Interactive Indirect Illumination Using Voxel Cone Tracing: A Preview

Best poster awardInternational audiencePoster ACM SIGGRAPH Symposium on Interactive 3D Graphics and Games (I3D). Best poster awar

Remote and scalable interactive high-fidelity graphics using asynchronous computation

Current computing devices span a large and varied range of computational power. Interactive high-fidelity graphics is still unachievable on many of the devices widely available to the public, such as desktops and laptops without high-end dedicated graphics cards, tablets and mobile phones. In this paper we present a scalable solution for interactive high-fidelity graphics with global illumination in the cloud. Specifically, we introduce a novel method for the asynchronous remote computation of indirect lighting that is both scalable and efficient. A lightweight client implementation merges the remotely computed indirect contribution with locally computed direct lighting for a full global illumination solution. The approach proposed in this paper applies instant radiosity methods to a precomputed point cloud representation of the scene; an equivalent structure on the client side is updated on demand, and used to reconstruct the indirect contribution. This method can be deployed on platforms of varying computational power, from tablets to high-end desktops and video game consoles. Furthermore, the same dynamic GI solution computed on the cloud can be used concurrently with multiple clients sharing a virtual environment with minimal overheads.peer-reviewe

Стан та перспективи подальших досліджень сфери обчислення глобального освітлення у реальному часі

Currently, computer graphics is a very important part of computer science. Graphics-related developments have been used in many different situations, for example, in animated and cinema movie productions, in computer graphics applications, modeling, and simulation systems, for different visualizations in medicine, mathematics, physics, etc. One of the main problems of computer graphics is the task of transforming the information of some imaginary scene and its observer into a photorealistic image of this scene for them. Solving this problem is very important, but right now obtaining a good quality result is possible only in a non-interactive scenario (for example, in animated films), while in real-time (for example, in computer modeling or simulations, in computer games) it is usually necessary to use some approximate algorithms. Although these algorithms are often able to provide a natural-looking result, they still have plenty of very noticeable inaccuracies. However, this topic is gaining more and more development recently due to the improvement of graphics processors. In addition to a significant increase in computation speed and the number of cores, the appearance of ray tracing hardware acceleration plays a large role. Global illumination computation is an inseparable part of photorealistic image generation. This paper is focused on solving this problem in real-time, which means developing a system capable of generating such images at a speed sufficient for the resulting sequence to be perceived by a person as a smooth animation. We give the theoretical information required for understanding this problem and describe existing methods and algorithms for solving it with their advantages and disadvantages. Also based on an overview of the topic's current state, we analyze further research prospects and directions for improving existing and developing new methods of real-time global illumination calculation, while considering compute power and technologies of the latest graphics hardware. Pages of the article in the issue: 72 - 79 Language of the article: UkrainianУ статті розглядається така проблема сучасної комп’ютерної графіки як обчислення глобального освітлення в реальному часі. Глобальне освітлення є невід’ємною частиною фотореалістичного рендерінгу, але його підрахунок потребує доволі об’ємних обчислень. Через це на даний момент якісне глобальне освітлення існує лише у неінтерактивних рендерах (наприклад, у мультиплікаційних фільмах), а у реальному часі (наприклад, комп’ютерному моделюванні або симуляціях, комп’ютерних іграх) зазвичай використовуються певні наближення, які хоч і надають зображенню певну природність, але все одно мають вкрай помітні неточності. Але останнім часом дана тема набуває все більшого розвитку за рахунок удосконалення відеопроцессорів. Крім значного підвищення їх швидкодії та збільшення кількості ядер досить велику роль грає поява апаратного прискорення трасування променів. В даній роботі проводиться теоретичне дослідження проблеми глобального освітлення, наводяться існуючи підходи та розробки для вирішення даної проблеми та аналізуються перспективи подальших досліджень та розробки нових методів обчислення глобального освітлення в реальному часі з урахуванням новітніх апаратних можливостей обчислювальної техніки

An Overview of Modern Global Illumination

Advancements in graphical hardware call for innovative solutions, which can improve the realism of computer generated lighting. These innovative solutions aim to generate state of the art computer generated lighting through a combination of intelligent global illumination models and the use of modern hardware. The solution described in this paper achieves global illumination by ray tracing over geometry within a 3D scene from distributed light field probes and proceeds to shade the scene with a deferred renderer. Such a solution provides the flexibility and robustness that many other global illumination models have previously lacked while still achieving realistic lighting that is representative of the capabilities of the operating hardware

Photon Splatting Using a View-Sample Cluster Hierarchy

Splatting photons onto primary view samples, rather than gathering from a photon acceleration structure, can be a more efficient approach to evaluating the photon-density estimate in interactive applications, where the number of photons is often low compared to the number of view samples. Most photon splatting approaches struggle with large photon radii or high resolutions due to overdraw and insufficient culling. In this paper, we show how dynamic real-time diffuse interreflection can be achieved by using a full 3D acceleration structure built over the view samples and then splatting photons onto the view samples by traversing this data structure. Full dynamic lighting and scenes are possible by tracing and splatting photons, and rebuilding the acceleration structure every frame. We show that the number of view-sample/photon tests can be significantly reduced and suggest further culling techniques based on the normal cone of each node in the hierarchy. Finally, we present an approximate variant of our algorithm where photon traversal is stopped at a fixed level of our hierarchy, and the incoming radiance is accumulated per node and direction, rather than per view sample. This improves performance significantly with little visible degradation of quality

A general illumination model for molecular visualization

Several visual representations have been developed over the years to visualize molecular structures, and to enable a better understanding of their underlying chemical processes. Today, the most frequently used atom-based representations are the Space-filling, the Solvent Excluded Surface, the Balls-and-Sticks, and the Licorice models. While each of these representations has its individual benefits, when applied to large-scale models spatial arrangements can be difficult to interpret when employing current visualization techniques. In the past it has been shown that global illumination techniques improve the perception of molecular visualizations; unfortunately existing approaches are tailored towards a single visual representation. We propose a general illumination model for molecular visualization that is valid for different representations. With our illumination model, it becomes possible, for the first time, to achieve consistent illumination among all atom-based molecular representations. The proposed model can be further evaluated in real-time, as it employs an analytical solution to simulate diffuse light interactions between objects. To be able to derive such a solution for the rather complicated and diverse visual representations, we propose the use of regression analysis together with adapted parameter sampling strategies as well as shape parametrization guided sampling, which are applied to the geometric building blocks of the targeted visual representations. We will discuss the proposed sampling strategies, the derived illumination model, and demonstrate its capabilities when visualizing several dynamic molecules.Peer ReviewedPostprint (author's final draft