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3D Kiwi
12-29-2013, 08:02 PM
I was wondering if someone can help me. Just getting back into LW. I have a small scene with two objects. The problem im having is when I up the shading samples in the render globals panel it affects both objects, I really only need to increace the samples on one of the objects. Is that possible? It seams to me there should be a override or something like that for each shader otherwise you would be over sampling objects or surfaces when you dont need to.

Im also getting a lot of flickering with instances in opengl. Seams to happen when you move objects or change some parramaters. I have tried it on two different PCs with different gpus. Any idea on what could be causing this. Thanks.

PS im using the 11.6 trial.

Sensei
12-29-2013, 08:15 PM
I was wondering if someone can help me. Just getting back into LW. I have a small scene with two objects. The problem im having is when I up the shading samples in the render globals panel it affects both objects, I really only need to increace the samples on one of the objects. Is that possible? It seams to me there should be a override or something like that for each shader otherwise you would be over sampling objects or surfaces when you dont need to.

No.



Im also getting a lot of flickering with instances in opengl. Seams to happen when you move objects or change some parramaters. I have tried it on two different PCs with different gpus. Any idea on what could be causing this. Thanks.

Too heavy object, I guess..
You might change Bounding Box Threshold in Display Options ('d' shortcut).

3D Kiwi
12-29-2013, 08:40 PM
Thanks for your reply. Shame about the sampling. As for the instanceing issue. I instanced a small object twice with particals. So there was the original obj (8000 polys) and then two instances of that object and it still happend when sliding the ambient intensity on the std light. Setting Dynamic update to delayed or off stopped it but surely it shouldnt have an issue with such a light scene? Im on a gtx570 with latest drivers. Other machine has a gtx 580 with older drivers.

Dodgy
12-30-2013, 03:47 AM
The unified sampling was brought in to move away from different sample settings in lights and shaders, where they were located originally, and place them in the render panel, so the sampling could be optimized and have speed increased, so it was a deliberate choice by the developers.

As to the instances, do you want me to have a look mate?

3D Kiwi
12-30-2013, 03:56 AM
Hay how are you?

I understand why they did what they did but if you could override them it would give you more control. My thinking is you wouldnt want to sample an object thats off in the background as much as you would do your hero object.

The instance problem isnt a big deal. Just trying to have a play with lw again and noticed it. Im not doing any paid projects in it just playing at the moment.

Hope you had a good xmas and have a great new year dude.

spherical
12-30-2013, 11:52 PM
I understand why they did what they did but if you could override them it would give you more control. My thinking is you wouldnt want to sample an object thats off in the background as much as you would do your hero object.

AFAIK, if an object is off in the background, it doesn't get that many samples to be concerned with. Certain lights can override the sample settings, though, and this has proven very beneficial in both speed and quality. I'm not sure that overriding samples on a per-object basis would be a good idea.

jwiede
01-05-2014, 12:20 PM
AFAIK, if an object is off in the background, it doesn't get that many samples to be concerned with.
Only really true if the object in the background is small relative to view. A large background object can still pull significantly more samples than wanted/needed, esp. with foreground object(s) that requires high sample density to render properly -- such cases nicely demonstrate why per-object/surface sample values are still useful optimizations.

jwiede
01-05-2014, 12:42 PM
The unified sampling was brought in to move away from different sample settings in lights and shaders, where they were located originally, and place them in the render panel, so the sampling could be optimized and have speed increased, so it was a deliberate choice by the developers.

IIRC, whether the sample set used varies in density across the frame based on per-object/surface/etc. settings is separate from (and irrelevant to) whether there's only one sample set used across all rendering functions requiring samples. It's the latter quality that makes it "unified sampling", the presence or absence of the former quality doesn't change that. Unified sampling just refers to a sample distribution being reused across rendering functions.

modo and Vray both use unified sampling, but allow per-object/surface/etc. adjustment of sample density within that single set's distribution.

spherical
01-05-2014, 09:51 PM
Only really true if the object in the background is small relative to view. A large background object can still pull significantly more samples than wanted/needed, esp. with foreground object(s) that requires high sample density to render properly

Yes, that's what I meant. The OP indicated that an object far away shouldn't need as many samples. This says to me that it is small and therefore insignificant. If it is large, even at a great distance, it stands to reason that it still would need many samples, no matter what. Not sampling something that is so large that when it is far away it is still large, doesn't really compute.

3D Kiwi
01-05-2014, 10:00 PM
Its more about being able to control it and optimize your renders. Currently you can only set one sample setting for all objects. While that is easy to setup its not really ideal. Just because something is large or small in the bkground isnt important. If i have a hero object in the forground and a large object that in the background and is going to be affected by say DOF in post. Im not going to need to give it the same amount of samples as the object in the forground. They way things are at the moment I dont have any options apart from maybe creating more passes.

spherical
01-05-2014, 10:17 PM
DOF is another story, granted, whether it's done in LW or in post. Some topics just get too convoluted to separate what is being discussed.

Dodgy
01-06-2014, 11:33 PM
IIRC, whether the sample set used varies in density across the frame based on per-object/surface/etc. settings is separate from (and irrelevant to) whether there's only one sample set used across all rendering functions requiring samples.

I sit corrected, but I have a vague recollection that that was the reason to remove all the sampling values from the shaders and lights.