# Togl — a Tk OpenGL widget

### Copyright © 1996-2009 Brian Paul, Ben Bederson, and Greg Couch

## Index

- Introduction
- Download/Installation
- Using the togl widget
  - Tcl API
  - C API
  - Upgrading to version 2
- Frequently Asked Questions (FAQ)
- Mailing List
- Reporting Bugs
- Contributors

## Introduction

Togl is a Tk widget for OpenGL rendering. Togl was originally based on OGLTK, written by Benjamin Bederson at the University of New Mexico. Togl's main features are:

- unifies Microsoft Windows, X11 (Linux/IRIX/...), and Mac OS X Aqua support
- support for requesting stencil, accumulation, alpha buffers, etc.
- multiple OpenGL drawing windows
- simple stereo rendering support
- simple, portable font support
- color-index mode support including color allocation functions
- overlay plane support
- OpenGL extension testing from Tcl
- Tcl Extension Architecture (TEA) 3 compliant

Togl does almost no OpenGL drawing itself, instead it manages OpenGL drawing by calling various Tcl commands (a.k.a., callback functions). Those commands can be C functions that call OpenGL (in)directly or another Tcl package (e.g., Tcl3D).

Togl is copyrighted by Brian Paul (brian_e_paulATyahooDOTcom), Benjamin Bederson (bedersonATcsDOTumdDOTedu), and Greg Couch (gregcouchATusersDOTsourceforgeDOTnet). See the LICENSE file for details.

The Togl project and home page are hosted by SourceForge.

## Mailing list

See the Togl project at SourceForge for mailing list information.

## Reporting Bugs

There is a bug database on the Togl Project Page. You may also discuss bugs on the mailing list.

It may be worth upgrading your graphics driver and retesting before reporting a bug, as, historically, many Togl "bugs" have been fixed by a graphics driver upgrade, especially on Microsoft Windows.

When reporting bugs please provide as much information as possible. Such as the version of Togl, which operating system (e,g., Microsoft Windows, Red Hat Linux, Mac OS X, etc.), the version of the operating system, and the version of the graphics driver. Also, it's very helpful to us if you can provide an example program which demonstrates the problem.

## Contributors

Several people have contributed new features to Togl. Among them are:

- Ramon Ramsan — overlay plane support
- Miguel A. De Riera Pasenau — more overlay functions, X11 functions and EPS output
- Peter Dern and Elmar Gerwalin — Togl_TimerFunc and related code
- Robert Casto — Microsoft Windows NT port
- Geza Groma — Microsoft Windows 95/NT patches
- Ben Evans — SGI stereo support
- Paul Thiessen — Macintosh support
- Jonas Beskow — Tcl/Tk stubs support
- Paul Kienzle — TEA debugging and patches
- Greg Couch — version 1.7, 2.0, 2.1

Many others have contributed bug fixes. Thanks for your contributions!

Last edited on 4 February 2009 by Greg Couch.