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VUE
10-05-2016, 11:59 PM
Hi all,


I was doing some test using instancing and I faced some issue that I thought is really strange, and tried to solve but to no result.

LW Version: 11.5.1
Test: Droplets on a can.

I was instancing some droplets around a can and doing all the settings right. Got what I wanted and saved the scene, even left it over night to render. Got what i want in the morning, resaved and closed the scene. Later the day, i opened the same scene... all the positions of the droplets that i had done were completely changed! I thought i might had saved the wrong scene thus did another new setting. Brought home to continue and again re-render the scene. Went to office, opened the same scene and the positions of all the droplets changed positions again! I tried another time, is the same issue. What happened? and anyone faced such problems? I had tried 3 times and they appeared this way. that is all settings in the panel remained the same but the positions of the subjects i instanced completely change. Luckily it was just some tests, i couldn't imagine is actual job i will be in big problem.

Regards.

prometheus
10-06-2016, 12:34 AM
Hi all,


I was doing some test using instancing and I faced some issue that I thought is really strange, and tried to solve but to no result.

LW Version: 11.5.1
Test: Droplets on a can.

I was instancing some droplets around a can and doing all the settings right. Got what I wanted and saved the scene, even left it over night to render. Got what i want in the morning, resaved and closed the scene. Later the day, i opened the same scene... all the positions of the droplets that i had done were completely changed! I thought i might had saved the wrong scene thus did another new setting. Brought home to continue and again re-render the scene. Went to office, opened the same scene and the positions of all the droplets changed positions again! I tried another time, is the same issue. What happened? and anyone faced such problems? I had tried 3 times and they appeared this way. that is all settings in the panel remained the same but the positions of the subjects i instanced completely change. Luckily it was just some tests, i couldn't imagine is actual job i will be in big problem.

Regards.

I think you need to provide more info about the instances, are they applied on particles, points, or by surface, polygons? mainly the distribution part.

VUE
10-06-2016, 01:10 AM
I think you need to provide more info about the instances, are they applied on particles, points, or by surface, polygons? mainly the distribution part.

Sorry i miss out those points.

Thanks for reminding.


1) They were applied on surface under Type, Distribution is Random and no relax. Surface name is All.
2) Each drop has 60 polygons count, after sub-patched is about 400 polygons
3) Number of instance are 2500, 1 drop of design weight is at 90%, and another at 10% (trying to create random feel)
4) Alighment is Normals
5) Scale is Random at 20% min and 80% max

Regards

dpont
10-06-2016, 04:26 AM
If your surface is subpatched,
you may have different level between preview (including VPR) anf render,
and different geometry gives different distribution.

Denis.

VUE
10-06-2016, 04:52 AM
Hi All,

I made a mistake that is... I didn't render to double confirm that the distribution of the droplets that I see on the camera view is the same as what is going to be rendered. Which means, all the while the renders will be and are the same (if I render them to check), but what I saw on the screen isn't what im getting later. What is going on? This shouldn't be the way... every time I opened the scene is going to be different distribution?

Hi dpont, I think that was what is happening. But is a little different, all my scenes i maintained the same sub-patched level. The problem is only when the scenes are re-opened later or on another machine, the distributions look totally differently (Although it will be the same if I render).

Question

1) What can be done to ensure that what im seeing will be rendered exactly the same? It will be a problem using it in the actual works.


Regards

VUE
10-06-2016, 05:30 AM
For the benefit of others to understand better. Did a screen grab.


http://i1383.photobucket.com/albums/ah297/Pixelflux/Droplets_zpslgiicpav.jpg (http://s1383.photobucket.com/user/Pixelflux/media/Droplets_zpslgiicpav.jpg.html)


Left was the actual render and right was what I saw in the camera's view. This camera's view was what was
changing (The distribution) everytime when I open the scene without adjusting anything. So as you can see, the actual render is
totally different.

dpont
10-06-2016, 05:42 AM
You spoke about the subD level between your scenes,
but what are the two level in the Object property panel
preview and render?

Denis.

VUE
10-06-2016, 09:06 PM
Hi dpont,


They are the same. Nothing was adjusted before the render.

In the Camera's view, Right (preview panel): Can Sub-D at 5, Droplets Sub-D at 3
In the Render, Left (preview panel): Can Sub-D at 5, Droplets Sub-D at 3

If this is what you are referring to?

Regards

jeric_synergy
10-06-2016, 09:16 PM
VUE, I believe Denis is referring to the subd level of the Layout render, versus the subd level of the interface. IOW, this setting:
134721
If there's a discrepency, that might account for the difference you are seeing. Here, I've set the Display to level 0 for speed of interaction, and Render to 3.

Shorter: set them to the same level, and see if it is more accurate.

Also, if you are using any kind of RANDOM setting, be sure to give it a SEED VALUE if that's an option. Some programs interpret "0" as "use any old number for the seed", which of course does not aid in repeatability.

VUE
10-06-2016, 09:56 PM
Thank you so much Jeric! I will do some tests and update you guys soon.

VUE
10-11-2016, 11:01 PM
Hi All,


Sorry for the very late update.


I've done what was told, and that was to set the "Display SubPatch Level" and the "Render SubPatch" under the object's property the same settings.
Every thing seems all ok, as I did a fast test between 2 computers (Will try on further). But i believe this is solving it.

Thank you dpont and jeric_synergy. Thanks to prometheus too. You guys are sincerely helpful.


Regards.