Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | ACM Digital Library |
|---|---|
| Author | Kontkanen, Janne Parker, Evan |
| Abstract | JavaScript is not typically associated with high performance rendering. This talk covers techniques that were used to bring the massive data set of Google Earth into a web browser using standard JavaScript and WebGL. The client has access to a 3d model of the entire world, an ever-growing data set stored in servers, and the client needs to fetch and display any views (see Figures 1 and 2) of it very quickly with a limited memory budget of few tens of megabytes. The total data set, on the other hand is measured in trillions of triangles and their associated textures. The talk describes the hierarchical subdivision and the data layout used to manage this complexity. Level-of-detail mechanisms are used to render objects at different scales and to provide a quick preview when high resolution data is still loading. The unpredictable network bandwidth and latency pose additional challenges. The talk describes the algorithm used to decide which data should be 1) requested, 2) evicted, 3) kept in memory, or 4) rendered. Rendering of map elements such as roads and labels is more challenging in 3d than on a 2d map. The talk describes techniques that were used to render vectors and labels quickly at right location on the surface of the 3d terrain. JavaScript was not originally designed for high performance realtime use. For instance, the garbage collector may kick in at any point pausing the execution for tens of milliseconds. The talk describes the memory management techniques used to avoid this. To optimize for stable frame-rate and quick load time, tasks have to be carefully scheduled such that data processing and rendering can happen seemingly at the same time. The talk describes how the work was scheduled in the main execution thread and in Web Workers. To make the Earth appear realistic, atmospheric attenuation needs to be modeled accurately. The talk describes how the atmosphere and the real-time clouds are rendered. |
| Starting Page | 1 |
| Ending Page | 1 |
| Page Count | 1 |
| File Format | PDF MP4 |
| ISBN | 9781450329606 |
| DOI | 10.1145/2614106.2614194 |
| Language | English |
| Publisher | Association for Computing Machinery (ACM) |
| Publisher Date | 2014-07-27 |
| Publisher Place | New York |
| Access Restriction | Subscribed |
| Subject Keyword | Webgl Real-time rendering Level-of-detail |
| Content Type | Audio Text |
| Resource Type | Article |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|