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MUCUS
01-23-2016, 05:21 AM
Hi Guys! :)

I was VPR testing a scene, and find out how the "use transparency" option could give a nice colour touch to the scene with radiosity (yes after 15 years of Lightwave, it's about time!!)
However, when I F9 the scene, there is no colour and the render seams to not take the glass colour into consideration...any idea about this?

132031

prometheus
01-23-2016, 05:59 AM
Hi Guys! :)

I was VPR testing a scene, and find out how the "use transparency" option could give a nice colour touch to the scene with radiosity (yes after 15 years of Lightwave, it's about time!!)
However, when I F9 the scene, there is no colour and the render seams to not take the glass colour into consideration...any idea about this?

132031

yeah..there are some issues with vpr not rendering exactly what final render does, will have to wait until lw 2016 where the vpr and final will be the same I reckon, however..first you need to check if vpr settings is set to srgb as you have in final render...I think the final render is correct, and you may have a different color space for vpr? could be wrong about that..not sure about use transparency though..might need to check it.

I discovered another issue of not rendering equally, when using radiosity in draft mode in vpr and with fine mode..completly different results...but thatīs probably another issue.

prometheus
01-23-2016, 06:06 AM
The limitations in VPR are as follows...Note Draft limitations....so for getting more accurate VPR representation according to final render, try uncheck VPR draft...maybe you did? but got the issues anyway?

But actually it seems the final render is correct, and taking in account the bluer tones from the sky, and not the other way around ..you say the f9 isnīt correct, but I think it seems correct..the vpr isnīt in my opinion.

from manual...

VPR
VPR Draft Mode Limitations
VPR’s default Draft Mode is designed to show you renders as quickly as possible, however it doesn’t
support everything that VPR is capable of. Here’s a list of VPR Draft mode limitations:
• Photoreal Motion Blur is disabled
• Depth of Field is disabled
• Advanced/custom cameras are disabled
• Stereo rendering is disabled
• The adaptive threshold is set to 0.1
• Minimum Samples is set to 1 and Maximum Samples is 9
• Oversampling is set to 0.5
• Undersampling is set to 4 pixels max (disabled in full rendering)
• Adaptive Sampling uses a 2.2 gamma function rather than the output color space to
determine the brightness difference.
• Shading Samples are limited to 4.
• Ray Recursion Limit is set to 4 but the maximum reflection rays is set to 2.
• The max GI ray bounces is set to 1
• The GI Use Transparency, Directional Rays and Use Bumps setting are disabled.
• The GI Rays Per Evaluation setting is limited to 32/16 when interpolating and 4/4 when
sampled.
As you can see, to get a true view of your render, better to get out of Draft mode as you are nearing
project completion, especially if you are going to require an F10 render sequence and want no
surprises because your rendered images don’t look the same as your VPR previews.

zapper1998
01-23-2016, 06:10 AM
darn....
yep, forgot all that was disabled..

but also I noticed I had VPR going on all 4 views and was surprised all 4 viewports where VPR, hmmm, did not know we can have all view ports in VPR.. interesting..

MUCUS
01-23-2016, 06:29 AM
Prometheus, maybe you're right, and F9 render is correct. When I uncheck "use transparency", VPR and F9 are exactly the same, that's why I was saying that F9 doesn't seams to use "use transparency" ... too bad I think, as it allow some nice colour effects!

prometheus
01-23-2016, 08:17 AM
darn....
yep, forgot all that was disabled..

but also I noticed I had VPR going on all 4 views and was surprised all 4 viewports where VPR, hmmm, did not know we can have all view ports in VPR.. interesting..

yes...multi viewports in vpr ...that is a good implementation, and to add to that..multi cam viewports if you want...with vpr active at the same time...so that is some nice small additions I like in the staging setup working in lightwave.


Prometheus, maybe you're right, and F9 render is correct. When I uncheck "use transparency", VPR and F9 are exactly the same, that's why I was saying that F9 doesn't seams to use "use transparency" ... too bad I think, as it allow some nice colour effects!


Yeah.but you might want to think not only nice color effects just like that, but what is actually causing the color effects etc, so maybe track exactly what is coloring the scene, probably the main color you initially had applied in the surfaces..or lights in the scene with some dedicated color, otherwise it is the surrounding environment, backdrop gradient..or if you use sk_sunsky.

Edited...in your case I can see the color is a bit pinkish on the surface..that is overriden by the environment light or gradient from the sky when radiosity illuminates it..like in the real world.

Additional tip..
if you want volumetric lights together with dp_sunlight..add a point light and "m" for motion and use the sk_sun motion modifier, (not the sunspot modifier) then you use the sk_sunlight rotation and the volumetric light should follow, you would have to correct density and radius of the volumetric light though..to fit your scene..can be a bit tricky at first.

prometheus
01-23-2016, 08:29 AM
another tip..

with dp sunsky, you can tweak in the color flooded in a room with all kinds of settings, choose preetham instead of hosek wilkioe, change turbidity..brightness etc, or in the conversion tab, change to other color systems...but you also have to be aware of initial surface color and how that mixees together.

MUCUS
01-23-2016, 09:41 AM
Thank you prometheus for all the tips! I'm working with classic area light and dp sky environment for the backdrop.
In the first image, the pink colour is due to the color of the glass...as it has 200% luminosity
(yeeeeeeeah I know I know, real world don't get that, but I love this kind of stuff in Lw haha)
it's spreading light and glass colour on the wall, but only with VPR with "use transparency"

Well anyway, thank you for the tips!

prometheus
01-23-2016, 12:37 PM
Thank you prometheus for all the tips! I'm working with classic area light and dp sky environment for the backdrop.
In the first image, the pink colour is due to the color of the glass...as it has 200% luminosity
(yeeeeeeeah I know I know, real world don't get that, but I love this kind of stuff in Lw haha)
it's spreading light and glass colour on the wall, but only with VPR with "use transparency"

Well anyway, thank you for the tips!

I thought it was the surface color, didnīt notice it was the glass color.

spherical
01-23-2016, 07:00 PM
Additional tip..
if you want volumetric lights together with dp_sunlight..add a point light and "m" for motion and use the sk_sun motion modifier, (not the sunspot modifier) then you use the sk_sunlight rotation and the volumetric light should follow, you would have to correct density and radius of the volumetric light though..to fit your scene..can be a bit tricky at first.

Can you elaborate on this, please? :)
Point Light position is where? sk_sun position?
Can a Spot work?

prometheus
01-24-2016, 09:03 AM
Can you elaborate on this, please? :)
Point Light position is where? sk_sun position?
Can a Spot work?

not sure about the spotlight, I use a point light since it goes in all directions, think it might be harder to control the radius, cone, falloff etc with a spot light.

might need to record it.
but itīs quite simple, just add a point light, enter motion tab for it, add the sk_sun motion modifier from dpont, it should then adapt the sk_sunlight rotations so the volumetric beams from the point light follows the sk_sun manual rotation..if you have set the sk_sun to manual that is...but how much the effect of volumetrics is seen, that depends on the radius of the volumetric light and also the settings of the distance in the sk_sun motion modifier...as well as the actual density of the volumetric light and luminosity...If I have a ground or a floor, I would exclude the volumetric light in that objects panel, since I would only want the sk_sun softer 0.52 angle on the floor, there is no volumetric light that is sampled with soft shadows, so that is why I exclude it and only let it serve as casting rays and volumetrics on the floor.

doesnīt matter where the point light is in the scene, or the actuar sunlight (sk_sun) once the motion modifier is applied on the volumetric point light, it will adapt the rotation (also position) value of the sk_sunlight, so I can rotate the sunlight as I want and the volumetric follows.

I really hope the lw team manages to implement a better true volumetric sunlight in the next version though...so we donīt have to go through hops of setting up stuff and excluding lights etc.

spherical
01-24-2016, 04:41 PM
Ok. I think I've got it. Pretty neat trick. Thanks!

prometheus
01-24-2016, 09:52 PM
Ok. I think I've got it. Pretty neat trick. Thanks!

For indoor scenes...
great...I recommend to exclude the volumetric light from the floor if you want beams through windows for instance, you already got the main sunlight taking care of the lighting, you only need the volumetric ray density...otherwise it might override the sk_sunlight softer light angle...so in your floor object properties ..if that is the floor object so to speak, exclude the volumetric light.

It would be nice to have an ideal volumetric radius setting, balanced in relation to the sk_sun motion distance...for large environment scenes you would need a larger volumetric light radius..several km.
One would also most certainly need to balance density, luminosity depending on radius etc.

For outdoor scenes...
I got it working pretty nicely with a very large skydome object ..which I then mapped a nice cloud texture on, that is serving as the sky..then I copied the dome, but scaled it down a bit, parented it to the first dome..now the second smaller dome is then remapped to have the cloud texture in the transparent channel...so if you set this up correct..you can have godrays shining through the transparent dome, and it cast soft shadows and it reacts pretty nice when I rotate the main skydome...itīs a great way to add dramatic shadows to a scene,and at the same time get sunbeams shining through.

One could probably use hypervoxels of course..on particle fields, but I am not going that route until the next lightwave version....the mix of hypervoxels and volumetric lights are just too darn slow as it is now...hoping for a better volumetric sunlight without the need to mix two lights, and I am hoping for that sort of light to work much faster with volumetric voxels than before.

spherical
01-25-2016, 01:24 AM
For outdoor scenes...[/B]
I got it working pretty nicely with a very large skydome object ..which I then mapped a nice cloud texture on, that is serving as the sky..then I copied the dome, but scaled it down a bit, parented it to the first dome..now the second smaller dome is then remapped to have the cloud texture in the transparent channel...so if you set this up correct..you can have godrays shining through the transparent dome, and it cast soft shadows and it reacts pretty nice when I rotate the main skydome...itīs a great way to add dramatic shadows to a scene,and at the same time get sunbeams shining through.

Holy Crap! Cool technique. Ok, I gotta carve out some time to try to replicate this. Problem is, my SO decided that she'd follow my lead of falling face-first into a box of large, thick blown glass planet orbs; shattering a 14cm Saturn with my skull, by her stepping on/through a rotten board on the deck on her way to the media blasting cabinet to etch some blown glass pet memorials. Went down like a sack of potatoes. Now we are monitoring each other's concussions. And we were planning to go see Star Wars this week. Can't have a lot of brain stimulus or risk swelling. Dammit!

prometheus
01-25-2016, 04:38 AM
Holy Crap! Cool technique. Ok, I gotta carve out some time to try to replicate this. Problem is, my SO decided that she'd follow my lead of falling face-first into a box of large, thick blown glass planet orbs; shattering a 14cm Saturn with my skull, by her stepping on/through a rotten board on the deck on her way to the media blasting cabinet to etch some blown glass pet memorials. Went down like a sack of potatoes. Now we are monitoring each other's concussions. And we were planning to go see Star Wars this week. Can't have a lot of brain stimulus or risk swelling. Dammit!

LOL...Yeah, you should not risc further braindamage with too much hazzle with volumetrics in lightwave..I might start a new thread on it, with some hints.

hereīs some samples..mostly just draft renders..and one is an actual 100% hypervoxels clouds and volumetric lights, think I am getting a bit more confident on what is needed to get a decent look, though it will still take time to render ..at least for true volumetrics with hypervoxels on particles like in this first image, the others with shrox nice dante ship, that is just two skydomes, one with the actual colored mapped cloud, the other is just mapped the same but on the transparency channel on another skydome..slightly smaller than the other, not sure that would actually be necessary to have it smaller though, would like to find out if thereīs any good animated cloud map, that would look cool once mapped and once the volumetric is set up, so the beams slighly changes as the cloud moves accuratly.


oh...my uploads was messed up..will have to post later..in a dedicated thread maybe..got some other business to do first.

prometheus
01-25-2016, 09:03 AM
spherical..you might want to check this thread...posted some new samples there, the first is pure hypervoxels with volumetric lights though, the others are just two skydomes...

http://forums.newtek.com/showthread.php?146615-Atmospherics-with-dpont-sunsky-sprites-soft-cloud-whisps-fog-and-related&p=1463606#post1463606

spherical
01-25-2016, 07:29 PM
I'm on it. Thanks!