Disney Enterprises, Inc.

Pixar

Eidgenossische Technische Hochschule Zurich

Disney Enterprise, Inc.

Wojciech Jarosz

Derek Nowrouzezahrai

Marios Papas

Wojciech Matusik

Jan Novak

Ralf Habel

Robert Walker Sumner

Kenneth John Mitchell

Ilya Baran

Kenny Mitchell

Peter-Pike Sloan

Szymon Marek Rusinkiewicz

Tim A Weyrich

Christian Regg

Steve Marschner

Wenzel A Jakob

Robert Thomas

Matthias Zwicker

Scott Frazier Watson

Markus H Gross

Philip John Jackson

Bernd Bickel

Andrew Selle

Manuel Lang

Huw David Bowles

Wenzel Jakob

Iliyan Georgiev

Michael Kaschalk

Peter Kutz

Toshiya Hachisuka

Jaroslav Kr̆ivánek

Frédo Durand

Stefan C Geiger

Thomas Williams

Thomas Houit

David Koerner

Benedikt Bitterli

Kartic Subr

Johannes Meng

Carsten Dachsbacher

Jared Johnson

Jesse Dylan Lacewell

Andy Selle

Jiawen Chen

Techniques are described for designing and manufacturing a surface that produces a desired image when illuminated by a light source. As described, the desired image may be decomposed into a collection of Gaussian kernels (referred to as Gaussians). A shape of a micropatch lens corresponding to each Gaussian may be determined, and the resulting micropatch lenses may be assembled to form a highly continuous surface that will cast an approximation of the desired image formed form the sum of a plurality of Gaussian caustics. The disclosed techniques may be used to create a design for a light-redirecting surface amenable to milling (or other manufacturing process).

Reflective and refractive surfaces configured to project desired caustic pattern

A method for creating a replication material corresponding to the appearance of a translucent or partially translucent target material. The appearance of the target material can be measured or may be prescribed by a user. The method includes receiving by a processor optical data related to a target subsurface scattering parameter of the target material. Once the processor has received the optical or light characteristic data, the method includes determining by the processor a replication pigment concentration to replicate the appearance of the target material caused by the target subsurface scattering parameter. The processor determines this concentration based on a plurality of pigment subsurface scattering parameters corresponding to a plurality of stored pigment concentrations in the computing device. Once the replication pigment concentration has been determined, the method includes creating, physically or virtually, the replication material by combining the pigment concentration with a base material.

Method of fabricating translucent materials with desired appearance

According to one exemplary implementation, a method for use by a global illumination system including a hardware processor includes identifying, using the hardware processor, a first interior vertex of multiple first interior vertices of a light path, the first interior vertices being situated within a volume having a refractive boundary. In addition, the method includes determining, using the hardware processor, a surface vertex of the light path at the refractive boundary, and determining, using the hardware processor, a linear direction from the surface vertex to a light source of the light path. The method also includes determining, using the hardware processor, one or more second interior vertices for completing the light path by constructing a path from the surface vertex to the first interior vertex, based on the linear direction, the surface vertex and the first interior vertex.

Ray tracing across refractive boundaries

Techniques for illuminating an indoor scene. A directional distribution associated with the indoor scene is received. The indoor scene has a first scene element and a first quadrilateral. The first scene element has a first shading point disposed thereon. The directional distribution is reparametrized such that the first quadrilateral as viewed from the first shading point corresponds to an axis-aligned rectangular region in the reparametrized directional distribution. The scene element is illuminated using one or more samples drawn from the shading point by performing importance sampling based on the reparametrized directional distribution.

Indoor scene illumination

There is provided a system including a memory storing a software application and a processor configured to execute the software application to transmit a light through a scene, the scene including a medium described by an extinction function, define a fictitious medium described by a fictitious extinction function, determine a path through the medium, the path including a plurality of points, calculate one of a plurality of weights for each of the plurality of points, the one of the plurality of weights corresponding to one minus the ratio of the extinction function to the fictitious extinction function, and estimate a transmittance of the lights through the medium as a product of the plurality of weights.

Residual ratio tracking for estimating attenuation in heterogeneous volumes

Systems, methods and articles of manufacture for sampling visual characteristics of a three-dimensional scene. Embodiments include collecting a plurality of samples within the three-dimensional scene. Upon determining that a combined stratified importance sampling algorithm will result in reduced error for a rendered image of the three-dimensional scene, embodiments collect the plurality of samples using the combined stratified importance sampling algorithm, and otherwise the plurality of samples are collected using a stratified sampling algorithm. The combined stratified importance sampling algorithm integrates an antithetic sampling algorithm. One or more lighting effects for the three-dimensional scene are simulated based on the plurality of samples and data describing one or more light sources for the three-dimensional scene. Embodiments further include rendering the image based on the simulated one or more lighting effects and data describing characteristics of the three-dimensional scene.

Combining sampling arrangements and distributions for stochastic integration in rendering

Methods and systems of joint path importance sampling are provided to construct light paths in participating media. The product of anisotropic phase functions and geometric terms across a sequence of path vertices are considered. A connection subpath is determined to join a light source subpath with a light receiver subpath with multiple intermediate vertices while considering the product of phase functions and geometry terms. A joint probability density function ('PDF') may be factorized unidirectional or bidirectional. The joint PDF may be factorized into a product of multiple conditional PDFs, each of which corresponds to a sampling routine. Analytic importance sampling may be performed for isotropic scattering, whereas tabulated importance sampling may be performed for anisotropic scattering.

Methods and systems of joint path importance sampling

The disclosure provides an approach for determining, in 3D rendering, the integrals of visibility-masked spherical functions using visibility silhouettes. For a given shade point, the visibility silhouette for that shade point includes a set of edges from the scene geometry which form the boundaries between visible and invisible regions of a hemisphere having the shade point as its center. For each shade point, a rendering application determines a set of contour edges of scene geometry, the contour edges being a superset of the set of visibility silhouette edges, by querying a 4D dual mesh. The rendering application then evaluates the integral of the visibility-masked spherical function for a given shade point by integrating over segments of discrete u-isolines for which an overlap function indicates that a ray from the shade point would not intersect scene geometry.

Visibility silhouettes for masked spherical integration

The disclosure provides an approach for rendering granular media. According to one aspect of the disclosure, granular media are rendered using bidirectional point scattering distribution functions (BPSDFs). The dimensionality of BPSDFs may be reduced by making certain assumptions, such as random orientations of grains, thereby simplifying light transport for computational efficiency. To generate a BPSDF from a grain, light transport may be precomputed using a Monte Carlo simulation in which photons are shot onto the grain from all directions. The precomputed BPSDF may be used, during rendering, for describing the interactions within grains. When a light ray traced during rendering intersects proxy geometry which replaces grain geometry, the BPSDF may be evaluated to determine light transport. By repeating this process for many light rays in a Monte Carlo simulation, the light propagation through the granular medium may be determined.

Bidirectional point distribution functions for rendering granular media

An efficient numerical method for accurately rendering translucent materials using photon beam diffusion is provided that can account for multilayer materials and directional incident and exitant effects at the surface. In an embodiment, refracted incident light is represented continuously as a photon beam instead of as discrete photons. An integration scheme for calculating a radiant exitance value at a point on the surface of the translucent material is disclosed that uses importance sampling and evaluates a radiant function at a limited number of points along the beam.

Photon beam diffusion

A method for creating artistic effects for volumetric illumination in a scene is provided. Data representing a scene is received. User input is received, which specifies a target appearance of the scene, including illumination effects that are at least in part non-physically-based. Photon beams representing volumetric illumination in the scene are generated; this step may incorporate user input-based modifications of the photon beams. Shading associated with the photon beams is computed; this step may also incorporate user input-based modifications. Any modifications in the generating or computing steps are derived from the specified target appearance of the scene. Finally, the photon beams are rendered.

Programmable system for artistic volumetric lighting

Rendering a scene with participating media is done by generating a depth map from a camera viewpoint and a shadow map from a light source, converting the shadow map using epipolar rectification to form a rectified shadow map (or generating the rectified shadow map directly), generating an approximation to visibility terms in a scattering integral, then computing a 1D min-max mipmap or other acceleration data structure for rectified shadow map rows and traversing that mipmap/data structure to find lit segments to accumulate values for the scattering integral for specific camera rays, and generating rendered pixel values that take into account accumulated values for the scattering integral for the camera rays. The scattering near an epipole of the rectified shadow map might be done using brute force ray marching when the epipole is on or near the screen. The process can be implemented using a GPU for parallel operations.

Rendering images with volumetric shadows using rectified height maps for independence in processing camera rays

A method for rendering radiance for a volumetric medium is provided. A photon simulation produces a representation of photon beams in a scene. The photon beams are rendered with respect to a camera viewpoint, by computing an estimated radiance associated with the photon beams. A global radius scaling factor can be applied to obtain different radii for the photon beams. Over multiple applications of these steps, the global radius scaling factor can be decreased, thereby reducing overall error by facilitating convergence. Finally, the renderer can be efficiently implemented on the GPU as a splatting operation, for use in interactive and real-time applications.

Image processing using progressive generation of intermediate images using photon beams of varying parameters

Techniques for displaying content using an augmented reality device are described. Embodiments provide a visual scene for display, the visual scene captured using one or more camera devices of the augmented reality device. Embodiments adjust physical display geometry characteristics of the visual scene to correct for optimal projection. Additionally, illumination characteristics of the visual scene are modified based on environmental illumination data to improve realism of the visual scene when it is displayed. Embodiments further adjust display characteristics of the visual scene to improve tone mapping output. The adjusted visual scene is then output for display on the augmented reality device.

Virtual lens-rendering for augmented reality lens

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Zurich, Switzerland

Wojciech Jarosz