A metadata-enhanced framework for high performance visual effects

This thesis is devoted to reducing the interactive latency of image processing computations in visual effects. Film and television graphic artists depend upon low-latency feedback to receive a visual response to changes in effect parameters. We tackle latency with a domain-specific optimising compiler which leverages high-level program metadata to guide key computational and memory hierarchy optimisations. This metadata encodes static and dynamic information about data dependence and patterns of memory access in the algorithms constituting a visual effect – features that are typically difficult to extract through program analysis – and presents it to the compiler in an explicit form. By using domain-specific information as a substitute for program analysis, our compiler is able to target a set of complex source-level optimisations that a vendor compiler does not attempt, before passing the optimised source to the vendor compiler for lower-level optimisation. Three key metadata-supported optimisations are presented. The first is an adaptation of space and schedule optimisation – based upon well-known compositions of the loop fusion and array contraction transformations – to the dynamic working sets and schedules of a runtimeparameterised visual effect. This adaptation sidesteps the costly solution of runtime code generation by specialising static parameters in an offline process and exploiting dynamic metadata to adapt the schedule and contracted working sets at runtime to user-tunable parameters. The second optimisation comprises a set of transformations to generate SIMD ISA-augmented source code. Our approach differs from autovectorisation by using static metadata to identify parallelism, in place of data dependence analysis, and runtime metadata to tune the data layout to user-tunable parameters for optimal aligned memory access. The third optimisation comprises a related set of transformations to generate code for SIMT architectures, such as GPUs. Static dependence metadata is exploited to guide large-scale parallelisation for tens of thousands of in-flight threads. Optimal use of the alignment-sensitive, explicitly managed memory hierarchy is achieved by identifying inter-thread and intra-core data sharing opportunities in memory access metadata. A detailed performance analysis of these optimisations is presented for two industrially developed visual effects. In our evaluation we demonstrate up to 8.1x speed-ups on Intel and AMD multicore CPUs and up to 6.6x speed-ups on NVIDIA GPUs over our best hand-written implementations of these two effects. Programmability is enhanced by automating the generation of SIMD and SIMT implementations from a single programmer-managed scalar representation

A Materials Science Driven Pattern Generation Solution to Fracturing Computer Generated Glass for Films and Games

Believably and realistically fracturing computer generated glass for visual effects has been previously solved through various methods such as algorithmic approaches, utilizing texture maps, or finite element analysis. These solutions can achieve some believable results but often at the cost of one or more of the following: simulation time, preparation time, art directability, consistency with materials science research, or the requirement of creating or utilizing fixed assets or maps. In this thesis I present a novel method that draws from the appropriate literature and focuses on quickly generating accurate fracture patterns. The method takes inputs such as the artist’s animation of an impact and desired object properties, and outputs fracture patterns used for breaking objects apart based on input values, materials science literature, and fracture mechanics. After determining all of the fracture pattern variables such as the number of radial and concentric cracks, the artist is able to override the computed parameters to retain control and art directability. Implementation of this method was performed using MAXScript, the built-in scripting language for Autodesk 3ds Max. The result is a computationally fast and mechanically accurate tool while retaining art directability to fulfill film storyboards or game design

On the Interoperability of Programming Languages based on the Fork-Join Parallelism Model

This thesis describes the implementation of MetaFork, a meta-language for concurrency platforms targeting multicore architectures. First of all, MetaFork is a multithreaded language based on the fork-join model of concurrency: it allows the programmer to express parallel algorithms assuming that tasks are dynamically scheduled at run-time. While MetaFork makes no assumption about the run-time system, it formally defines the serial C-elision of a MetaFork program. In addition, MetaFork is a suite of source-to-source compilers permitting the automatic translation of multithreaded programs between programming languages based on the fork-join model. Currently, this compilation framework supports the OpenMP and CilkPlus concurrency platforms. The implementation of those compilers explicitly manages parallelism according to the directives specified in MetaFork, OpenMP and CilkPlus. We evaluate experimentally the benefits of MetaFork. First, we show that this framework can be used to perform comparative implementation of a given multi- threaded algorithm so as to narrow performance bottlenecks in one implementation of this algorithm. Secondly, we show that the translation of hand written and highly optimized code within MetaFork generally produces code with similar performance as the original

A 3D Pipeline for 2D Pixel Art Animation

Aquest document presenta un informe exhaustiu sobre un projecte destinat a desenvolupar un procés automatitzat per a la creació d'animacions 2D a partir de models 3D utilitzant Blender. L'objectiu principal del projecte és millorar les tècniques existents i reduir la necessitat que els artistes realitzin tasques repetitives en el procés de producció d'animació. El projecte implica el disseny i desenvolupament d'un complement per a Blender, programat en Python, que es va desenvolupar per ser eficient i reduir les tasques intensives en temps que solen caracteritzar algunes etapes en el procés d'animació. El complement suporta tres estils específics d'animació: l'art de píxel, "cel shader", i "cel shader" amb contorns, i es pot expandir per suportar una àmplia gamma d'estils. El complement també és de codi obert, permetent una major col·laboració i potencials contribucions per part de la comunitat. Malgrat els problemes trobats, el projecte ha estat exitós en aconseguir els seus objectius, i els resultats mostren que el complement pot aconseguir resultats similars als adquirits amb eines similars i animació tradicional. El treball futur inclou mantenir el complement actualitzat amb les últimes versions de Blender, publicar-lo a GitHub i mercats de complements de Blender, així com afegir nous estils d'art.This document presents a comprehensive report on a project aimed at developing an automated process for creating 2D animations from 3D models using Blender. The project's main goal is to improve upon existing techniques and reduce the need for artists to do clerical tasks in the animation production process. The project involves the design and development of a plugin for Blender, coded in Python, which was developed to be efficient and reduce time-intensive tasks that usually characterise some stages in the animation process. The plugin supports three specific styles of animation: pixel art, cel shading, and cel shading with outlines, and can be expanded to support a wider range of styles. The plugin is also open-source, allowing for greater collaboration and potential contributions from the community. Despite the challenges faced, the project was successful in achieving its goals, and the results show that the plugin could achieve results similar to those acquired with similar tools and traditional animation. The future work includes keeping the plugin up-to-date with the latest versions of Blender, publishing it on GitHub and Blender plugin markets, as well as adding new art styles

Bronx Community College Catalog 2016-2016

Course catalog for Bronx Community College for 2015-16

Interactive freeform editing techniques for large-scale, multiresolution level set models

Level set methods provide a volumetric implicit surface representation with automatic smooth blending properties and no self-intersections. They can handle arbitrary topology changes easily, and the volumetric implicit representation does not require the surface to be re-adjusted after extreme deformations. Even though they have found some use in movie productions and some medical applications, level set models are not highly utilized in either special effects industry or medical science. Lack of interactive modeling tools makes working with level set models difficult for people in these application areas.This dissertation describes techniques and algorithms for interactive freeform editing of large-scale, multiresolution level set models. Algorithms are developed to map intuitive user interactions into level set speed functions producing specific, desired surface movements. Data structures for efficient representation of very high resolution volume datasets and associated algorithms for rapid access and processing of the information within the data structures are explained. A hierarchical, multiresolution representation of level set models that allows for rapid decomposition and reconstruction of the complete full-resolution model is created for an editing framework that allows level-of-detail editing. We have developed a framework that identifies surface details prior to editing and introduces them back afterwards. Combining these two features provides a detail-preserving level set editing capability that may be used for multi-resolution modeling and texture transfer. Given the complex data structures that are required to represent large-scale, multiresolution level set models and the compute-intensive numerical methods to evaluate them, optimization techniques and algorithms have been developed to evaluate and display the dynamic isosurface embedded in the volumetric data.Ph.D., Computer Science -- Drexel University, 201