Max Limper

Fast delivery of 3D web content: a case study

Despite many advances in mesh compression methods within the past two decades, there is still no consensus about a standardized compact mesh encoding format for 3D Web applications. In order to facilitate the design of a future platform-independent solution, this paper investigates the crucial trade-off between compactness of the compressed representation and decompression time. Our case study evaluates different encoding formats, combined with various transmission bandwidths, using different client devices. Results indicate that good compression rates, and at the same time a fast decompression, can be achieved by exploiting existing browser features and by minimizing the complexity of operations that have to be performed inside the JavaScript layer. Our findings are summarized in concrete recommendations for future standards.

The POP Buffer: Rapid Progressive Clustering by Geometry Quantization

Within this paper, we present a novel, straightforward progressive encoding scheme for general triangle soups, which is particularly well-suited for mobile and Web-based environments due to its minimal requirements on the clients hardware and software. Our rapid encoding method uses a hierarchy of quantization to effectively reorder the original primitive data into several nested levels of detail. The resulting stateless buffer can progressively be transferred as-is to the GPU, where clustering is efficiently performed in parallel during rendering. We combine our approach with a crack-free mesh partitioning scheme to obtain a straightforward method for fast streaming and basic view-dependent LOD control.

SRC - a streamable format for generalized web-based 3D data transmission

A problem that still remains with todays technologies for 3D asset transmission is the lack of progressive streaming of all relevant mesh and texture data, with a minimal number of HTTP requests. Existing solutions, like glTF or X3DOMs geometry formats, either send all data within a single batch, or they introduce an unnecessary large number of requests. Furthermore, there is still no established format for a joined, interleaved transmission of geometry data and texture data. Within this paper, we propose a new container file format, entitled Shape Resource Container (SRC). Our format is optimized for progressive, Web-based transmission of 3D mesh data with a minimum number of HTTP requests. It is highly configurable, and more powerful and flexible than previous formats, as it enables a truly progressive transmission of geometry data, partial sharing of geometry between meshes, direct GPU uploads, and an interleaved transmission of geometry and texture data. We also demonstrate how our new mesh format, as well as a wide range of other mesh formats, can be conveniently embedded in X3D scenes, using a new, mini-malistic X3D ExternalGeometry node.

Spatial data structures for accelerated 3D visibility computation to enable large model visualization on the web

The visualization of massive 3D models is an intensively examined field of research. Due to their rapidly growing complexity of such models, visualisation them in real-time will never be possible through a higher speed of rasterization alone. Instead, a practical solution has to reduce the amount of data to be processed, using a fast visibility determination. In recent years, the combination of Javascript and WebGL raised attention for the possibility of rendering hardware-accelerated 3D graphics directly in the browser. However, when compared to desktop applications, they are still fighting with their disadvantages of a generally slower execution speed, or a downgraded set of functionality. We demonstrate the integration of spatial data structures, computed on the client side, using latest technology trends to mitigate the shortcomings of the 3D Web environment. We employ comparably small bounding volume hierarchies to accelerate our visibility determination, as well as to enable specific culling techniques. This allows for an interactive visualization of such massive 3D data sets. Our in-depth analysis of different data structures and environments shows which combination of data structure and visibility determination techniques are currently the best fit for the Web.

webVis/instant3DHub: visual computing as a service infrastructure to deliver adaptive, secure and scalable user centric data visualisation

This paper presents the webVis/instant3DHub platform, which combines a novel Web-Components based framework and a Visual Computing as a Service infrastructure to deliver an interactive 3D data visualisation solution. The system focuses on minimising resource consumption, while maximising the end-user experience. It utilises an adaptive and automated combination of client, server and hybrid visualisation techniques, while orchestrating transmission, caching and rendering services to deliver structural and semantically complex data sets on any device class and network architecture. The API and Web Component framework allow the application developer to compose and manipulate complex data setups with a simple set of commands inside the browser, without requiring knowledge about the underlying service infrastructure, interfaces and the fully automated processes. This results in a new class of interactive applications, built around a canvas for real-time visualisation of massive data sets.

Enhancing the plant layout design process using X3DOM and a scalable web3D service architecture

This paper presents an innovative model-driven architecture enabling 3D web-based design processes in the field of large complex building (LBC) projects, such as power plant construction. This work was motivated by proposing new ways of achieving 3D CAD tasks not only for highly complex and temporary organization in the design stages but also for the whole lifecycle of such installations, which may last several decades. in this particular scenario, it is very important to share the right information with the right stakeholder at the right time, to maintain a high level of knowledge sharing. Taking into account these challenges, we propose a first implementation of interactive 3D CAD editing tools, based on the X3DOM technology and driven by a knowledge layer which utilizes a complete reference data and rules management system. To store the CAD models, a Macro-Parametric Approach has been investigated and a 3D server has been added to the traditional PDM (Product or Plant Data Management) to execute remotely complex CAD operations. This is a very promising start to deploy lightweight and smart web3D CAD editing services for the AEC (Architecture Engineering Construction) and power industries.

Mesh saliency analysis via local curvature entropy

We present a novel approach for estimating mesh saliency. Our method is fast, flexible, and easy to implement. By applying the well-known concept of Shannon entropy to 3D mesh data, we obtain an efficient method to determine mesh saliency. Comparing our method to the most recent, state-of-the-art approach, we show that results of at least similar quality can be achieved within a fraction of the original computation time. We present saliency-guided mesh simplification as a possible application.

Extending a distributed virtual reality system with exchangeable rendering back-ends

We present an approach to integrate multiple rendering back-ends under a common application layer for distributed systems. The primary goal was to find a practical and nonintrusive way to use potentially very different renderers in heterogeneous computing environments without impairing their strengths and without burdening the back-ends or the application with details of the cluster environment. Our approach is based on a mediator layer that handles multithreading, clustering, and the synchronization between the application’s and the back-end’s scene. We analyze the proposed approach with an implementation for a state-of-the-art distributed VR/AR system. In particular, we present two case studies and an example application.

A unified GLTF/X3D extension to bring physically-based rendering to the web

We present a unified material description and transmission format for real-time, physically-based shading. Our format is general enough to be used consistently across multiple rendering systems and platforms, covering a wide range of applications from desktop to Web. Furthermore, our formats expressiveness allows to represent a wide variety of real-world materials. First, we define a common parameter set for physically-based shading in modern, real-time 3D graphics systems. We then demonstrate its applicability for several types of materials on different rendering systems. Finally, we propose a transmission format, in the form of extensions for the glTF and X3D standards.

Evaluating 3D thumbnails for virtual object galleries

Virtual 3D object galleries on the Web nowadays often use real-time, interactive 3D graphics. However, this does usually still not hold for their preview images, sometimes referred to as thumbnails. We provide a technical analysis on the applicability of so-called 3D thumbnails within the context virtual 3D object galleries. Like a 2D thumbnail for an image, a 3D thumbnail acts as a compact preview for a real 3D model. In contrast to an image series, however, it enables a wider variety of interaction methods and rendering effects. By performing a case study, we show that such true 3D representations are, under certain circumstances, even able to outperform 2D image series in terms of bandwidth consumption. We thus present a complete pipeline for generating compact 3D thumbnails for given meshes in a fully automatic fashion.