Hi all,

If certain part of a figure is covered by a cloth and I make this part invisible, would this decrease the overall rendering time?

Thanks in advance

Under some circumstances. Tell us which version of Poser you're using at the very least.

Hi cspear, 

I am using poser 7 sr4.

The overall benefit to render time would largly depend on you render settings and the complexity of the materials.

If for example you're using complex shaders for your skin then covering them with clothes could speed up things. But if the skin texture is simple it won't help much with render times.

Making parts invisible inside clothes won't do anything if you're using P7. But could help in later versions if you have SSS applied because it appears that SSS is calculated for materials even if they are behind clothing.

I did an experiment, using Poser 7.

I took the scene that I used to render my avatar, and timed the second and third renders at around 127.5 seconds. The first render was a second or so slower due to the loading phase taking longer. "My" glasses' lenses use refraction so they take a while to render.

Then I positioned a plane in front of the scene so it blocked off all of the camera's field of view. Renders now ran at around 21-22 seconds.

I made everything in the scene invisible apart from the plane. Renders now took 8 seconds or so. Conclusion: in Poser 7 at least, hiding elements that the camera can't see will cut your render times. It may or may not be worth doing according to other factors. Try it for yourself! I used svdl's timedrender script to tell me how long renders were taking.

I ran another render with the hidden parts deleted from the scene, i.e. with the plane only. That was about the same speed, so as far as the renderer is concerned, hiding an object is the same as it not being there.

I stand corrected.

Is having a character "off screen" the same as not being there at all in realtion to render time?

And is an "invisible" character the same one not there in this respect?

The point is, is there an advantage in deleting a character from a scene over just making it invisible (once the textures have loaded)? I guess there isn't accoring to your trial.

I didn't try pointing the camera elsewhere - I'll run that test when I have a moment. I usually make off-stage stuff invisible unless it's supposed to contribute shadows or reflections, but I don't know for sure if there's an advantage.

According to my test, in rendering terms there's nothing to be gained by deleting unseen items as opposed to making them invisible. Looking at the bigger picture, hidden items will contribute to other factors like file size, loading time and memory use, of course. I usually hide things until I'm sure I no longer want them in the scene, then I delete them. Then I discover I did want them in the scene after all. :)

Depending on your hardware set up, couldn't the amount of memory a scene takes up affect the render time?

Thanks Bob, this is interesting stuff! :thumbupboth:

My own experience (lately I've been rendering scenes with many characters and things in them) is that so long as the thing is out of view (and this includes raytracing, so just moving it off to the side out of camera view won't work if you've got reflections that could see it) the render speed is reduced pretty much to the same as if you deleted it from the scene entirely.

I've got scenes where, if I don't need a character or object for that particular render, I move them outide the room, or drop them below the floor, or stuff them into a nearby wall or column to get them out of the way. Or simply make them invisible, either entirely, or to raytracing and/or the camera.

I haven't had to do it lately, but with my old computer/older version of Poser, I would routinely turn off body parts that weren't showing.  There were some scenes that wouldn't even render unless I did that.

I can't answer the memory question definitively, but I think as long as you have enough for the scene, then other factors will probably take precedence. My laptop with 2GB RAM and a dual-core 2.1GHz Pentium is a good 50% faster at rendering my avatar than the system I used earlier in the thread, which had 4GB RAM but only a single-core AMD processor rated at 2.8GHz. Both were running 32-bit XP. A more complex scene may well give different results.

Moving on to camera moves, it does seem that the renderer still refers to off-camera objects in some way. Renders sped up if the camera pointed away from the complex parts of the scene, but were slightly faster still if those objects outside the camera's field of view were made invisible.

Also, my habit of surfing the net while waiting for a render to finish adds time as well. But I knew that already. :) 

Would you say that deleting off camera objects world be even more advantageous than just making them invisible with respect to speed and memory use?

In Poser Pro 2010, if a whole character or prop is invisible, it doesn't seem like Poser loads their textures into the calculations when rendering the first time - which could speed up the initial render. But, if you had any part of their body showing, I think Poser calculates their entire texture collection.

Back in the Poser 5 era, I could have sworn Stewer did mention that making elements invisible that were out of the camera's view did help lighten rendering processes.

Quote - Would you say that deleting off camera objects world be even more advantageous than just making them invisible with respect to speed and memory use?

There's no advantage with respect to speed, as far as I can see. There should be a reduction in memory use, although you may not see the full benefit until you've restarted Poser.

Quote - In Poser Pro 2010, if a whole character or prop is invisible, it doesn't seem like Poser loads their textures into the calculations when rendering the first time - which could speed up the initial render. But, if you had any part of their body showing, I think Poser calculates their entire texture collection. Back in the Poser 5 era, I could have sworn Stewer did mention that making elements invisible that were out of the camera's view did help lighten rendering processes.

If you think about it, the renderer needs to assume that every visible scene element is going to taken into account during rendering. Even if the camera isn't pointing at it, it may feature in reflections, or any other indirect effect that can now be achieved in Poser. But if you turn off an element's visibility, the renderer knows from the start that it can ignore that thing. Hence the resultant speed-up. Now that later versions don't load unique textures for invisible items either, there should be an improvement in memory usage also.

When I was doing the tests I mentioned in my first post in this thread, with the plane in front of my avatar figure, I noticed that the rendering slowed down when it reached the point where the glasses were - as it does when they're visible. It's as if it had to stop at every pixel and check whether whatever was behind the plane ought to figure in its calculations, and that took extra time. What's more, the time depended on the nature of the material, even though it was hidden. The renderer couldn't "look ahead" well enough to work out that the things behind the plane would never have any bearing on the final render.

In conclusion:

Make any scene elements that have no contribution to the final render invisible; it will speed up the rendering, and may help memory usage too.

(Edited for clarity. I hope.)