Sponza model
- Thread starter TrevorM-L
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Thanks Al!
:smile:
:smile:
Lovely old thread, and a pretty fabulous model for test renders.
These renders are 1920x1080 and took 49s (radiosity) and 68s (falcon) on my aging Mac Pro.
I stopped Falcon at 12spp because it looked pretty good and the time was comparable to the radiosity render and I wanted to kick off a 4K render.
One skylight (more-or-less correctly rotated and with latitude and longitude to match the actual palace). Interestingly, radiosity sped up the Cheetah render by 2x (and looked a LOT nicer).
I think Falcon looks much more "photographic" even though Cheetah is actually producing equally nice, if not nicer, results in this case. The only thing that bugs me right now is the bump mapping looking nasty up close. Maybe mixing in some procedural noise would help.
These renders are 1920x1080 and took 49s (radiosity) and 68s (falcon) on my aging Mac Pro.
I stopped Falcon at 12spp because it looked pretty good and the time was comparable to the radiosity render and I wanted to kick off a 4K render.
One skylight (more-or-less correctly rotated and with latitude and longitude to match the actual palace). Interestingly, radiosity sped up the Cheetah render by 2x (and looked a LOT nicer).
I think Falcon looks much more "photographic" even though Cheetah is actually producing equally nice, if not nicer, results in this case. The only thing that bugs me right now is the bump mapping looking nasty up close. Maybe mixing in some procedural noise would help.
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I believe Cheetah with no radiosity uses the skylight's 32 samples for indirect sampling, which is quite slow.
With radiosity the light sampling is set to 1 (override) and indirect sampling is done by the irradiance cache thingy which is quicker.
In previous versions the override did not happen iirc, so if not setting the skylight to one sample manually, both algorithms got the chance to slow each other down, collectively (or something) :tongue:
Now if only we could get soft shadows from the skylight making it actually usable...
Because in Falcon the multiple importance sampling of skylight does a good job, but not so much when I introduce a second light (distant spherical area) to get realistic shadows.
Rendered with falcon, one area light (spherical with radius twice that of sun, which seems to produce appropriately softened shadows) and a hemisphere of emissive sky blue.
I also amped up diffuse reflections, but still don't get enough light in the indirectly lit areas (based on the photos I've found on Google).
Even so, looks pretty good to me. No post processing. (downsized from 2160, 100spp). No extra fill lights.
Oh, I experimented with using normal maps generated using the CrazyBump beta, but the results are to my eye inferior to the dumb "feed the image into the bump channel" trick. Then again, I don't really know CrazyBump terribly well.
I also amped up diffuse reflections, but still don't get enough light in the indirectly lit areas (based on the photos I've found on Google).
Even so, looks pretty good to me. No post processing. (downsized from 2160, 100spp). No extra fill lights.
Oh, I experimented with using normal maps generated using the CrazyBump beta, but the results are to my eye inferior to the dumb "feed the image into the bump channel" trick. Then again, I don't really know CrazyBump terribly well.
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That's impressive, I never get noise levels that low with 100 samples only.
For the blue hemisphere, a blue sky (and the cheetah skylight) always show subtle gradients in the blue, especially towards the horizon (ok that doesn't matter in case of the sponza model).
But therefore I prefer the skylight, but set intensity to zero (that eliminates the sun component but leaves the sky component untouched) and then manually push a sperical area light in the place of the skylight's little sun gizmo that appears when zooming out.
And then I found this renders more slowly then the original skylight (depending heavily on the scene, the angle etc).
It didn't occur to me to use an intensity 0 skylight. I created a hemisphere with an emissive material.
Note this image is 100spp and then downsampled by a factor of 2, so it's 400spp I guess
That said, I think I prefer the approach I took in the end because it gives me absolute control over the sky (mwahahahaha) as well as the sun (which I did in exactly the same way you describe — it's a sphere at distance 100; originally I made it the mathematically correct radius but ended up doubling it because the shadows were too hard (let's call it atmospheric diffusion fudge factor!)
E.g. I boosted the sky intensity to 1.5 which helped with the overall brightness.
I agree about the bump maps – they look both crude and plasticky (and if I were trying to impress someone I'd reframe the image to avoid them entirely; until you notice them the image is pretty fabulous). CrazyBump offers a lot of controls, but in the end I think that for better results I'd need to use a higher resolution image and probably hand-tweak the bump maps (e.g. CrazyBump will turn some crevices into "outies" no matter what I do).
Note this image is 100spp and then downsampled by a factor of 2, so it's 400spp I guess
That said, I think I prefer the approach I took in the end because it gives me absolute control over the sky (mwahahahaha) as well as the sun (which I did in exactly the same way you describe — it's a sphere at distance 100; originally I made it the mathematically correct radius but ended up doubling it because the shadows were too hard (let's call it atmospheric diffusion fudge factor!)
E.g. I boosted the sky intensity to 1.5 which helped with the overall brightness.
I agree about the bump maps – they look both crude and plasticky (and if I were trying to impress someone I'd reframe the image to avoid them entirely; until you notice them the image is pretty fabulous). CrazyBump offers a lot of controls, but in the end I think that for better results I'd need to use a higher resolution image and probably hand-tweak the bump maps (e.g. CrazyBump will turn some crevices into "outies" no matter what I do).
BTW this is Blender's Cycles in the quasi live render view with just a skylight. It definitely does a great job with shadows (Blender's 3DS import leaves a lot to be desired; C3D got all the textures and I am not up for manually setting them all up in Blender.)
That said, the skylight is way too neutral for my taste. It would take a huge amount of tweaking to make that scene look like it was really outdoors.
That said, the skylight is way too neutral for my taste. It would take a huge amount of tweaking to make that scene look like it was really outdoors.
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Last year I did some testing with Cycles on the Sponza model, there are some readily textured files out there (each having it's own unique way of assigning the textures lol).
Cycles is easier to set up with the lighting and also faster on my machine, 1024 samples (1.pic) in Cycles take 15 min vs 20 min for 1000 samples in Falcon (2.pic) being a bit noisier also.
Your shot resembles a nightly scene, of course in Cycles you could spice that up with volumetrics that are still missing in Falcon:
But the biggest advantage of Cycles so far is the possibility of GPU acceleration which makes me very curious of what your configuration could achieve, because on your blog you report to have successfully implemented a GTX 1070 on your MacPro.
Does this work with Blender in GPU mode and how much faster is it than CPU rendering?
Also I would like to hear what results Cheetah users who export to Octane could get out of the Sponza model.
I always wanted to do a walkthrough animation in HD resolution but currently neither Falcon nor Cycles would let me have it under a weeks time of rendering or so.
The new Adaptive Sampling feature is very promising, at least when we could tweak the sensitivity allowing to adjust the render to the noise reduction software of choice, that could do the trick even with Falcon on a Mac with no GPU acceleration.
And when the poll shows Cheetah users don't stick to old OS versions any more there is hope Martin can implement some Metal based advancements in the next version.
Back to Falcon as it is now, with the old Sponza model, great fun anyways:
Cycles is easier to set up with the lighting and also faster on my machine, 1024 samples (1.pic) in Cycles take 15 min vs 20 min for 1000 samples in Falcon (2.pic) being a bit noisier also.
Your shot resembles a nightly scene, of course in Cycles you could spice that up with volumetrics that are still missing in Falcon:
But the biggest advantage of Cycles so far is the possibility of GPU acceleration which makes me very curious of what your configuration could achieve, because on your blog you report to have successfully implemented a GTX 1070 on your MacPro.
Does this work with Blender in GPU mode and how much faster is it than CPU rendering?
Also I would like to hear what results Cheetah users who export to Octane could get out of the Sponza model.
I always wanted to do a walkthrough animation in HD resolution but currently neither Falcon nor Cycles would let me have it under a weeks time of rendering or so.
The new Adaptive Sampling feature is very promising, at least when we could tweak the sensitivity allowing to adjust the render to the noise reduction software of choice, that could do the trick even with Falcon on a Mac with no GPU acceleration.
And when the poll shows Cheetah users don't stick to old OS versions any more there is hope Martin can implement some Metal based advancements in the next version.
Back to Falcon as it is now, with the old Sponza model, great fun anyways:
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Obviously a major reason for getting the 1070 was to take advantage of GPU acceleration (although my main reason was that my existing card was malfunctioning…), but so far my results are equivocal (not helped by Blender's rather strange way of labelling settings).
I'm not having much luck setting up the model nicely in Blender (with C3D importing the 3DS file got my all material assignments; all I needed to do was add a link in each material to do bump-mapping (and then a bit of extra work on one material to try to further improve the bump mapping for the stuff closest to the camera). Also, the latest version of Blender seems to have screwed up basic selection, which is driving me nuts.
That said, I got a half-assed scene set up and did some test renders. Looks like I can render 1920x1080 128spp in ~2mins using GPU and ~8mins using CPUs (it's an old Mac Pro so thats a 3.2GHz Xeon with 4 cores).
One thing I notice in both your and my Cycles renders is that the sun shadows are WAY too soft.
I'm not having much luck setting up the model nicely in Blender (with C3D importing the 3DS file got my all material assignments; all I needed to do was add a link in each material to do bump-mapping (and then a bit of extra work on one material to try to further improve the bump mapping for the stuff closest to the camera). Also, the latest version of Blender seems to have screwed up basic selection, which is driving me nuts.
That said, I got a half-assed scene set up and did some test renders. Looks like I can render 1920x1080 128spp in ~2mins using GPU and ~8mins using CPUs (it's an old Mac Pro so thats a 3.2GHz Xeon with 4 cores).
One thing I notice in both your and my Cycles renders is that the sun shadows are WAY too soft.
When you got problems with setting up the model in Blender, what about trying to get the working Cheetah model into Blender via fbx or obj+mtl?
The softness of the shadows in blender can be easily adjusted per area light dimensions.
(I've not tested that yet but that could mean longer render times because smaller lights are harder to find for the sampling algorithm.)
I'm confused about what the actual size of the thing is, when I look at the doors which are really small, it would be rather huge, and wider distances would make softer shadows.
Fourfold speed bump sounds great to me :smile:
I wish there was a readymade thunderbolt solution for MacBooks but from what I find on the web (Akitio a.o.) it's a hardware geek thing with power units needing replacement and stuff which i'm not really up to.
The softness of the shadows in blender can be easily adjusted per area light dimensions.
(I've not tested that yet but that could mean longer render times because smaller lights are harder to find for the sampling algorithm.)
I'm confused about what the actual size of the thing is, when I look at the doors which are really small, it would be rather huge, and wider distances would make softer shadows.
Fourfold speed bump sounds great to me :smile:
I wish there was a readymade thunderbolt solution for MacBooks but from what I find on the web (Akitio a.o.) it's a hardware geek thing with power units needing replacement and stuff which i'm not really up to.
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I'm just using the "sun" light in Blender. I'm sure the shadows in Blender are wrong there since I calculated the size of the area light in C3D and the resulting shadows also look right and are much harder.
I'm guessing that Blender's defaults at least are probably designed to please people wanting soft shadows (and avoid "soft shadows aren't working" bug reports) rather than produce correct results. (If Blender's defaults were, in general, calibrated for pleasing output that would be one thing, but the default renders in blender always look like shit to me, whereas I can drop a skylight into pretty much any C3D scene and get terrific results, aside from the hard shadows.)
I'm hoping that when Apple releases new Mac Pros they're mini-towers, but I'd be pretty happy with Thunderbolt + USB3 + USB-C in the old chassis OR just an official works-out-of-the-box thunderbolt PCI expansion bus that let me use a Macbook Pro or iMac and a bunch of insane bleeding edge shit.
The old Mac Pros were expensive, but they last forever and are easy to upgrade. (If I wanted to blow $2000 I could make this box as fast as anything out there, which is to say about 50% faster than it is right now for CPU-bound stuff, which would be hardly noticeable.)
I may try exporting my scene from C3D. The thing this scene really needs is displacement-mapping, because when you get even slightly close to the walls the edges look totally wrong.
Attached are two new renders.
I've tried a bit of hand-tweaking of the texture map, which had little benefit (the original is actually quite high resolution, it's just not very good). I also tried sourcing a replacement map without success (somewhere I have a box full of photos I took on vacation in Italy with a pretty decent camera… Ah analog.)
One concrete improvement I did make is to fix texture-mapping errors from the 3DS file on the square level 2 columns (you can see them on the left).
I'm guessing that Blender's defaults at least are probably designed to please people wanting soft shadows (and avoid "soft shadows aren't working" bug reports) rather than produce correct results. (If Blender's defaults were, in general, calibrated for pleasing output that would be one thing, but the default renders in blender always look like shit to me, whereas I can drop a skylight into pretty much any C3D scene and get terrific results, aside from the hard shadows.)
I'm hoping that when Apple releases new Mac Pros they're mini-towers, but I'd be pretty happy with Thunderbolt + USB3 + USB-C in the old chassis OR just an official works-out-of-the-box thunderbolt PCI expansion bus that let me use a Macbook Pro or iMac and a bunch of insane bleeding edge shit.
The old Mac Pros were expensive, but they last forever and are easy to upgrade. (If I wanted to blow $2000 I could make this box as fast as anything out there, which is to say about 50% faster than it is right now for CPU-bound stuff, which would be hardly noticeable.)
I may try exporting my scene from C3D. The thing this scene really needs is displacement-mapping, because when you get even slightly close to the walls the edges look totally wrong.
Attached are two new renders.
I've tried a bit of hand-tweaking of the texture map, which had little benefit (the original is actually quite high resolution, it's just not very good). I also tried sourcing a replacement map without success (somewhere I have a box full of photos I took on vacation in Italy with a pretty decent camera… Ah analog.)
One concrete improvement I did make is to fix texture-mapping errors from the 3DS file on the square level 2 columns (you can see them on the left).
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Looks great on my 3k screen, but also shows the limits of the model and the textures. There need to be better textures (not necessary resolution, but color depth and no jpeg artifacts) and also the hard edges of the geometry are disturbing. The pillars can be subdivided (3x linear + 2x subdiv) but the triangulated arches need to be beveled and that destroys the existing uv maps...
I had a go with procedural stones but those are a huge slowdown.
Testing with simpler setups showed that a simple fractal noise is already a bit slower than a noise image map, both diffuse or bump, and fancy node settings easily quadruple Falcon render times.
I had a go with procedural stones but those are a huge slowdown.
Testing with simpler setups showed that a simple fractal noise is already a bit slower than a noise image map, both diffuse or bump, and fancy node settings easily quadruple Falcon render times.
jdmac
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One HDRI light source
My first take using a single HDRI (no other lights).
Both Falcon renders use a variation of the same HDRI (preview attached).
Render 1 (bluish tint):
Render 2:
Now, one doesn't always want to render with a bright sunny day, but I'm glad to discover that it can be done using one HDRI.
As a side note, I think there is a similar "problem" with using the Sky Light in Cheetah. The Sky Light sun isn't strong enough compared to the sky itself. Increasing the Sky Light intensity brightens the sky along with the sun, and doesn't look natural. It actually looks more like over-exposing with a camera which doesn't provide a fuller dynamic range.
@Martin, what is the dynamic range of the Sky Light? Is that something that can be increased?
HDRI source: https://www.poliigon.com/texture/2229 (I have no affiliation)
My first take using a single HDRI (no other lights).
Both Falcon renders use a variation of the same HDRI (preview attached).
Render 1 (bluish tint):
- Original HDRI
- HDRI Intensity: 3.0
- Clamp: 250.0
- Exposure: 6.0
- Gamma 2.4
- Samples: 200
- Total bounces: 32
- Diffuse bounces: 24
- Glossy bounces: 4
- Specular bounces: 8
Render 2:
- Modified HDRI (added white circle 20+stops on top of sun)
- HDRI Intensity: 1.0
- Clamp: 750.0
- Exposure: 1.0
- Gamma 3.0
- Samples: 200
- Total bounces: 32
- Diffuse bounces: 24
- Glossy bounces: 4
- Specular bounces: 8
Now, one doesn't always want to render with a bright sunny day, but I'm glad to discover that it can be done using one HDRI.
As a side note, I think there is a similar "problem" with using the Sky Light in Cheetah. The Sky Light sun isn't strong enough compared to the sky itself. Increasing the Sky Light intensity brightens the sky along with the sun, and doesn't look natural. It actually looks more like over-exposing with a camera which doesn't provide a fuller dynamic range.
@Martin, what is the dynamic range of the Sky Light? Is that something that can be increased?
HDRI source: https://www.poliigon.com/texture/2229 (I have no affiliation)
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Looks great too,
but I can see that you use the original model which has quite some issues with overlapping triangle geometry that needs to be cleaned up first,
and also the textures don't work in some places but that's the case in every version I came across so far.
Is that a free HDRI?
but I can see that you use the original model which has quite some issues with overlapping triangle geometry that needs to be cleaned up first,
and also the textures don't work in some places but that's the case in every version I came across so far.
Is that a free HDRI?
jdmac
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Yes, I noticed that, but didn't bother fixing since I was mainly focused on testing the HDRI with +20stops bump on the sun.
The HDRI render looks very similar to the tests I ran using the spherical area light you suggested.
Yes, the HDRI is free download. They have quite a few free good textures, as well: https://www.poliigon.com/search/recent/narrow/list/free textures
Thanks for the link!