スケーラブルディスプレイシステムChOWDERとiTownsを⽤いた3D WebGISの超⾼解像度表⽰

2020/10/28
スマートIoT推進フォーラム 技術戦略検討部会 テストベッド分科会
第３回データ分析・可視化タスクフォース

理化学研究所 計算科学研究センター
川鍋友宏 tkawanabe@riken.jp

ChOWDER (The Cooperative Workspace Driver)• A Web-based Scalable Display System for• Team discussions• Remote collaboration among multiple sites• Large scale visualization• Built on modern web technologies• HTML5, JavaScript, P2P-protocols, etc.

Displayable Content Types

Movie(mov, mp4)

WebcamInteractive
Text

PDF

3D GIS(New!)

Image(jpg, png, bmp)

Desktop screen

“VDA” Concept
VDA (Virtual Display Area)• a server managed logical two dimensional display space.
• manages the metadata of physical display devices anddisplaying contents.
Metadata:•••

position on a VDA
magnification ratio on a VDAetc.

This ability to change themagnification of thephysical display is a key
feature of the VDA.

Illustrated of Use Case 1: Co-located Collaboration

Wi-Fi APLANChOWDER-Display

Participants using ChOWDER-Controller

ChOWDER-ServerUse Case 1: Co-located Collaboration

A small satellite (CubeSat) design exercise using concurrent design method.
Image courtesy of Fujii-Tatsukawa Lab., Tokyo University of Science.

Illustrated of Use Case 2: Remote Collaboration

Internet

ChOWDER-Displays
ChOWDER-Display
ChOWDER-ServerSite A

Site B

Use Case 2: Remote Collaboration
HDHD

HDHD

RIKEN R-CCS

4K

4K

4K

4K

Kyusyu Univ.

Contents can be mirrored between remote sites where have different display constitution.

Related Work of Web-based Scalable Display Systeml

SAGE2lA de facto standard in HPC fieldl

Web-based, JavaScript, Node.jsl

Utilizable for remote collaboration

lLimitation on remote collaborationl

All sites need same display configuration
for contents mirroring.
SAGE2
ServerFHD

FHD

FHD

FHD

FHD

site Asite Bsite C

FHD

FHD

FHD

FHD

FHD

FHD

http://sage2.sagecommons.org/wp-content/gallery/misc/sage2-displays-cybercommonspeople.jpg

Tiled Display System @ R-CCS
13

1415

LAN

ChOWDER System @ R-CCS
Web browser

Web browser

Web browser

Web browser(full screen mode)(full screen mode)(full screen mode)(full screen mode)(full screen mode)

Web browser

Web browser

Web browser

Web browser

Web browser(full screen mode)(full screen mode)(full screen mode)(full screen mode)(full screen mode)

Web browser

Web browser

Web browser

Web browser

Web browser(full screen mode)(full screen mode)(full screen mode)(full screen mode)(full screen mode)

Web browser
131415LANWi-Fi
ChOWDER-Controller(Web browser app.)

ChOWDER-Server

A New Feature: 3D Web GIS Viewer

An Example of Viewing 3D Geographic Information by ChOWDER on
a 20K Horizontal Resolution Tiled Display System.
13

Map data published by Geospatial Information Authority of Japan

View Frustum Dividing Using Three.js• To display the 3D content on distributed display should be
divided its view frustum.
• Three.js (a library of JavaScript) has API which enables tooffset of the view frustum.

14

iTowns• Open source 3D Web GIS• Built on Three.js•
enabled camera-offset API.

http://www.itowns-project.org/

Related Work(1)• SAGE2• De fact standard Webbased scalable displaysystem• Can render a Google
maps content span themultiple displays• Google maps is a 2D GIS

http://sage2.sagecommons.org/wp-content/uploads/slideshow-gallery/brazil-rnp-riooffice2-painesage2rnprj.jpg
16eraentlayichthethendcal
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tants
rolgeareng

scalable display system provides a function for the distributed
rendering of Google Maps. However, Google Maps is a 2D
GIS and can be easily realized compared to the distributed
rendering of 3D GIS. Liquid Galaxy [8] was introduced as
distributed rendering software for Google Earth. Currently, it
can also render Cesium [9], an open-source 3D Web GISon multiple displays in a distributed fashion. However, it
has to offset the view frustum by the number of physicalscreens arranged in the cylindrical shape. In other words,
it does not divide a single camera frustum as we proposed•
Introduced
asprovide
distributed
rendering software for Google Earthbut needs
multiple cameras thata different viewpoint
and theshape ofview frustum depicted in Fig.4.
The• sameNeeds
cylindrical-shaped
multi-display
cylindrical-shaped multi-display has the effect of increasing
the immersiveness, but when it displays the same content
on a general flat tiled screen, the perspective of the content
displayed on the screen far from the viewer person becomes
unnatural. In this respect, the method of ChOWDER thatdivides the view frustum and performs distributed rendering
is superior in versatility.

Related Work(2)• Liquid Galaxy

Fig. 4. Comparison of View Frustum Segmentation Methods. Liquid Galaxy(left) and ChOWDER (right).

V. C ONCLUSION AND F UTURE WORK
We introduced the 3D GIS function on ChOWDER, a scalable display system. Based on iTowns, a 3D Web GIS tool, we
implemented a new function to divide a view frustum, whichenabled distributed rendering on multiple display devices. Toexhibit this benefit, we conducted a large-scale 3D GIS data

https://liquidgalaxy.org/img/carousel/0.jpg
17Displaying User-Defined Data on GIS Viewer• Users can overlay their own data on the map view as standard GIS
tools can do.

Showing a typhoon cloud captured by the meteorological satellite converted into
the point-cloud of about 500 million points.
The meteorological satellite data courtesy of The National Institute of Information and Communications Technology and CEReS, Chiba University.
Map data published by Geospatial Information Authority of Japan19

補⾜資料• GitHubにてソースコードとドキュメントを配布• https://github.com/SIPupstreamDesign/ChOWDER• BSD2 ライセンス• “202009”ブランチが最新（開発中）版• 発表済論⽂• Kawanabe, T., Hatta, K., and Ono, K. (2020, September). ChOWDER: A New Approach forViewing 3D Web GIS on Ultra-High-Resolution Scalable Display. In Proceedings of The 2020
IEEE International Conference on Cluster Computing (pp. 412-413).
• KAWANABE, Tomohiro, et al. Showing Ultra-High-Resolution Images in VDA-Based Scalable
Displays. In: International Conference on Cooperative Design, Visualization and Engineering.
Springer, Cham, 2019. p. 116-122.
• Kawanabe, T., Nonaka, J., & Ono, K. (2018, August). Chowder: Dynamic contents sharing throughremote tiled display system. In 11th International Symposium on Visual Information
Communication and Interaction, VINCI 2018 (pp. 108-109). Association for Computing Machinery.