# Overview
This repository includes a number of example scenes and
data for use with the [pbrt-v3](https://github.com/mmp/pbrt-v3) renderer,
which corresponds to the system described in the third edition of
_Physically Based Rendering_, by Matt Pharr, Wenzel Jakob, and Greg
Humphreys. (See also the [pbrt website](http://pbrt.org).)
We hope that this data will be useful to users of `pbrt`, developers making
changes to the system, and researchers in rendering. To our knowledge, all
of these scenes and data can be used fairly freely. Some data is licensed
under a Creative Commons Attribution license; see details in
Section [Overview of Scenes] of this document.
For more information about how to convert scenes to `pbrt`'s format, see
the [pbrt User's
Guide](http://pbrt.org/users-guide.html#Converting_Scenes_to_pbrts_Format_0).
# Data Sets
In addition to example scenes, there is some useful data for use with the
system.
* [bsdfs/](bsdfs/): this directory includes a variety of bidirectional scattering
distribution functions (BSDFs) for use with the `FourierMaterial`. See, for
example, the [coffee-splash](coffee-splash) scene for use of such a BSDF in a scene.
* New versions of BSDFs for use with `FourierMaterial` can be generated
with [layerlab](https://github.com/wjakob/layerlab/).
* [lenses/](lenses/): lens description files for a handful of real-world lens
systems, for use with the `RealisticCamera`. See the scenes
[villa/villa-photons.pbrt](villa/villa-photons.pbrt) and
[sanmiguel/f6-17.pbrt](sanmiguel/f6-17.pbrt) for examples of their use.
* [spds/](spds/): measured spectral power distributions for a variety of standard
illuminants, light sources, metals, and the squares of the Macbeth color
checker.
# Scenes
A variety of scenes are available, ranging from simple ones that show off
an individual feature of the system, to more interesting ones that
demonstrate complex lighting effects in scenes with detailed geometry and
realistic reflection models.
Scene files for many of the rendered figures in the book are included here;
for example, [dragon/f11-13.pbrt](dragon/f11-13.pbrt) corresponds to Figure
11.13 in the third edition of the book.
## Directory Organization
We've tried to organize all of the scene directories in a consistent
manner; each scene directory is self-contained, containing all of the
geometry, textures, and additional data needed to render the scene.
With a few exceptions, each `*.pbrt` file in a scene directory represents a
separate variant of the scene to be rendered (possibly with different light
source configurations, different camera positions, etc.) Some scenes have
`geometry.pbrt`, `lights-*.pbrt` and `materials.pbrt` files that collect
common geometry and material definitions across these variants. Thus, you
should be able to just run `pbrt scene-name.pbrt` for any of the remaining
`*.pbrt` files to render the corresponding scene.
Complex triangle meshes and other complex geometry is stored in the
`geometry/` directories and texture maps are all in the respective
`textures/` directories. (Similarly, any SPDs, realistic camera lenses,
or BSDF files are stored in corresponding sub-directories.)
The [images/](images/) directory (which has a structure that parallels that
of the scene directories) has EXR and PNG files corresponding to the final
output from rendering each corresponding scene. All PNGs were generated
using the `imgtool` program from the `pbrt-v3` distribution; many had a
scale factor applied with the `--scale` command-line option, and a number
include a bit of bloom to improve visual realism (via the `--bloomlevel`
and related command-line options.) Sometimes the corresponding `*.pbrt`
file has a comment under the `Film` directive with the command line options
that were used for `imgtool`.
## A Note about Clamped Sample Values
Some of these scenes have very difficult-to-sample light transport paths
that in turn cause high variance, which manifests itself as scattered very
bright pixels in images (often called "fireflies"). (For example, scenes
with bumpy specular surfaces that are illuminated by realistic sky environment
maps suffer from this issue when a path intersects the specular surface and
is then scattered such that it happens to intersect the sun.)
There is an option for pbrt's Film implementation that allows the user to
specify a maximum value for the luminance of any sample added to the film;
if enabled, any sample with a larger luminance has its luminance scaled
down so that it is equal to the maximum. In turn, the impact of fireflies
in images can be greatly reduced.
We have used this option for a number of challenging scenes in the
following. As such, **bias has been introduced into the the images that
pbrt generates for those scenes**. We highlight this issue for two reasons:
first, if you want to use those scenes as unbiased comparisons to another
rendering system or to your implementation of a new light transport
algorithm, it's important to be aware of this (and likely, to modify the
scene files to disable this setting). Second, if you're developing a new
light transport algorithm, these scenes provide a number of challenging
situations that current algorithms don't handle well; new algorithms that
handle them effectively would be useful contributions to rendering.
## Overview of Scenes
(##) Barcelona Pavilion
![](images/barcelona-pavilion/pavilion-day.png height="200px")
![](images/barcelona-pavilion/pavilion-night.png height="200px")
[barcelona-pavilion](barcelona-pavilion): Model of van der Rohe's classic
[Barcelona Pavilion](https://en.wikipedia.org/wiki/Barcelona_Pavilion),
including both daytime and nighttime lighting setups. In the daytime setup,
all illumination comes from a realistic sky model encoded in an HDR
environment map. The night model has a very dark sky map and a number of
area light sources; it is particularly challenging to render, as much of
the illumination travels through one or more layers of glass before hitting
a surface.
barcelona-pavilion: Thanks to [Hamza Cheggour](http://www.emirage.org), who
created this [great
model](http://www.emirage.org/2013/04/24/free-download-archviz-project-pabellon-barcelona-3d-scene-v1-2-updated/)
and made it available via a
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license.
(##) Bathroom
![](images/bathroom/bathroom.png height="200px")
[bathroom](bathroom): Modern bathroom with soft indirect lighting and
depth of field. Given the mirrors and bright wight walls, multi-bounce
indirect illumination has a substantial effect on the overall appearance
of the scene.
Thanks to "nacimus", who made this scene available under the
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license. Downloaded
from [Blendswap](http://www.blendswap.com/blends/view/73937).
(##) BMW M6
![](images/bmw-m6/bmw-m6.png height="200px")
[bmw-m6](bmw-m6): BMW M6 car (model year 2006) illuminated by a realistic
skylight model.
Thanks to Fred C. M'ule Jr. ("tyrant monkey" on BlendSwap) for this nice
car model. [CC-Zero](https://creativecommons.org/publicdomain/zero/1.0/)
(public domain) license. Downloaded from
[Blendswap](http://www.blendswap.com/blends/view/3557).
(##) Breakfast
![](images/breakfast/breakfast-lamps.png height="200px")
[breakfast](breakfast): Indoor scene with chairs around a table. One
variant of the scene has light streaming in through blinds from the side
such that most of the scene is only illuminated indirectly; finding these
indirect illumination paths can be challenging. Another variant is only
illuminated by the lights above the table; handling the resulting light
transport through the glass light fixtures is a good challenge for many
light transport algorithms.
Thanks to "Wig42", who made this scene available under a
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license. Downloaded
from [Blendswap](http://www.blendswap.com/blends/view/75431).
(##) Buddha Fractal
![](images/buddha-fractal/buddha-fractal.png height="200px")
[buddha-fractal](buddha-fractal): Stanford Buddha model made out of Stanford Buddha
models. 25,250 instances, each with 29,890 triangles, giving a total
geometric complexity of over 750 million triangles.
Thanks for Guillermo M. Leal Llaguno for this fun variant
of the Stanford Buddha model. (Buddha model courtesy [Stanford Computer
Graphics Laboratory](http://graphics.stanford.edu/data/3Dscanrep/)).
(##) Bunny Fur
![](images/bunny-fur/f3-15.png height="200px")
[bunny-fur](bunny-fur): Stanford Bunny with fur growing out of it, modeled using the
new curve shape added to `pbrt` in the third edition of the book. Over
1.5 million curves are used.
Bunny model courtesy [Stanford Computer Graphics
Laboratory](http://graphics.stanford.edu/data/3Dscanrep/). Environment map
thanks to [Bernhard Vogl](http://dativ.at/lightprobes/index.html).
(##) Caustic Glass
![](images/caustic-glass/f16-9c.png height="200px")
[caustic-glass](caustic-glass): A delightfully complex caustic pattern that
results from light being projected through a realistic model of a bumpy
glass.
Thanks to Simon Wendsche (https://byob.carbonmade.com/) for
the model.
(##) Chopper Titan
![](images/chopper-titan/chopper-titan.png height="200px")
[chopper-titan](chopper-titan): Shiny motorcycle sitting on a glossy
surface, illuminated by a sunset.
Thanks to julioras3d for this model;
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license. Downloaded
from [Blendswap](http://www.blendswap.com/blends/view/67726).
(##) Cloud
![White cloud](images/cloud/cloud.png height="200px")
![Smoky cloud](images/cloud/smoke.png height="200px")
[cloud](cloud): One scene with a bright white cloud, showing the effect of
multiple scattering in participating media, and another, with the same
volume density but with much more absorption, leading to a much darker
cloud. The two images show the difference between highly-scattering and
highly-absorptive media.
Smoke dataset courtesy Duc Nguyen and Ron Fedkiw. Skylight
environment map courtesy Nolan Goodnight.
(##) Coffee Splash
![](images/coffee-splash/splash.png height="200px")
[coffee-splash](coffee-splash): A splash of coffee in a cup with a spoon,
rendered using a complex simulated BRDF for the cup and saucer, and
multiple scattering in participating media inside the splash.
Scene thanks to "guismo";
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license. Downloaded
from [Blendswap](http://www.blendswap.com/blends/view/56136). Environment
thanks to [Bernhard Vogl](http://dativ.at/lightprobes/index.html).
(##) Contemporary Bathroom
![](images/contemporary-bathroom/contemporary-bathroom.png height="200px")
[contemporary-bathroom](contemporary-bathroom): Another contemporary
bathroom scene. This scene is quite challenging to render without visible
noise: specular light transport by the large mirror and the
very small area light sources surrounded by glass in the light bulbs are
difficult to render efficiently.
Scene thanks to [Mareck](http://www.studios-cad.fr/galerie.html),
[CC-Zero](https://creativecommons.org/publicdomain/zero/1.0/) (public
domain) license. "contemporary_china" texture used for wallpaper thanks to
[Adam Charlts](http://subtlepatterns.com/contemporary-china/); texture
contrast was increased for the render. "American_walnut_pxr128" wood
texture courtesy [Pixar Animation
studios](https://community.renderman.pixar.com/article/114/library-pixar-one-twenty-eight.html),
[CC-BY](https://creativecommons.org/licenses/by/4.0/) license. Abstract
print seen in mirror based on a smoke photograph by [Vanessa
Pike-Russell](https://www.flickr.com/photos/lilcrabbygal/),
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license; the photo
was inverted and contrast was adjusted for rendering. Hurricane image used
for photo on wall courtesy [NASA Goddard Space Flight
Center](https://www.flickr.com/photos/gsfc),
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license.
(##) Crown
![](images/crown/crown.png height="200px")
[crown](crown): Detailed model of the Austrian Imperial Crown, featuring an
accurate reflection model for the gold metal surfaces, and many gems that
refract light passing through them.
This amazing model was created by Martin Lubich (http://www.loramel.net/).
(##) Dam Break
![](images/dambreak/dambreak0.png height="200px")
![](images/dambreak/dambreak1.png height="200px")
[dambreak](dambreak): two frames of a fluid simlulation from [Yining Karl
Li](http://www.yiningkarlli.com)'s nifty [Ariel fluid
simulator](http://www.yiningkarlli.com/projects/arielflip.html).
(##) Dragon
![](images/dragon/f9-3.png height="200px")
[dragon](dragon): A scanned dragon model rendered with many different materials,
showing off the visual differences between them.
Dragon model courtesy Christian Schüller. Environment map
thanks to [Bernhard Vogl](http://dativ.at/lightprobes/index.html).
(##) Ecosystem
![](images/ecosys/ecosys.png height="200px")
[ecosys](ecosys): Fairly complex outdoor scene with many plants and trees,
illuminated by an environment map. This scene was used for the cover image
for the first edition of _Physically Based Rendering_.
Scene from Deussen et al., [Realistic modeling and rendering of plant
ecosystems](http://dl.acm.org/citation.cfm?id=280898).
(##) Figures
[figures](figures): A variety of fairly simple scenes used for figures in the book.
(##) Ganesha
![](images/ganesha/ganesha.png height="200px")
[ganesha](ganesha): Very detailed scan of a small statue with over 4.3
million triangles, illuminated by a few area light sources.
Model scanned by Wenzel Jakob.
(##) Hair
![Curly hair](images/hair/curly-hair.png height="200px")
![Straight hair](images/hair/straight-hair.png height="200px")
[hair](hair): Hair geometry to show off the hair scattering model now
available in pbrt, as described in [The Implementation of a
Hair Scattering Model](http://pbrt.org/hair.pdf).
Many thanks to [Cem Yuskel](http://www.cemyuksel.com/) for the hair
geometry, which is licensed under a "no commercial use" license.
(##) Head
![](images/head/head.png height="200px")
[head](head): Human head model with a realistic BSSRDF, showing the effect of
subsurface scattering.
Model thanks to Infinite Realities, Inc.,
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license. Environment
map thanks to [USC-ICT light probe image
gallery](http://gl.ict.usc.edu/Data/HighResProbes/).
(##) Killeroo
![](images/killeroos/killeroo-gold.png height="200px")
[killeroos](killeroos): The classic "killeroo" model, in a variety of settings.
Thanks to [headus](http://www.headus.com/au)/Rezard for the model.
(##) Landscape
![](images/landscape/view-0.png height="200px")
![](images/landscape/view-1.png height="200px")
![](images/landscape/view-2.png height="200px")
![](images/landscape/view-3.png height="200px")
[landscape](landscape): Very complex realistic outdoor landscape scene,
featuring 23,241 unique plant models. Thanks to object instancing, the
scene has a total geometric complexity of 3.1 billion triangles, even
though only 24 million triangles need to be stored in memory. `view-0.pbrt`
is the cover image of the third edition of the _Physically Based Rendering_
book.
Many thanks to Jan-Walter Schliep, Burak Kahraman, and Timm
Dapper from [Laubwerk](http://www.laubwerk.com) for this amazing scene.
(##) LTE Orb
![Rough glass around gold](images/lte-orb/lte-orb-roughglass.png height="200px")
![Silver around diffuse](images/lte-orb/lte-orb-silver.png height="200px")
[lte-orb](lte-orb): Spherical orb with an inset spherical object. The
geometric structure of the shapes involved provides a useful tool for
visualizing the appearance of various materials.
Thanks to Yasutoshi Mori (@MirageYM) for this model;
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license.
(##) Measure One
![](images/measure-one/frame25.png height="200px")
![](images/measure-one/frame380.png height="200px")
[measure-one](measure-one): A number of frames converted from Beeple's
amazing [Zero-Day](https://vimeo.com/140163198) animation. Converted from
Cinema4D files downloaded from [Beeple's
website](http://www.beeple-crap.com/resources.php). (Note that the original
materials and lighting is much better--improvements to our conversion
gratefully received!)
[License]((http://beeple-crap.com/resources.php):
"These files are available under a sort of "open source" concept. They are
intended for educational use but really can be used for whatever the fuck
you want. You don't need to credit me for whatever commercial or
non-commercial use you make of them, but if you could shout me a holla with
any project that do come from them, I'd love to see it :)"
(##) PBRT Book
![](images/pbrt-book/book.png height="200px")
[pbrt-book](pbrt-book): A realistic model of the second edition of the _Physically
Based Rendering_ book.
Thanks to Karl Li (@yiningkarlli) for this fun model.
(##) San Miguel
![](images/sanmiguel/sanmiguel.png height="200px")
[sanmiguel](sanmiguel): A complex model inspired by a hotel in San Miguel de
Allende, Mexico.
Thanks to Guillermo M. Leal Llaguno for this excellent scene.
(##) Simple
![](images/simple/anim-bluespheres.png height="200px")
[simple](simple): A variety of relatively simple scenes.
(##) Smoke Plume
![](images/smoke-plume/plume-084.png height="200px")
![](images/smoke-plume/plume-184.png height="200px")
![](images/smoke-plume/plume-284.png height="200px")
A few renderings of a smoke simulation around an obstacle using volume data
generated using the simulator published with Kim et al.'s [Wavelet
Turbulence for Fluid Simulation](https://www.cs.cornell.edu/~tedkim/wturb/)
paper.
(##) Sportscar
![](images/sportscar/sportscar.png height="200px")
[sportscar](sportscar): Sportscar model, in a variety of illumination settings,
showing off the substantial differences in overall visual appearance that
result.
Excellent model and pbrt conversion courtesy of Yasutoshi Mori (@MirageYM);
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license. Skylight
environment maps courtesy Nolan Goodnight.
(##) SSS Dragon
![](images/sssdragon/dragon_10.png height="200px")
[sssdragon](sssdragon): Dragon model rendered with subsurface scattering,
where multiple scene description files show the visual effect of changing
the density of the scattering medium.
Dragon model courtesy [Stanford Computer Graphics
Laboratory](http://graphics.stanford.edu/data/3Dscanrep/). Environment map
thanks to [Bernhard Vogl](http://dativ.at/lightprobes/index.html).
(##) StructureSynth
![](images/structuresynth/arcsphere.png height="200px")
[structuresynth](structuresynth): A few interesting procedural scenes scenes converted
from [Structure Synth](http://structuresynth.sourceforge.net) into
`pbrt`'s format.
Environment map thanks to [USC-ICT light probe image
gallery](http://gl.ict.usc.edu/Data/HighResProbes/).
(##) Transparent Machines
![](images/transparent-machines/frame888.png height="200px")
![](images/transparent-machines/frame542.png height="200px")
[transparent-machines](transparent-machines): A variety of highly detailed
glass shapes illuminated by skylight. For good results, upwards of 64 ray
bounces are required.
Models from frames of [@beeple](http://beeple-crap.com)'s amazing
[Transparent Machines
video](https://vimeo.com/78716671). [License]((http://beeple-crap.com/resources.php):
"These files are available under a sort of "open source" concept. They are
intended for educational use but really can be used for whatever the fuck
you want. You don't need to credit me for whatever commercial or
non-commercial use you make of them, but if you could shout me a holla with
any project that do come from them, I'd love to see it :)"
(##) TT Car
![](images/tt/tt.png height="200px")
[tt](tt): Audi TT car model.
Thanks for Marko Dabrovic and Mihovil Odak for the car model. Environment
map thanks to [USC-ICT light probe image
gallery](http://gl.ict.usc.edu/Data/HighResProbes/).
(##) Veach Bidir
![](images/veach-bidir/bidir.png height="200px")
[veach-bidir](veach-bidir): A version of a classic scene with a variety of complex
types of light transport developed by Eric Veach to show the value of
bidirectional path tracing.
(##) Veach MIS
![](images/veach-mis/f14-13-mi.png height="200px")
[veach-mis](veach-mis): Another scene based on one by Eric Veach, this one showing
off the benefit of multiple importance sampling when rendering surfaces
of varying glossiness illuminated by light sources of various sizes.
(##) Villa
![](images/villa/villa-daylight.png height="200px")
[villa](villa): Modern indoor environment. The `villa-daylight.pbrt` version is
particularly tricky to render, as all of the indoor lighting comes via
specular paths from the outside through the windows.
Many thanks to Florent Boyer for this scene. Skylight environment
map courtesy Nolan Goodnight.
(##) VW Van
![](images/vw-van/vw-van.png height="200px")
[vw-van](vw-van): Volkswagen Van, illuminated by a HDR environment map.
Model courtesy of
[Greyscalegorilla](https://greyscalegorilla.com/gsg-free-model-pack-for-cinema-4d/),
exported from Cinema4D using the [Cinema4D pbrt
exporter](https://github.com/mmp/pbrt-v3/tree/master/exporters/cinema4d).
(##) Volume Caustic
![](images/volume-caustic/caustic.png height="200px")
[volume-caustic](volume-caustic): A glass sphere in participating media, showing off a
volumetric caustic--light being focused in the scattering medium after
passing through the sphere.
(##) White Room
![](images/white-room/whiteroom-daytime.png height="200px")
![](images/white-room/whiteroom-night.png height="200px")
[white-room](white-room): Interior scene, with two illumination
configurations. The daytime variant is primarily illuminated by light
coming through the windows from the outdoors, while the nighttime version
is illuminated by the two lights in the scene.
Scene thanks to Jay Hardy,
[CC-BY](https://creativecommons.org/licenses/by/2.0/) license. Downloaded
from [Blendswap](http://www.blendswap.com/blends/view/41683).
(##) Yeah Right
![](images/yeahright/yeahright.png height="200px")
[yeahright](yeahright): An unusual and intricate form on a glossy plate.
"Interesting" shape generated by [Keenan
Crane](http://www.cs.cmu.edu/~kmcrane/Projects/ModelRepository/).
Environment map thanks to [USC-ICT light probe image
gallery](http://gl.ict.usc.edu/Data/HighResProbes/).
(##) WIP
[wip](wip): This directory has a few scenes that aren't quite ready;
renderings don't yet look great, parameters need tuning, etc. We'll try
to get to this eventually, or if you're able to get them in good shape,
please submit an update (see the following).