Paul OBERMEIER (Private, Germany)

Keywords: Tcl/Tk, Tcl3D, OpenGL, OpenSceneGraph

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Tcl3D is an extension exposing the functionality of OpenGL and various other low-level 3D graphics APIs at the Tcl scripting level. Since it's first version - a basic OpenGL wrapper - presented to the Tcl community at TclEurope 2005, it has been extended to support full OpenGL functionality, shading languages like GLSL and Cg, 3D text and various other low-level 3D functionalities.

To bring Tcl based 3D graphics to a higher abstraction level, i.e. deal with 3-dimensional objects instead of just polygons, a scene graph based structure is introduced as a new Tcl3D module. The functionality for structured hierarchies of 3D objects is provided by the OpenSceneGraph library.

The presentation starts with a short overview of the Tcl3D evolution since 2005. An exclusive preview of the state and techniques used for wrapping the OpenSceneGraph library will be given afterwards. Several OpenSceneGraph based demonstration programs will complete the presentation.

Daniel STEFFEN (Independant, Switzerland)

Keywords: Tcl, Mac OS X, notifier, embedding

Download presentation and demo files: (61K), demo files (.zip, 3600K)

Tcl 8.5.7 introduces a rearchitected Mac OS X notifier that allows Tcl to be embedded into native Mac OS X applications with the tcl event loop running transparently as part of the CoreFoundation event loop. The talk will explore the internals of the new notifier, detail how to setup the embedded notifier and the caveats to be aware of. It will conclude with a demonstration of Tcl embedded in a Mac OS X Cocoa application.

Arjen MARKUS (Deltares, Netherlands)

Keywords: Tcl, hydrodynamics, dike, flood, Linux, Cluster, statistics

Download presentation and article: (540K), article (doc, 490K)

The safety of (river) dikes in the Netherlands, located in the delta of the rivers Rhine, Meuse and Scheldt, has been the subject of debate for more than ten years. Most methods to estimate the required dike height, as part of the risk assessment focus on the river only. If, however, a river dike breaks somewhere along the river, this influences the chance of dike breaches elsewhere: the water level downstream may be lowered, but the water can now reach the dikes around the flooded area from the inland side. This effect is known as river system behaviour.

To understand the importance of this effect and the possible consequences it has on the design methodology, we studied the hydrodynamics of a part of the Netherlands that is enclosed by the Rhine and Meuse. A major part of that study was to conduct several hundreds of simulations with different dike strength parameters and model flood wave to enable a statistical analysis of the risks in this area, vis-a-vis casualties and economic damage if a dike breaks.

This involved getting a set of otherwise independent programs to work together: the dike strength and flood parameters were selected via a Monte Carlo method, this led to input for a detailed hydrodynamic model of the rivers and the surrounding area and results from that model were analysed to estimate casualties and economic damage.

As these programs ran on different types of computers in different locations, Tcl programs were developed to automate the transfer of the input and output, the scheduling of the programs on the Linux cluster and local PCs and the checking of the computations. Furthermore, Tcl programs facilitated in collecting the results in a condensed form, useful for the subsequent statistical analysis.

While the framework as such was set up in an ad hoc manner, there is an elegant underlying formal model: the tuplespace that describes this framework very well. The file system of the Linux cluster served as the database system and Tcl's abilities to interact with the OS and the file system (both on Linux and PC) were instrumental in managing the actual computations.

Delft Hydraulics, GeoDelft, the Subsurface and Groundwater unit of TNO and parts of Rijkswaterstaat have joined forces in a new independent institute for delta technology, Deltares. Deltares combines knowledge and experience in the field of water, soil and the subsurface. We provide innovative solutions to make living in deltas, coastal areas and river basins safe, clean and sustainable.

Adrien PEULVAST, Eric BOUDAILLIER (AnsaldoSTS, France)

Keywords: Tcl, railway, simulation, maintenance

Download presentation: (1100K)

Ansaldo STS (Railway Signalling Company) feedback and experiences on several projects in France and abroad show that it is difficult to capitalize signalling applications from one customer to another due to the Railways country histories : SNCF(France), DB(Germany), MOR(China), NR(UK)...

According to these different domains knowledges a high flexibility is required to develop successfully signalling applications. This can be obtained through adaptable and easy to use development tools.

This is why we used Tcl/Tk in our simulation tools, and by extension in our maintenance tools.

The presentation will show the company's graphical tools and usage on different projects and some demos in the railway signalling domain.

Axel NAGELSCHMIDT (Biotronik GmbH & Co KG, Germany)

Keywords: Tcl, application development, beginners style, introspection, lessons learned, libraries, incrTcl, snit, GUI, templates

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The talk shows some experiences gained in 12 years of Tcl programming. Starting with a real life example of a simple editor, various ways of extending and supporting applications are presented. Different efforts using namespaces and the OO frameworks incrTcl and Snit are presented and compared.

Marc HOFFMANN (Hoffmann RD, Netherlands)

Keywords: Tcl, web, cgi, wiki

Download presentation: (90K)

TWD is a simple environment for the development of tcl based web applications. TWD is inspired by T's wiki, which in turn is an adaption of Tiddlywiki.

The goal of TWD is to provide tcl programmers with an easy to understand and simple to use environment to build web applications. TWD is not developed as an high performance web environment like AOLserver, nor is it developed as an end user application like wordpress. The primary goal is to allow a tcl programmer to build web applications based on url dispatch and query parameters. For this TWD supplies a session module, a user module, and a general dispatch framework. TWD is currently in alpha development and is based on cgi, although fcgi/scgi and are also considered. The primary application currently working is T's wiki, a wiki heavily based on javascript.

Jos DECOSTER (Private, Belgium)

Keywords: Tcl, Wub, web application framework

Download presentation and examples: (740K), Examples (.zip, 760K)

Since the Great Wiki Meltdown in the spring of 2007, the Tcler's Wiki has been running on Wub. Written by Colin McCormack, Wub is a pure Tcl Http 1.1 webserver, a successor of TclHttpd. It makes heavy use of bleeding edge Tcl (8.6) features such as dicts, co-routines, zlib and TclOO. Wub comes with a lot of what it calls Domains: pluggable building blocks adding new functionality.

This talk will not focus on the inner workings of Wub, but will take a step-by-step approach on runnig Wub and using its domains to make Web applications.

Topics covered:
- Getting Wub
- Runtime requirements
- Running Wub out-of-the-box
- Configuring your web application with Nubs: domain, rewrite, redirect
- Using the File'domain
- Templating with the Mason' domain
- Mapping URL's to Tcl commands using the 'Direct' domain
- The Wub API - Adding JQuery' to your Web application with the jQ' domain
- Init parameters
- More Nubs' (block, literal, code) and interactive introspection
- Using the Convert domain for content transformation
- Advanced Domains:
. Tub: a generic repository for form values
. Tie: web interface on namespaces
. Coco: mapping co-routines to URL's
. Honeypot: catch bad spiders
. Repo: a file repository
. stx: a wiki-inspired format to specify html documents
. Icons : a set of icons
. Session: session management
. CGI, Rest, Sinorca, Simplicio
- Utilities:
. Cookies
. Report
. Query
. Introspection

Alexios ZAVRAS (Independant IT Consultant, Greece)

Keywords: Tcl, GUI, file manager, RESTful web service, massive deployment

Download example: Example (.zip, 2K)

GRNET, the Greek Education and Research Network, decided in 2008 to offer online storage services for all faculty, students and researchers in Greece. All users would have access to virtual online disk, with enhanced functionality such as:
- sharing data with list of friends
- keeping of versions of files
- automatic backup of local data.

The initial spec called only for a Web-based client interface; however a desktop client was soon also commissioned. The talk will present this client, which was built purely in Tcl with a handful of extensions. The communication with the server makes use of a RESTful web service API. The client is essentially a file management GUI application, with special functionality for the online storage content. Since it was written with appropriate abstractions on the file level, it could be used in other cases as well.

Axel NAGELSCHMIDT (Biotronik GmbH & Co KG, Germany)

Keywords: Tcl, application in a database, SQLite, RPC, client-server, bot, application deployment, update server

Download presentation: (150K)

Complementing the talk about application development, an example of an application server written in Tcl is presented. In contrast to using the various presented solutions (tclkit, starkit, freewrap) this server uses the SQLite database extension to hold the database, application data and configuration settings. Different methods of application deployment and update distribution are presented.