Animation on the web: a survey
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paper_title: Representing Progressive Dynamic 3D Meshes and Applications

paper_content:

Dynamic 3D mesh sequences, also called 3D animation, have been widely used in the movie and gaming industries. However, the huge storage requirements of dynamic mesh data make it problematic for a number of applications such as rendering, transmission over a network, and displaying on mobile devices. This paper proposes a multi resolution representation of 3D animation that results displaying 3D animation progressively. The proposed method transforms traditional 3D animation representation into progressive representation, which takes up less storage and memory space. The progressive representation is constructed by compressing the animation into a base animation with sequenced refining operators. The base animation is viewable and can be reconstructed by transmitting for only a few seconds, which is also called thumbnail animation in this paper, the more detailed animation can be refined smoothly with applying refining operators. As the results, the resolution of animation can be free to change at real-time, where the resolution can be increased automatically or even controlled by user. Moreover, the progressive animation is more suitable for transmitting and displaying through the network.
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paper_title: Displaced dynamic expression regression for real-time facial tracking and animation

paper_content:

We present a fully automatic approach to real-time facial tracking and animation with a single video camera. Our approach does not need any calibration for each individual user. It learns a generic regressor from public image datasets, which can be applied to any user and arbitrary video cameras to infer accurate 2D facial landmarks as well as the 3D facial shape from 2D video frames. The inferred 2D landmarks are then used to adapt the camera matrix and the user identity to better match the facial expressions of the current user. The regression and adaptation are performed in an alternating manner. With more and more facial expressions observed in the video, the whole process converges quickly with accurate facial tracking and animation. In experiments, our approach demonstrates a level of robustness and accuracy on par with state-of-the-art techniques that require a time-consuming calibration step for each individual user, while running at 28 fps on average. We consider our approach to be an attractive solution for wide deployment in consumer-level applications.
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paper_title: Predictive compression of dynamic 3D meshes

paper_content:

An efficient algorithm for compression of dynamic time-consistent 3D meshes is presented. Such a sequence of meshes contains a large degree of temporal statistical dependencies that can be exploited for compression using DPCM. The vertex positions are predicted at the encoder from a previously decoded mesh. The difference vectors are further clustered in an octree approach. Only a representative for a cluster of difference vectors is further processed providing a significant reduction of data rate. The representatives are scaled and quantized and finally entropy coded using CABAC, the arithmetic coding technique used in H.264/MPEG4-AVC. The mesh is then reconstructed at the encoder for prediction of the next mesh. In our experiments we compare the efficiency of the proposed algorithm in terms of bit-rate and quality compared to static mesh coding and interpolator compression indicating a significant improvement in compression efficiency.
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paper_title: Static 3D triangle mesh compression overview

paper_content:

3D triangle meshes are extremely used to model discrete surfaces, and almost always represented with two tables: one for geometry and another for connectivity. While the raw size of a triangle mesh is of around 200 bits per vertex, by coding cleverly (and separately) those two distinct kinds of information it is possible to achieve compression ratios of 15:1 or more. Different techniques must be used depending on whether single-rate vs. progressive bitstreams are sought; and, in the latter case, on whether or not hierarchically nested meshes are desirable during reconstruction.
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paper_title: Blast: a binary large structured transmission format for the web

paper_content:

Recent advances in Web technology, especially real-time 3D content using WebGL, require an efficient way to transfer binary data. Images, audio and video have respective HTML tags and accompanying data formats that transparently handle binary transmission and decompression. 3D data, on the other hand, has to be handled explicitly by the client application. In contrast to images, audio and video, 3D data is inhomogeneous and neither common formats nor compression algorithms have been established for the Web. Despite the many existing formats for binary transmission of 3D data none has been able to provide a general binary format for all kinds of 3D data including meshes, textures, animations, and materials. Existing formats are domain-specific and fixed on a certain set of input data and thus too specific to handle other types of data. Blast is a general container format for structured binary transmission on the Web that can be used for all types of 3D scene data. Instead of defining a fixed set of encodings and compression algorithms Blast exploits the code on demand paradigm to provide a simple yet powerful encoder-agnostic basis to leverage existing domain-specific solutions and compression techniques. Because streaming is of primary importance for a good user experience Blast is designed on the basis of self-contained chunks to enable JavaScript clients to utilize Web Workers for parallel decoding and to provide early feedback to the user.
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paper_title: Streaming compressed 3D data on the web using JavaScript and WebGL

paper_content:

With the development of Web3D technologies, the delivery and visualization of 3D models on the web is now possible and is bound to increase both in the industry and for the general public. However the interactive remote visualization of 3D graphic data in a web browser remains a challenging issue. Indeed, most of existing systems suffer from latency (due to the data downloading time) and lack of adaptation to heterogeneous networks and client devices (i.e. the lack of levels of details); these drawbacks seriously affect the quality of user experience. This paper presents a technical solution for streaming and visualization of compressed 3D data on the web. Our approach leans upon three strong features: (1) a dedicated progressive compression algorithm for 3D graphic data with colors producing a binary compressed format which allows a progressive decompression with several levels of details; (2) the introduction of a JavaScript halfedge data structure allowing complex geometrical and topological operations on a 3D mesh; (3) the multi-thread JavaScript/WebGL implementation of the decompression scheme allowing 3D data streaming in a web browser. Experiments and comparison with existing solutions show promising results in terms of latency, adaptability and quality of user experience.
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paper_title: SRC - a streamable format for generalized web-based 3D data transmission

paper_content:

A problem that still remains with today's 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 X3DOM's 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.
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paper_title: Progressive Animation Sequences

paper_content:

3D animations have been widely used in the movie and gaming industries. However, the huge storage requirements of dynamic mesh data make it difficult for a number of applications such as rendering, transmitting over a network, etc.This study proposes a multiresolution representation for 3D animation. The results show that the coarse animation appears by using only 10% of the original faces. More detailed animation appears by using 80% of original faces, but only requires 3% of original storage space. Consequently, this approach enables a continuous level of detail for dynamic 3D mesh sequences.
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paper_title: Mesh Geometry Compression for Mobile Graphics

paper_content:

This paper presents a compression scheme for mesh geometry, which is suitable for mobile graphics. The main focus is to enable real-time decoding of compressed vertex positions while providing reasonable compression ratios. Our scheme is based on local quantization of vertex positions with mesh partitioning. To prevent visual seams along the partitioning boundaries, we constrain the locally quantized cells of all mesh partitions to have the same size and aligned local axes. We propose a mesh partitioning algorithm to minimize the size of locally quantized cells, which relates to the distortion of a restored mesh. Vertex coordinates are stored in main memory and transmitted to graphics hardware for rendering in the quantized form, saving memory space and system bus bandwidth. Decoding operation is combined with model geometry transformation, and the only overhead to restore vertex positions is one matrix multiplication for each mesh partition.
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paper_title: Feature Oriented Progressive Lossless Mesh Coding

paper_content:

A feature-oriented generic progressive lossless mesh coder (FOLProM) is proposed to encode triangular meshes with arbitrarily complex geometry and topology. In this work, a sequence of levels of detail (LODs) are generated through iterative vertex set split and bounding volume subdivision. The incremental geometry and connectivity updates associated with each vertex set split and/or bounding volume subdivision are entropy coded. Due to the visual importance of sharp geometric features, the whole geometry coding process is optimized for a better presentation of geometric features, especially at low coding bitrates. Feature-oriented optimization in FOLProM is performed in hierarchy control and adaptive quantization. Efficient coordinate representation and prediction schemes are employed to reduce the entropy of data significantly. Furthermore, a simple yet efficient connectivity coding scheme is proposed. It is shown that FOLProM offers a significant rate-distortion (R-D) gain over the prior art, which is especially obvious at low bitrates.
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paper_title: Progressive Animation Sequences

paper_content:

3D animations have been widely used in the movie and gaming industries. However, the huge storage requirements of dynamic mesh data make it difficult for a number of applications such as rendering, transmitting over a network, etc.This study proposes a multiresolution representation for 3D animation. The results show that the coarse animation appears by using only 10% of the original faces. More detailed animation appears by using 80% of original faces, but only requires 3% of original storage space. Consequently, this approach enables a continuous level of detail for dynamic 3D mesh sequences.
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paper_title: Geometry videos: a new representation for 3D animations

paper_content:

We present the "Geometry Video," a new data structure to encode animated meshes. Being able to encode animated meshes in a generic source-independent format allows people to share experiences. Changing the viewpoint allows more interaction than the fixed view supported by 2D video. Geometry videos are based on the "Geometry Image" mesh representation introduced by Gu et al. 4. Our novel data structure provides a way to treat an animated mesh as a video sequence (i.e., 3D image) and is well suited for network streaming. This representation also offers the possibility of applying and adapting existing mature video processing and compression techniques (such as MPEG encoding) to animated meshes. This paper describes an algorithm to generate geometry videos from animated meshes.The main insight of this paper, is that Geometry Videos re-sample and re-organize the geometry information, in such a way, that it becomes very compressible. They provide a unified and intuitive method for level-of-detail control, both in terms of mesh resolution (by scaling the two spatial dimensions) and of frame rate (by scaling the temporal dimension). Geometry Videos have a very uniform and regular structure. Their resource and computational requirements can be calculated exactly, hence making them also suitable for applications requiring level of service guarantees.
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paper_title: Progressive compression for lossless transmission of triangle meshes

paper_content:

Lossless transmission of 3D meshes is a very challenging and timely problem for many applications, ranging from collaborative design to engineering. Additionally, frequent delays in transmissions call for progressive transmission in order for the end user to receive useful successive refinements of the final mesh. In this paper, we present a novel, fully progressive encoding approach for lossless transmission of triangle meshes with a very fine granularity. A new valence-driven decimating conquest, combined with patch tiling and an original strategic retriangulation is used to maintain the regularity of valence. We demonstrate that this technique leads to good mesh quality, near-optimal connectivity encoding, and therefore a good rate-distortion ratio throughout the transmission. We also improve upon previous lossless geometry encoding by decorrelating the normal and tangential components of the surface. For typical meshes, our method compresses connectivity down to less than 3.7 bits per vertex, 40% better in average than the best methods previously reported [5, 18]; we further reduce the usual geometry bit rates by 20% in average by exploiting the smoothness of meshes. Concretely, our technique can reduce an ascii VRML 3D model down to 1.7% of its size for a 10-bit quantization (2.3% for a 12-bit quantization) while providing a very progressive reconstruction.
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paper_title: A progressive view-dependent technique for interactive 3-D mesh transmission

paper_content:

A view-dependent graphics streaming scheme is proposed in this work that facilitates interactive streaming and browsing of three-dimensional (3-D) graphics models. First, a 3-D model is split into several partitions. Second, each partition is simplified and coded independently. Finally, the compressed data is sent in order of relevance to the user's requests to maximize visual quality. Specifically, the server can transmit visible parts in detail, while cutting out invisible parts. Experimental results demonstrate that the proposed algorithm reduces the required transmission bandwidth, and provides an acceptable visual quality even at low bit rates.
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paper_title: Static 3D triangle mesh compression overview

paper_content:

3D triangle meshes are extremely used to model discrete surfaces, and almost always represented with two tables: one for geometry and another for connectivity. While the raw size of a triangle mesh is of around 200 bits per vertex, by coding cleverly (and separately) those two distinct kinds of information it is possible to achieve compression ratios of 15:1 or more. Different techniques must be used depending on whether single-rate vs. progressive bitstreams are sought; and, in the latter case, on whether or not hierarchically nested meshes are desirable during reconstruction.
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paper_title: Geometry images

paper_content:

Surface geometry is often modeled with irregular triangle meshes. The process of remeshing refers to approximating such geometry using a mesh with (semi)-regular connectivity, which has advantages for many graphics applications. However, current techniques for remeshing arbitrary surfaces create only semi-regular meshes. The original mesh is typically decomposed into a set of disk-like charts, onto which the geometry is parametrized and sampled. In this paper, we propose to remesh an arbitrary surface onto a completely regular structure we call a geometry image. It captures geometry as a simple 2D array of quantized points. Surface signals like normals and colors are stored in similar 2D arrays using the same implicit surface parametrization --- texture coordinates are absent. To create a geometry image, we cut an arbitrary mesh along a network of edge paths, and parametrize the resulting single chart onto a square. Geometry images can be encoded using traditional image compression algorithms, such as wavelet-based coders.
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paper_title: 3D graphics on the web: A survey

paper_content:

Abstract In recent years, 3D graphics has become an increasingly important part of the multimedia web experience. Following on from the advent of the X3D standard and the definition of a declarative approach to presenting 3D graphics on the web, the rise of WebGL has allowed lower level access to graphics hardware of ever increasing power. In parallel, remote rendering techniques permit streaming of high-quality 3D graphics onto a wide range of devices, and recent years have also seen much research on methods of content delivery for web-based 3D applications. All this development is reflected in the increasing number of application fields for the 3D web. In this paper, we reflect this activity by presenting the first survey of the state of the art in the field. We review every major approach to produce real-time 3D graphics rendering in the browser, briefly summarise the approaches for remote rendering of 3D graphics, before surveying complementary research on data compression methods, and notable application fields. We conclude by assessing the impact and popularity of the 3D web, reviewing the past and looking to the future.
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paper_title: View-dependent refinement of progressive meshes

paper_content:

Level-of-detail (LOD) representations are an important tool for realtime rendering of complex geometric environments. The previously introduced progressive mesh representation defines for an arbitrary triangle mesh a sequence of approximating meshes optimized for view-independent LOD. In this paper, we introduce a framework for selectively refining an arbitrary progressive mesh according to changing view parameters. We define efficient refinement criteria based on the view frustum, surface orientation, and screen-space geometric error, and develop a real-time algorithm for incrementally refining and coarsening the mesh according to these criteria. The algorithm exploits view coherence, supports frame rate regulation, and is found to require less than 15% of total frame time on a graphics workstation. Moreover, for continuous motions this work can be amortized over consecutive frames. In addition, smooth visual transitions (geomorphs) can be constructed between any two selectively refined meshes. A number of previous schemes create view-dependent LOD meshes for height fields (e.g. terrains) and parametric surfaces (e.g. NURBS). Our framework also performs well for these special cases. Notably, the absence of a rigid subdivision structure allows more accurate approximations than with existing schemes. We include results for these cases as well as for general meshes. CR Categories: I.3.3 [Computer Graphics]: Picture/Image Generation Display algorithms; I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling surfaces and object representations. Additional
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paper_title: Surface simplification using quadric error metrics

paper_content:

Many applications in computer graphics require complex, highly detailed models. However, the level of detail actually necessary may vary considerably. To control processing time, it is often desirable to use approximations in place of excessively detailed models. We have developed a surface simplification algorithm which can rapidly produce high quality approximations of polygonal models. The algorithm uses iterative contractions of vertex pairs to simplify models and maintains surface error approximations using quadric matrices. By contracting arbitrary vertex pairs (not just edges), our algorithm is able to join unconnected regions of models. This can facilitate much better approximations, both visually and with respect to geometric error. In order to allow topological joining, our system also supports non-manifold surface models. CR Categories: I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling—surface and object representations
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paper_title: Blast: a binary large structured transmission format for the web

paper_content:

Recent advances in Web technology, especially real-time 3D content using WebGL, require an efficient way to transfer binary data. Images, audio and video have respective HTML tags and accompanying data formats that transparently handle binary transmission and decompression. 3D data, on the other hand, has to be handled explicitly by the client application. In contrast to images, audio and video, 3D data is inhomogeneous and neither common formats nor compression algorithms have been established for the Web. Despite the many existing formats for binary transmission of 3D data none has been able to provide a general binary format for all kinds of 3D data including meshes, textures, animations, and materials. Existing formats are domain-specific and fixed on a certain set of input data and thus too specific to handle other types of data. Blast is a general container format for structured binary transmission on the Web that can be used for all types of 3D scene data. Instead of defining a fixed set of encodings and compression algorithms Blast exploits the code on demand paradigm to provide a simple yet powerful encoder-agnostic basis to leverage existing domain-specific solutions and compression techniques. Because streaming is of primary importance for a good user experience Blast is designed on the basis of self-contained chunks to enable JavaScript clients to utilize Web Workers for parallel decoding and to provide early feedback to the user.
---
paper_title: Enhancing X3DOM declarative 3D with rigid body physics support

paper_content:

Given that physics can be fundamental for realistic and interactive Web3D applications, a number of JavaScript versions of physics engines have been introduced during the past years. This paper presents the implementation of the rigid body physics component, as defined by the X3D specification, in the X3DOM environment, and the creation of dynamic 3D interactive worlds. We briefly review the state of the art in current technologies for Web3D graphics, including HTML5, WebGL and X3D, and then explore the significance of physics engines in building realistic Web3D worlds. We include a comprehensive review of JavaScript physics engine libraries, and proceed to summarize the significance of our implementation while presenting in detail the methodology followed. The results obtained so far from our cross-browser experiments demonstrate that real-time interactive scenes with hundreds of rigid bodies can be constructed and operate with acceptable frame rates, while the allowing the user to maintain the scene control.
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paper_title: Deformation Sensitive Decimation

paper_content:

In computer graphics, many automatic methods for simplifying polygonal meshes have been developed. These techniques work very well for static meshes; however, they do not handle the case of deforming objects. Simplifying any single pose of a deforming object may destroy detail required to represent the shape in a different pose. We present an automatic technique for simplifying deforming character meshes that takes a set of examples as input and produces a set of simplied examples as output. The method preserves detail required for deformation and maintains connectivity information across the examples. This technique is applicable to many current skinning algorithms including example-driven techniques, tting techniques and Linear Blend Skinning.
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paper_title: Multi-Layer Level of Detail For Character Animation

paper_content:

Real-time animation of human-like characters has been an active research area in computer graphics. Nowadays, more and more applications need to render various realistic scenes with human motion in crowds for interactive virtual environments. Animation and level of detail are well explored fields but little has been done to generate level of detail automatically for dynamic articulated meshes. Our approach is based on the combination of three interesting layers for run-time level of detail in character crowd animation: the skeleton, the mesh and the motion. We build a Multiresolution Skeletal Graph to simplify the skeleton topology progressively. In contrast with previous works, we use a Dual-Graph Based Simplification for articulated meshes, where the triangle decimation is driven by triangle compactness, to build a dynamic, continuous, progressive and selective mesh level of detail. We also present Power Skinning to ensure the stability of Linear Smooth Skinning, during the simplification, with an efficient multi-weight update rule.
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paper_title: SRC - a streamable format for generalized web-based 3D data transmission

paper_content:

A problem that still remains with today's 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 X3DOM's 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.
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paper_title: LPM: lightweight progressive meshes towards smooth transmission of Web3D media over internet

paper_content:

Transmission of Web3D media over the Internet can be slow, especially when downloading huge 3D models through relatively limited bandwidth. Currently, 3D compression and progressive meshes are used to alleviate the problem, but these schemes do not consider similarity among the 3D components, leaving rooms for improvement in terms of efficiency. This paper proposes a similarity-aware 3D model reduction method, called Lightweight Progressive Meshes (LPM). The key idea of LPM is to search similar components in a 3D model, and reuse them through the construction of a Lightweight Scene Graph (LSG). The proposed LPM offers three significant benefits. First, the size of 3D models can be reduced for transmission without almost any precision loss of the original models. Second, when rendering, decompression is not needed to restore the original model, and instanced rendering can be fully exploited. Third, it is extremely efficient under very limited bandwidth, especially when transmitting large 3D scenes. Performance on real data justifies the effectiveness of our LPM, which improves the state-of-the-art in Web3D media transmission.
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paper_title: Surface simplification using quadric error metrics

paper_content:

Many applications in computer graphics require complex, highly detailed models. However, the level of detail actually necessary may vary considerably. To control processing time, it is often desirable to use approximations in place of excessively detailed models. We have developed a surface simplification algorithm which can rapidly produce high quality approximations of polygonal models. The algorithm uses iterative contractions of vertex pairs to simplify models and maintains surface error approximations using quadric matrices. By contracting arbitrary vertex pairs (not just edges), our algorithm is able to join unconnected regions of models. This can facilitate much better approximations, both visually and with respect to geometric error. In order to allow topological joining, our system also supports non-manifold surface models. CR Categories: I.3.5 [Computer Graphics]: Computational Geometry and Object Modeling—surface and object representations
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paper_title: Progressive skinning for video game character animations

paper_content:

The cartridge is made of plastic material and comprises a shell having an exit slot and end covers mounted at the ends of said shell. The cartridge consists of three substantially semicylindrical members, which by means of two hinges are connected to each other so that two semicylindrical members when folded together constitute a shell which encloses the roll of film and the third semicylindrical member covers said shell and defines a film passage in the shape of an arc of a circle, and the exit slot of the cartridge, and the two outer semicylindrical members are interconnected.
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paper_title: Coarse-grained multiresolution structures for mobile exploration of gigantic surface models

paper_content:

We discuss our experience in creating scalable systems for distributing and rendering gigantic 3D surfaces on web environments and common handheld devices. Our methods are based on compressed streamable coarse-grained multiresolution structures. By combining CPU and GPU compression technology with our multiresolution data representation, we are able to incrementally transfer, locally store and render with unprecedented performance extremely detailed 3D mesh models on WebGL-enabled browsers, as well as on hardware-constrained mobile devices.
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paper_title: Instant texture transmission using bandwidth-optimized progressive interlacing images

paper_content:

We present an adaptive bandwidth-optimized approach for progressive image transmission to allow instant textured rendering in web-based 3D applications. Applications utilizing a lot of image data require an adaptive technology to build responsive user interfaces. This applies especially for the use in mobile networks. While several approaches provide a progressive geometry streaming, they do not focus on a fast and simple texture streaming for 3D web applications. However, standard 2D image transmission technologies are usually inappropriate within a 3D context. In 2D, image size as well as resolution are often set during the authoring phase, whereas in 3D applications size and displayed resolution of textured 3D objects depend on the virtual camera. An adaptive texture transmission mechanism has to consider this as part of its control function. Our approach thus combines progressive texture streaming with an adaptive number of refinement levels without any pixel retransmission. It enables a fast user feedback and reduces the transmitted data to a minimum without loss of visual quality. Moreover, our GPUII approach (GPU-based Image Interlacing) allows an easy integration into existing applications while also reducing the CPU load.
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paper_title: Spatial data structures for accelerated 3D visibility computation to enable large model visualization on the web

paper_content:

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.
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paper_title: Progressive Compression of Manifold Polygon Meshes

paper_content:

This paper presents a new algorithm for the progressive compression of manifold polygon meshes. The input surface is decimated by several traversals that generate successive levels of detail through a specific patch decimation operator which combines vertex removal and local remeshing. The mesh connectivity is encoded by two lists of Boolean error predictions based on the mesh geometry: one for the inserted edges and the other for the faces with a removed center vertex. The mesh geometry is encoded with a barycentric error prediction of the removed vertex coordinates and a local curvature prediction. We also include two methods that improve the rate-distortion performance: a wavelet formulation with a lifting scheme and an adaptive quantization technique. Experimental results demonstrate the effectiveness of our approach in terms of compression rates and rate-distortion performance.
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paper_title: Enhancing X3DOM declarative 3D with rigid body physics support

paper_content:

Given that physics can be fundamental for realistic and interactive Web3D applications, a number of JavaScript versions of physics engines have been introduced during the past years. This paper presents the implementation of the rigid body physics component, as defined by the X3D specification, in the X3DOM environment, and the creation of dynamic 3D interactive worlds. We briefly review the state of the art in current technologies for Web3D graphics, including HTML5, WebGL and X3D, and then explore the significance of physics engines in building realistic Web3D worlds. We include a comprehensive review of JavaScript physics engine libraries, and proceed to summarize the significance of our implementation while presenting in detail the methodology followed. The results obtained so far from our cross-browser experiments demonstrate that real-time interactive scenes with hundreds of rigid bodies can be constructed and operate with acceptable frame rates, while the allowing the user to maintain the scene control.
---
paper_title: 3D graphics on the web: A survey

paper_content:

Abstract In recent years, 3D graphics has become an increasingly important part of the multimedia web experience. Following on from the advent of the X3D standard and the definition of a declarative approach to presenting 3D graphics on the web, the rise of WebGL has allowed lower level access to graphics hardware of ever increasing power. In parallel, remote rendering techniques permit streaming of high-quality 3D graphics onto a wide range of devices, and recent years have also seen much research on methods of content delivery for web-based 3D applications. All this development is reflected in the increasing number of application fields for the 3D web. In this paper, we reflect this activity by presenting the first survey of the state of the art in the field. We review every major approach to produce real-time 3D graphics rendering in the browser, briefly summarise the approaches for remote rendering of 3D graphics, before surveying complementary research on data compression methods, and notable application fields. We conclude by assessing the impact and popularity of the 3D web, reviewing the past and looking to the future.
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paper_title: An event-based framework for animations in X3D

paper_content:

Animations are frequently used and beneficial for different scenarios in information visualization [Robertson et al. 2008; Kriglstein et al. 2012]. The X3D format [ISO and IEC 2008] provides a sound basis to create information visualizations and animations, but its concept of routes, interpolators and sensors for animating elements has some weaknesses. A major problem is that X3D has no built-in event-based mechanism to trigger reusable complex animations. The widespread use of the event-based approach in web technology shows, that it is an efficient concept adaptable to different needs. The lack of such a mechanism in X3D makes it difficult in some scenarios to create animated and interactive scenes. This paper will show a concept capable of solving these problems in X3D and the implementation of the concept as a framework. The framework helps to create dynamic information visualization scenes and makes it possible to create and combine reusable animations. Furthermore the framework provides ways to trigger these animations at given times to orchestrate the animations of a scene. The triggering mechanism also has the advantage to separate the animations from the static aspects of a scene.
---
paper_title: Enhancing X3DOM declarative 3D with rigid body physics support

paper_content:

Given that physics can be fundamental for realistic and interactive Web3D applications, a number of JavaScript versions of physics engines have been introduced during the past years. This paper presents the implementation of the rigid body physics component, as defined by the X3D specification, in the X3DOM environment, and the creation of dynamic 3D interactive worlds. We briefly review the state of the art in current technologies for Web3D graphics, including HTML5, WebGL and X3D, and then explore the significance of physics engines in building realistic Web3D worlds. We include a comprehensive review of JavaScript physics engine libraries, and proceed to summarize the significance of our implementation while presenting in detail the methodology followed. The results obtained so far from our cross-browser experiments demonstrate that real-time interactive scenes with hundreds of rigid bodies can be constructed and operate with acceptable frame rates, while the allowing the user to maintain the scene control.
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paper_title: A scalable architecture for the HTML5/X3D integration model X3DOM

paper_content:

We present a scalable architecture, which implements and further evolves the HTML/X3D integration model X3DOM introduced in [Behr et al. 2009]. The goal of this model is to integrate and update declarative X3D content directly in the HTML DOM tree. The model was previously presented in a very abstract and generic way by only suggesting implementation strategies. The available open-source x3dom.js architecture provides concrete solutions to the previously open points and extents the generic model if necessary. The outstanding feature of the architecture is to provide a single declarative interface to application developers and at the same time support of various backends through a powerful fallback-model. This fallback-model does not provide a single implementation strategy for the runtime and rendering module but supports different methods transparently. This includes native browser implementations and X3D-plugins as well as a WebGL-based scene-graph, which allows running the content without the need for installing additional plugins on all browsers that support WebGL. The paper furthermore discusses generic aspects of the architecture like encoding and introspection, but also provides details concerning two backends. It shows how the system interfaces with X3D-plugins and WebGL and also discusses implementation specific features and limitations.
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paper_title: Declarative AR in the Web with XML3D and Xflow

paper_content:

Augmented Reality is about enhancing video streams from the real world with dynamic, interactive, rich-media content. We propose that HTML5 browsers (the de-facto runtime-engines and viewers for dynamic, interactive, rich-media 2D environments) are becoming ideal AR engines ‐ when extended with support for dynamic and interactive 3D content as well as efficient image and computer vision processing. Early but fully functional prototypes have already been developed using our XML3D and Xflow technology and will be demonstrated. Modern Web technologies already provide native support for hardware-accelerated 3D graphics (WebGL) as well as access to cameras and many other sensors. Recently, JavaScript implementations in browsers became significantly faster (e.g. with asm.js) and upcoming extensions like WebCL (Khronos) or Parallel-Javascript/RiverTrail (Intel/Mozilla) promise to make massively parallel computing readily available within the browser as well. This enables efficient image processing, feature detection, and tracking, but also real-time animations and other compute intensive processing ‐ right within the browser. As a result, it is now becoming possible to design Web-based AR applications that completely run in any modern Web browser without extensions or plug-ins. Such AR applications can take full advantage of the browsers rich-media environment and benefit from the Webs huge ecosystem, such as cloud computing, service-oriented architectures, Open Linked Data, and many more. This would enable millions of Web Developers to easily integrate AR technology directly into their Web applications. Web browsers will provide AR at your fingertips: A single click on a URL can fully immerse the user in arbitrary AR experiences even on mobile devices. We show how XML3D, an extension to HTML5 for declarative 3D graphics, and Xflow, a declarative language for dataflow processing, provide a high-level framework to develop AR applications on the Web, while encapsulating and abstracting from low-level image and AR processing. Our approach does not provide functionality as a large, monolithic library, but rather as a collection of smaller building-blocks that can flexibly be combined and reused in many ways depending on the needs of applications and developers. We also show how AR operators can be accelerated in the browser with emerging Web technologies such as Parallel JavaScript (RiverTrail).
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paper_title: Spatial data structures for accelerated 3D visibility computation to enable large model visualization on the web

paper_content:

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.
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paper_title: Interactive visualization of volumetric data with WebGL in real-time

paper_content:

This article presents and discusses the implementation of a direct volume rendering system for the Web, which articulates a large portion of the rendering task in the client machine. By placing the rendering emphasis in the local client, our system takes advantage of its power, while at the same time eliminates processing from unreliable bottlenecks (e.g. network). The system developed articulates in efficient manner the capabilities of the recently released WebGL standard, which makes available the accelerated graphic pipeline (formerly unusable). The dependency on specially customized hardware is eliminated, and yet efficient rendering rates are achieved. The Web increasingly competes against desktop applications in many scenarios, but the graphical demands of some of the applications (e.g. interactive scientific visualization by volume rendering), have impeded their successful settlement in Web scenarios. Performance, scalability, accuracy, security are some of the many challenges that must be solved before visual Web applications popularize. In this publication we discuss both performance and scalability of the volume rendering by WebGL ray-casting in two different but challenging application domains: medical imaging and radar meteorology.
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paper_title: Enhancing X3DOM declarative 3D with rigid body physics support

paper_content:

Given that physics can be fundamental for realistic and interactive Web3D applications, a number of JavaScript versions of physics engines have been introduced during the past years. This paper presents the implementation of the rigid body physics component, as defined by the X3D specification, in the X3DOM environment, and the creation of dynamic 3D interactive worlds. We briefly review the state of the art in current technologies for Web3D graphics, including HTML5, WebGL and X3D, and then explore the significance of physics engines in building realistic Web3D worlds. We include a comprehensive review of JavaScript physics engine libraries, and proceed to summarize the significance of our implementation while presenting in detail the methodology followed. The results obtained so far from our cross-browser experiments demonstrate that real-time interactive scenes with hundreds of rigid bodies can be constructed and operate with acceptable frame rates, while the allowing the user to maintain the scene control.
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paper_title: An event-based framework for animations in X3D

paper_content:

Animations are frequently used and beneficial for different scenarios in information visualization [Robertson et al. 2008; Kriglstein et al. 2012]. The X3D format [ISO and IEC 2008] provides a sound basis to create information visualizations and animations, but its concept of routes, interpolators and sensors for animating elements has some weaknesses. A major problem is that X3D has no built-in event-based mechanism to trigger reusable complex animations. The widespread use of the event-based approach in web technology shows, that it is an efficient concept adaptable to different needs. The lack of such a mechanism in X3D makes it difficult in some scenarios to create animated and interactive scenes. This paper will show a concept capable of solving these problems in X3D and the implementation of the concept as a framework. The framework helps to create dynamic information visualization scenes and makes it possible to create and combine reusable animations. Furthermore the framework provides ways to trigger these animations at given times to orchestrate the animations of a scene. The triggering mechanism also has the advantage to separate the animations from the static aspects of a scene.
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paper_title: Spatial data structures for accelerated 3D visibility computation to enable large model visualization on the web

paper_content:

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.
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Title: Animation on the Web: A Survey

Section 1: What is Animation?
Description 1: Discusses the definition and types of animation, with a focus on real-time rendering and transmission of animation data on the web.

Section 2: Animation of Static Objects
Description 2: Explores the methods and principles behind animating static objects, primarily using geometric transformations and numerical integration.

Section 3: Animation of Deformable Objects
Description 3: Discusses the animation of objects that change shape or volume due to external forces, and the different approaches for animating deformable objects.

Section 4: Overview Of The Challenges
Description 4: Outlines the unique challenges and requirements of web-based animation, including data transmission, compression, and rendering complexities.

Section 5: Transmission Of Data
Description 5: Covers the technical aspects of transmitting 3D animation data over the internet, emphasizing the issues of latency, bandwidth, and the need for structured formats.

Section 6: Compression & Preprocessing
Description 6: Describes the techniques for compressing and preprocessing animation data to make it suitable for transmission and real-time rendering.

Section 7: Rendering
Description 7: Surveys the principal rendering contexts and technologies for web-based animations, including a discussion of WebGL and related APIs.

Section 8: Transmission over the Web
Description 8: Compares various methods and formats for transmitting animation data over the web, focusing on practical solutions and current technologies.

Section 9: How existing formats and/or libraries deal with Animation
Description 9: Reviews existing file formats and libraries, assessing their approach to handling animation data on the web.

Section 10: Parallelism in JavaScript
Description 10: Examines approaches to enhance JavaScript performance for handling large animation data through parallelism and GPU processing.

Section 11: Conclusion
Description 11: Summarizes the current state and future prospects of animation on the web, identifying open challenges and potential directions for further research.