ockham just delivered his CreateLights.py. I am surrently testing it for sweet spots. My suspicions of needing the right common denominators was right. I may have also found a bug. I'll post my results once I have a few things to show! = )


cainbrogan ( ) posted Mon, 23 December 2002 at 12:55 AM

file_37498.jpg

Well I found some bugs in the first version of Ockhams Global Illumination Python, but here are some shots of a few interesting sets. They need some refining though. The total light count does'nt reflect the number of rows evenly. That is you ca'nt divide the toal number of lights, by the number of rows and expect a whole number, I'll be working on that later today. I'll keep everyone posted as we go... = )


AgentSmith ( ) posted Mon, 23 December 2002 at 2:01 AM

LOL..o my god that's a lot of lights.... Keep us posted o masochistic renderer. ;o) AS

Contact Me | Gallery | Freestuff | IMDB Credits | Personal Site
"I want to be what I was when I wanted to be what I am now"


cainbrogan ( ) posted Mon, 23 December 2002 at 2:16 AM

I'm going to chip away at the 342, but with Ockham's Python it was so easy to do, I had to try it! I'll be back with more! = )


movida ( ) posted Mon, 23 December 2002 at 7:08 AM

.


hauksdottir ( ) posted Mon, 23 December 2002 at 8:22 AM

342 lights?!? What are you doing... Gandalf at the bridge?


PheonixRising ( ) posted Mon, 23 December 2002 at 11:07 AM

Um.... do you guys mind not disecting my light set? Thanks. Anton

-Anton, creator of ApolloMaximus: 32,000+ downloads since 3-13-07
"Conviction without truth is denial; Denial in the face of truth is concealment."



NEW The Poser FaceInterMixer


cainbrogan ( ) posted Mon, 23 December 2002 at 1:51 PM

hauksdottir - Thanks for posting, would you elaborate on ".", with maybe a full letters, a word, or more? Gandolf at the Bridge...Haha! No, like I said this Python is so easy to use, I tried 360, to see what would happen, and this was the result. Pretty interesting though no? I'm putting together a small render farm, and should be able to do some...testing with it, eventually! PheonixRising - Actually you had nothing to do with this effort...untill now. These sets were created entirely by myself with Python Scripting from Ockham. They may or may not make it to the Marketplace. I'll be need some Advertising/Free Content for my site as soon as I larn how to use IIS. Though I did just check out your Artist Page and DL'd the sets I believe you are refering to. = )


volfin ( ) posted Mon, 23 December 2002 at 4:37 PM

.


cainbrogan ( ) posted Mon, 23 December 2002 at 4:46 PM

Is this just to get updates for this post? = )


AgentSmith ( ) posted Mon, 23 December 2002 at 6:13 PM

Yes.

Contact Me | Gallery | Freestuff | IMDB Credits | Personal Site
"I want to be what I was when I wanted to be what I am now"


PheonixRising ( ) posted Mon, 23 December 2002 at 8:17 PM

I created the lightsets for Daz described above. I am sure you have done this on your own. But then the details on my lights mentioned here in the pics and post above is what I am refering to. Anton

-Anton, creator of ApolloMaximus: 32,000+ downloads since 3-13-07
"Conviction without truth is denial; Denial in the face of truth is concealment."



NEW The Poser FaceInterMixer


cainbrogan ( ) posted Mon, 23 December 2002 at 8:40 PM

Why were you thinking we were going to dissect anything? I'd appreciate a few posted pics of your light sets, as I asure you none of the images I've posted were of your work. BTW - Do they come with V3, or are they a seperate purchase? Any product links would be nice! = )


PheonixRising ( ) posted Mon, 23 December 2002 at 8:45 PM

http://store.daz3d.com/catalog/product.php?pidx=1944&paridx=151 Post #13

-Anton, creator of ApolloMaximus: 32,000+ downloads since 3-13-07
"Conviction without truth is denial; Denial in the face of truth is concealment."



NEW The Poser FaceInterMixer


volfin ( ) posted Tue, 24 December 2002 at 10:03 AM

Anton, I think they are talking about the Global light that came with the Bombshell hair for Vicky 3. Anyway, doesn't matter.


PheonixRising ( ) posted Tue, 24 December 2002 at 2:36 PM

I made those lightsets

-Anton, creator of ApolloMaximus: 32,000+ downloads since 3-13-07
"Conviction without truth is denial; Denial in the face of truth is concealment."



NEW The Poser FaceInterMixer


cainbrogan ( ) posted Tue, 24 December 2002 at 7:31 PM

file_37500.jpg

Poor Anton, thinks he's getting ripped off...

Well, I've been giving our Pythons some thought, and have come up with a couple new premises. The first was to set the top light, of the set I have thats very similar to post #13, to half of what the values of the lights at the equator are. And then transfer that gradient change through the rows of lights in between. Lets say the equatorial row is at a value of 160. Because I see the that row as half way away from the over powered lights at the top of the sphere, I'd change the top lights to 80. The differeance there was 80. 80 iotas divided by 4 rows(From the N. Pole.) equals a gradual change of 20 per row(See above pic.) The only problem I see with this at this change needs to be dynamic. If I were to use Ockhams LightIntensity.py(Which changes all lights a given percentage.) the aspect ratio between the rows would change. Thus I'm inclined to aquire a new script, just for this set, that will changes the color or intensity of all the lights at once, but at the ratio mentioned in my previous example!

My other premise has to do with dice, particulary those used by people familiar with the role playing game Dungeons and Dragons, in which 4, 6, 8, 10, 12, 20, and 100 sided dice are used. Any of the dice can be enclosed in a perfect sphere so that each point of the die makes contact with the surface of the sphere. A python to generate a new die for each # number of requested lights, then make that transfer is what I've posed to Ockam last. I also suggested a toggle to keep point 0,0,0 static should be added.

= )


cainbrogan ( ) posted Tue, 24 December 2002 at 10:36 PM

I have a question for everyone. Not the picture on the right in post 2, then the pic. in post 13. To get the lights to change this way I need to move the camera's Y Orbit. But the last time I tried this I noticed I was underneath the ground plane looking up. Granted I could have turned of the ground shadow and repositioned my object, but I can think of many instances this would'nt be optional. How are light sets rotated around in general? = )


volfin ( ) posted Wed, 25 December 2002 at 7:41 AM

To my knowledge there is no way to move lights as a group. Each light would have to be moved individually using it's X/Y/Z Rotate Dials. Unless someone could come up with a Python script to do it.


cainbrogan ( ) posted Wed, 25 December 2002 at 9:02 AM

Getting back to my dice theory for a moment. What do we think would be better translating each die's sides, points, or both. Any ideas on how? I'm going to duck into my schools math lab and try to figure this out. I'd much rather have a Python to do this, for any number of lights, than just do a bunch of static sets, though any input on how the translation could come, would be appreciated! = )


FireHorse ( ) posted Wed, 25 December 2002 at 9:28 AM

.


cainbrogan ( ) posted Wed, 25 December 2002 at 12:44 PM

file_37501.jpg

I'm convinced that preparing Global Illumination models should develop from mapping the sides of dice to the surface of the sphere.

Imacen - Thanks for the link!

The first hurdle I see here is learning of how dice are created. My first hope is that a die can be generated with any number of sides greater than 4. I just posted a question about this over at the site Imacken linked to earlyer, at http://www.applied-synergetics.com/ashp/forum/viewtopic.php?p=2#2.

The second hurdle is at mapping the center of each side of each die to a coordinate on the surface of the Light Control Sphere.

While we're waiting for the more advanced formulae input of hurdle 1, let's start in on the second hurdle by taking on the 4 sided die as a warmup. In the above pic. are the images of the usual D&D(Dungeons and Dragons) dice I've been mentioning. The "4 Sided" is the one in the middle. Side 1 is easy, we can plot it at 0,0,0. But then where the other 3 lights go is questionable. My first instinct is to divide the 180 degrees, from the top of the sphere to the bottom, by the number of sides we have in the shape(180 / 4 = 45, 180 - 45 = 135.) Thus we could use the latitudinal line at 135 by dividing it's 360 degrees, of Z rotation, by the number of sides left to plot (360 / 3 = 1 light every 120 degrees.) But then I think ahead to the model of the 6 sided. The 4 planes of its "Sides" would make contact with the surface of the sphere at the equator(The 90th latitude). This makes me ask what is divided by 4 to get 90. The answer of 360, transfered back to the model of the 4 Sided, would mean we should have used the 120th line of latitude(360 / the 3 three sides of the 4 Sided = the 120 latitude). I tend to lean toward this second theory, as with it we come up with 120 degrees twice, though I'm not proof posotive that it is perfect. And would actually like a better formula, as all die shapes wo'nt be as easy as finding just one line of latitude aside from 0,0,0...

= )


cainbrogan ( ) posted Wed, 25 December 2002 at 1:31 PM

file_37502.jpg

I've been poking WinDome, the application I got from the link Imacken provided. It's a close call, but I do'nt think its made to generate dice. Take a look at the above pic. This was produced by WinDome, as a Frequency 20(20 Sided die...?) Full Sphere, but as you can see be the slight bend in the color differentiations, that this shape is balanced to roll as a die. = )


cainbrogan ( ) posted Wed, 25 December 2002 at 1:42 PM

Hmm, I should have run that highlight straight through the equator of that last example, oh well... = )


cainbrogan ( ) posted Wed, 25 December 2002 at 6:41 PM

file_37503.jpg

The height of a equilateral tringle is the length of a side times the square root of 3 divided by 2(.866 if the origional side was a length of 1.) Picture for a second the pyramid resting on its base with one of the bases points facing you. If we were to travel around the 0 line of longtitude we would pass two height lengths and one side length. 360 divided by three would be 120 per length, but remember 2 sides are .866 the 120 degrees. So really we have two height lengths that span 103.92 degrees and one side length that spans 152.16 degrees. Plotting each light to 0,0,0 and then moving it from there the 4 lights ended up at X=52, Y=0, Z=0, X=-52, Y=0, Z=0, X=0, Y=128, Z=0, and X=0, Y=-128, Z=0. But because I hav'nt found a Light Set Rotator, I then need to rotate the X axis of my Main Camera and my M2 Model -141 degrees, to get the light set to shine as in the above render.

This image was rendered with all of M2's materials set to Middle gray, and with each light set to a Middle Gray Intensity Value of 120, and with much postwork done with Photoshop's Levels

I left a few decimal points out of this explanation, but Poser has a bad habit of not keeping these exactly where you left them, so thought the set may not Perfect it's reallly close...and you can see that in many of the highlights. BTW - The postion of each of these lights is supposed to be indicative of where the center of each of the planes of the pyramid would make contact with surface of a sphere.

= )


PheonixRising ( ) posted Thu, 26 December 2002 at 3:27 AM

I do not feel that I am being ripped off but I would appreciate detailed info on the light set up not being detailed here. Saracsm isn't neccesary.

-Anton, creator of ApolloMaximus: 32,000+ downloads since 3-13-07
"Conviction without truth is denial; Denial in the face of truth is concealment."



NEW The Poser FaceInterMixer


cainbrogan ( ) posted Thu, 26 December 2002 at 10:26 AM

Then I'll let you in on whatever it is that has you spooked, but your gonna have to speak up! I told you the first set I posted was just a pyramid stacking theory, and have named the author of the script the other sets were direived from. Else, I hav'nt appreciated your entrance into this post assuming skullduggery, and ask you to retract that statement, without any basis for presumption. = )


PheonixRising ( ) posted Thu, 26 December 2002 at 12:39 PM

I never said I was addressing you. You assumed that. If you want a private post I suggest you use email.

-Anton, creator of ApolloMaximus: 32,000+ downloads since 3-13-07
"Conviction without truth is denial; Denial in the face of truth is concealment."



NEW The Poser FaceInterMixer


cainbrogan ( ) posted Thu, 26 December 2002 at 1:35 PM

As author of this post it's my pleaseure to see through its development. Anything you say in here is reply to my Subject. If you're assumptions have been dispelled, then so be it, but I request, as such, you retract your intitial entry to my discussion. Else, just do'nt say anything further if you hav'nt got anything legitimately/technically relavant to contribute. Regards, cainbrogan = )


cainbrogan ( ) posted Thu, 26 December 2002 at 8:02 PM

file_37504.jpg

This one was a give me. Again I just kept plotting 0, 0, 0, and then moving from there. You only need to move one parameter of each light. The moves were to X=180, X=90, X=-90, Y=90, Y=-90. Then I put 0, 0, 0 back to represent the 6th light.

I've noticed from experience it's best not to make mug shots. M2 is a man, and deserves ambidextrous lighting, so I've roted he and the main cam 45 degrees, a light on either side of him, rather than one overpowering lamp directly in front of him.

I'm a little partial to the first render of this set though. I think that is because of the high position of the lights in fron of him vs. this render which has lights about mid waist. I was going to do a little more rotating, but the M2 model was'nt taking too kindly to my not having a Python for light set rotation...

Next is the 8 sided...

= )


cainbrogan ( ) posted Thu, 26 December 2002 at 9:07 PM

Here's the 8 sided die. Kind of a cross between 4 and 6. I really lik the lighting of the upper half of M2 in with D4... = )


cainbrogan ( ) posted Thu, 26 December 2002 at 9:09 PM

file_37505.jpg

Here's the 8 sided die. Kind of a cross between 4 and 6. I really lik the lighting of the upper half of M2 in with D4. Again this image was render with all lights at %100, %50 intensity, with all M2's MATs set to middle gray. = )


  • 1
  • 2

Privacy Notice

This site uses cookies to deliver the best experience. Our own cookies make user accounts and other features possible. Third-party cookies are used to display relevant ads and to analyze how Renderosity is used. By using our site, you acknowledge that you have read and understood our Terms of Service, including our Cookie Policy and our Privacy Policy.