Real-time illumination and shadowing by virtual lights in a mixed real-ity setting (original) (raw)

Achieving Interactive-Time Realistic Illumination in Mixed Reality

2004

Properly lighting virtual objects and having them cast shadows on each other based on dynamic lighting conditions is a computationally hard challenging Even more complex are the issues raised when this must be done in a Mixed Reality environment where virtual objects and virtual light interact with real objects and real light. This paper presents several interactive-time algorithms to enable interaction between real and virtual objects, including color matching, lighting and shadowing techniques.

AR360: Dynamic Illumination for Augmented Reality with Real-Time Interaction

2019 IEEE 2nd International Conference on Information and Computer Technologies (ICICT), 2019

Current augmented and mixed reality systems suffer a lack of correct illumination modeling where the virtual objects render the same lighting condition as the real environment. While we are experiencing astonishing results from the entertainment industry in multiple media forms, the procedure is mostly accomplished offline. The illumination information extracted from the physical scene is used to interactively render the virtual objects which results in a more realistic output in real-time. In this paper, we present a method that detects the physical illumination with dynamic scene, then uses the extracted illumination to render the virtual objects added to the scene. The method has three steps that are assumed to be working concurrently in real-time. The first is the estimation of the direct illumination (incident light) from the physical scene using computer vision techniques through a 360° live-feed camera connected to AR device. The second is the simulation of indirect illumination (reflected light) from the real-world surfaces to virtual objects rendering using region capture of 2D texture from the AR camera view. The third is defining the virtual objects with proper lighting and shadowing characteristics using shader language through multiple passes. Finally, we tested our work with multiple lighting conditions to evaluate the accuracy of results based on the shadow falling from the virtual objects which should be consistent with the shadow falling from the real objects with a reduced performance cost.

Interactive virtual relighting of real scenes

IEEE Transactions on Visualization and Computer Graphics, 2000

Computer augmented reality (CAR) is a rapidly emerging field which enables users to mix real and virtual worlds. Our goal is to provide interactive tools to perform common illumination, i.e., light interactions between real and virtual objects, including shadows and relighting (real and virtual light source modification). In particular, we concentrate on virtually modifying real light source intensities and inserting virtual lights and objects into a real scene; such changes can be very useful for virtual lighting design and prototyping. To achieve this, we present a three-step method. We first reconstruct a simplified representation of real scene geometry using semi-automatic vision-based techniques. With the simplified geometry, and by adapting recent hierarchical radiosity algorithms, we construct an approximation of real scene light exchanges. We next perform a preprocessing step, based on the radiosity system, to create unoccluded illumination textures. These replace the original scene textures which contained real light effects such as shadows from real lights. This texture is then modulated by a ratio of the radiosity (which can be changed) over a display factor which corresponds to the radiosity for which occlusion has been ignored. Since our goal is to achieve a convincing relighting effect, rather than an accurate solution, we present a heuristic correction process which results in visually plausible renderings. Finally, we perform an interactive process to compute new illumination with modified real and virtual light intensities. Our results show that we are able to virtually relight real scenes interactively, including modifications and additions of virtual light sources and objects.

An Empirical Evaluation of the Performance of Real-Time Illumination Approaches: Realistic Scenes in Augmented Reality

2019

Augmented, Virtual, and Mixed Reality (AR/VR/MR) systems have been developed in general, with many of these applications having accomplished significant results, rendering a virtual object in the appropriate illumination model of the real environment is still under investigation. The entertainment industry has presented an astounding outcome in several media form, albeit the rendering process has mostly been done offline. The physical scene contains the illumination information which can be sampled and then used to render the virtual objects in real-time for realistic scene. In this paper, we evaluate the accuracy of our previous and current developed systems that provide real-time dynamic illumination for coherent interactive augmented reality based on the virtual object’s appearance in association with the real world and related criteria. The system achieves that through three simultaneous aspects. (1) The first is to estimate the incident light angle in the real environment using...

Interactive image based lighting in augmented reality

Our work focuses on using Image Based Lighting in Aug-mented Reality applications. In our application the real environment has immidiate effects on the virtual objects. It is possible for us to render reflective objects and see our own reflection in the objects, updated 30 times per second. Moreover the virtual objects cast soft shadows on the real floor and on each other. The virtual shadows resemble the real ones because the real light sources are detected in the environment.

Real-Time Global Illumination for Virtual Reality Applications

2015

In this paper we present a system for rendering with real-time global illumination in virtual reality (VR). We describe the virtual light field rendering algorithm and show how it is suitable for real-time VR applications and describe how it is integrated with the XVR sys-tem for real-time GPU-based rendering in a CAVETM. This render-ing method achieves real-time rendering of L(S|D)∗E solutions in time independent of illumination complexity and largely indepen-dent of geometric complexity. The method also supports dynamic changes to scene elements, such as a virtual character that moves through the scene with appropriate shadows and reflections.

Image based shadowing in real-time augmented reality

2006

Abstract—This work presents an approach to render appropriate shadows with Image Based Lighting in Augmented Reality applications. To approximate the result of environment lighting and shadowing, the system uses a dome of shadow casting light sources. The color of each shadow is determined by the area of the environment behind the casting light source. As a result it is possible that changes in the lighting conditions immidiately affect the shadow casting of virtual objects on real objects.

Real-Time Global Illumination for VR Applications

IEEE Computer Graphics and Applications, 2000

In this paper we present a system for rendering with real-time global illumination in virtual reality (VR). We describe the virtual light field rendering algorithm and show how it is suitable for real-time VR applications and describe how it is integrated with the XVR system for real-time GPU-based rendering in a CAVE TM . This rendering method achieves real-time rendering of L(S|D) * E solutions in time independent of illumination complexity and largely independent of geometric complexity. The method also supports dynamic changes to scene elements, such as a virtual character that moves through the scene with appropriate shadows and reflections.

Light factorization for mixed-frequency shadows in augmented reality

2011

Integrating animated virtual objects with their surroundings for high-quality augmented reality requires both geometric and radiometric consistency. We focus on the latter of these problems and present an approach that captures and factorizes external lighting in a manner that allows for realistic relighting of both animated and static virtual objects. Our factorization facilitates a combination of hard and soft shadows, with high-performance, in a manner that is consistent with the surrounding scene lighting.

Integration of real and virtual light sources in augmented reality worlds

2008

A number of issues need to be taken into consideration for the output of an augmented reality application to appear realistic. Such issues include the level of detail of the virtual scene, the accuracy of alignment between the two worlds and the correspondence of illumination between the real and virtual components. This paper reviews registration techniques used to perform the alignment process and discusses a research project that investigates methods matching light conditions. Although a number of registration ...