Module core

All the code for the PBRT core.

Modules

api

The parser reads a scene description more or less line by line and stores the read information by calling API functions starting with pbrt_.

bssrdf

The bidirectional scattering surface reflectance distribution function (BSSRDF) gives exitant radiance at a point on a surface given incident differential irradiance at another point.

camera

The abstract Camera base class holds generic camera options and defines the interface that all camera implementations must provide.

efloat

In addition to working out the error bounds algebraically, we can also have the computer do this work for us as some computation is being performed. This approach is known as running error analysis.

film

The type of film or sensor in a camera has a dramatic effect on the way that incident light is transformed into colors in an image. In pbrt, the Film class models the sensing device in the simulated camera. After the radiance is found for each camera ray, the Film implementation determines the sample’s contribution to the pixel around the point on the film plane where the camera ray began and updates its representation of the image. When the main rendering loop exits, the Film writes the final image to file.

filter

All filter implementations are derived from an abstract Filter class, which provides the interface for the functions used in filtering.

floatfile

Read text files that store a series of floating-point values.

geometry

Almost all nontrivial graphics programs are built on a foundation of geometric classes. These classes represent mathematical constructs like points, vectors, and rays.

integrator

Rendering an image of the scene is handled by an instance of a class that implements the Integrator interface.

interaction

The geometry of a particular point on a surface is represented by a SurfaceInteraction. Having this abstraction lets most of the system work with points on surfaces without needing to consider the particular type of geometric shape the points lie on; the SurfaceInteraction abstraction supplies enough information about the surface point to allow the shading and geometric operations in the rest of pbrt to be implemented generically.

interpolation

Spline-based interpolation to reconstruct BSDF values (instead of using large lookup tables).

light

In order for objects in a scene to be visible, there must be a source of illumination so that some light is reflected from them to the camera sensor.

lightdistrib

Various probability distributions for sampling light sources.

lowdiscrepancy

Algorithms that deal with low-discrepancy point sets.

material

The abstract Material class defines the interface that material implementations must provide.

medium

A key operation that Medium implementations must perform is to compute the beam transmittance along a given ray.

memory

Structs and utility routines related to memory management.

microfacet

Reflection models based on microfacets that exhibit perfect specular reflection and transmission have been effective at modeling light scattering from a variety of glossy materials, including metals, plastic, and frosted glass.

mipmap

To limit the potential number of texels that need to be accessed, filtering methods use an image pyramid of increasingly lower resolution prefiltered versions of the original image to accelerate their operation.

parallel

Using atomic operations on floating-point values. One example is splatting pixel contributions.

paramset

Bundle up parameters and their values in a generic way.

pbrt

Type definitions of Float and Spectrum, otherwise constants and functions which can be used almost everywhere else in the code.

primitive

The abstract Primitive base class is the bridge between the geometry processing and shading subsystems of pbrt.

quaternion

Quaternions were originally invented by Sir William Rowan Hamilton in 1843 as a generalization of complex numbers. He determined that just as in two dimensions, where complex numbers could be defined as a sum of a real and an imaginary part, a generalization could be made to four dimensions, giving quaternions.

reflection

When light is incident on the surface, the surface scatters the light, reflecting some of it back into the environment. There are two main effects that need to be described to model this reflection: the spectral distribution of the reflected light and its directional distribution.

rng

Random Number Generator

sampler

The Sampler base class not only defines the interface to samplers but also provides some common functionality for use by Sampler implementations.

sampling

Draw random samples from a chosen probability distribution.

scene

As the scene file is parsed, objects are created that represent the lights and geometric primitives in the scene. These are all stored in the Scene object.

shape

Careful abstraction of geometric shapes in a ray tracer is a key component of a clean system design, and shapes are the ideal candidate for an object-oriented approach. All geometric primitives implement a common interface, and the rest of the renderer can use this interface without needing any details about the underlying shape. This makes it possible to separate the geometric and the shading subsystem of pbrt.

sobolmatrices

Matrices used by the SobolSampler.

spectrum

The Spectrum type hides the details of the particular spectral representation used, so that changing this detail of the system only requires changing the Spectrum implementation.

texture

Texture is a template class parameterized by return type of its evaluation function. This design makes it possible to reuse almost all of the code among textures that return different types. PBRT currently uses only Float and Spectrum textures.

transform

In general, transformations make it possible to work in the most convenient coordinate space.