Buyer's FAQ

Updated March 2024

This page answers some typical questions from potential purchasers of Winteracter, the Fortran GUI toolset.

Note: This is not a technical FAQ. Winteracter includes an extensive technical FAQ in its documentation. See the Support page.)

Fundamental Product Features

  • Does Winteracter support true Windows look & feel?

Winteracter uses the native menu/window/dialog handling features provided by the Windows API to ensure a 'standard' look & feel. The X Windows version uses Xlib and the well established Motif interface, to achieve a close equivalent.

  • Are visual tools supplied or is it just a subroutine library?

From Winteracter's inception we were committed to providing visual tools to simplify the design and development process. One of Winteracter's core tools is the resource editor, which is used to create and mantain your application's menus, dialogs, toolbars, icons, bitmap-buttons and cursors. This allows you to design and edit your main user interface components without writing a single line of code. You also get full control over the layout of your dialogs, instead of having to second guess complex auto-layout algorithms.

Graphs can also be designed visually, using GraphEd. This uses a dual window interface which show both the graph's expected layout and the source code required to generate it. Graph layouts can be saved as data files, allowing repeated reuse.

Winteracter also includes its own development environment (WiDE), which integrates the design, edit, compile, link, run, debug cycle. While use of WiDE is optional, it offers a credible alternative to compiler/platform-specific IDEs from other sources.

Our commitment to a visual style of programming is on-going. The Winteracter visual toolset is regularly updated and expanded. Significantly, virtually all of these tools are supplied on all supported platforms, not just on Windows. The full set of Winteracter tools are detailed on the Visual Tools page.

  • Is a Fortran compiler included?

No. You should choose and obtain a compatible Fortran compiler yourself. See Supported Compilers/Platforms for the current list.

On Windows, we have versions of GCC available for download, which have been packaged with an installer which can automatically configure WiDE ready to use it. These downloads include the GNU gfortran compiler.

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  • Are there any hidden costs like royalties or at-cost extras?

There are no run-time fees or royalty payments. The licence agreement specifically permits redistribution of Winteracter-based programs, without any royalty requirement. Educational licence holders are restricted to redistribution to other educational/research users. There are no such restrictions on Commerical licence holders.

Winteracter includes all visual tools and hardcopy export drivers as standard. Unlike some competing products, it is not necessary to purchase a selection of "optional" components to obtain a full toolset. You just need one of the supported Fortran compilers.

Note : If you intend to build help files in Microsoft's HTML Help (CHM) format, via the Windows version of our HelpEd tool, you will need the corresponding Microsoft help compiler HHC, which forms part of the HTML Help Workshop. This is freely downloadable from Microsoft's web site.

  • Can I install on more than one computer?

The Winteracter licence agreement allows the software to be installed on two computers, provided it is not used on both computers at the same time. In other words, it is a single user licence which allows installation on two computers used by that licensee.

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  • What are resources and how do they work?

Winteracter makes use of resource files which define dialog and menu layout. In addition they can contain other UI resources such as bitmaps, metafiles, icons and cursors. This resource gets incorporated into your executable just like any other object file, using the resource compiler which is supplied with your compiler tools (under Windows) or with Winteracter itself (Linux/Mac). The individual resources are then accessible in the calling Fortran program via simple numeric identifiers.

The resource file and the associated list of numeric identifiers are maintained automatically by Winteracter's resource editor. Developers need no knowledge of the resource script format.

  • What are the benefits of a resource based programming model?

Our resource based programming model is the key to our powerful visual design methodology. It clearly separates dialog/menu design from input handling. Good UI design is a development task, not something to be performed at run-time. A resource based programming model makes this possible. What's more, changes to menu and dialog layout can be made and viewed in our resource editor and saved as updated resource files with no need for Fortran source recompilation.

"But I've read that resources run out very quickly. Won't Winteracter programs use up all my Windows resources?" Certainly not! This fails to understand how resources work. For example, under Windows, the resources built into an executable don't use any of the memory reserved by Windows for resource usage until explicitly requested. Winteracter allows you to load and unload dialogs, etc as needed. It's up to you how many dialogs you load simultaneously. In reality, a Winteracter program uses no more system resources than development systems which use 'on-the-fly' resource creation.

Another benefit of using resource files to define your user interface layout, rather than subroutine calls, is the ability of our resource editor to reload and edit those layouts throughout the development cycle. Visual tools which generate Fortran source code to define the user interface cannot do this.

  • Where do I get a resource compiler?

You will have one already! On Windows, your compiler tools will include a resource compiler. On Linux and Mac, X/Winteracter includes our own equivalent.

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Language / Calling Interface

  • Is Winteracter totally Fortran based?

Our business has always been about servicing the needs of Fortran programmers writing Fortran programs. Winteracter delivers just that : A totally Fortran-based GUI solution. No mixed language programming is necessary, avoiding all the horrors of interfacing to C, C++, Delphi, Visual Basic or Java. Our aim is one language, one solution.

  • Why Fortran 9x/200x?

From the very beginning, Winteracter was conceived as a "modern Fortran" product and the decision was made to move on from Fortran 77 (as supported by our earlier INTERACTER product). Hence, it relies on compilers which support Fortran 90 (or later), allowing it to take advantage of features such as modules, free format source code, optional arguments, CASE constructs and so on. The WINTERACTER module in particular is a fundamental part of Winteracter programming, providing a full set of interface definitions (eliminating most argument passing errors) and meaningful parameter names. An extensive set of Fortran Winteracter example programs are also provided, which all use modern Fortran syntax.

Of course, simply because Winteracter requires a Fortran 9x/200x compiler, this does not mean you cannot reuse your old Fortran 77 code. Newer Fortran standards include the whole of Fortran 77 as a subset.

  • How readable is Winteracter code?

If you care about the readability and maintainability of your code, Winteracter must be high on your list. We believe our calling interface is simpler and cleaner than any competing Fortran based product. Winteracter uses meaningful names for all of its subroutines, instead of cryptic 6 character names. In addition, hundreds of meaningful parameter names are declared for subroutine argument values and function result codes. You can actually read a typical Winteracter program and get a pretty good idea of what's going on, without having used the product or written the program.

  • Does Winteracter require the use of callbacks?

No it doesn't. Callbacks make program flow hard to follow. Instead we have implemented what we term 'semi modeless' dialogs. These appear modal to the user (i.e. the rest of the application is blocked out) but modeless to the application (i.e. the program retains full control over the user interface while the dialog is visible). Winteracter can also report when dialog fields change or when the focus moves between fields, allowing field-by-field validation without resorting to callback routines.

  • Can I use Winteracter with other GUI development tools?

While developers may find that certain Winteracter features work with some 3rd party GUI tools or APIs, we are unable to provide advice or support on the use of these programming interfaces. We don't have any control over their behaviour. They may well perform message/event processing which interferes with Winteracter's normal operation. The use of such tools is therefore likely to be counter-productive.

  • Can I use Winteracter with other libraries?

In general, assuming those libraries are not GUI-related, then yes. Winteracter neither "allows" nor "disallows" use of third-party libraries, such as IMSL, NAG, MKL etc. In effect, it is neutral to their use and imposes no restrictions on which can or cannot be used.

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  • Does Winteracter offer more than basic graphics primitives?

Winteracter's extensive graphics routines are derived from our well established INTERACTER product. This means that Winteracter's graphics are extensively tried and tested. It also means that they have been developed to a level of maturity way beyond just a few GDI line and fill interface routines. In addition to comprehensive device independent primitives, we also provide extensive higher level graph/chart plotting and 3D modelling functions at no extra charge. A visual graph designer is also provided, which can be used to generate tailored Fortran source code for each of the supported plot types.

  • Which hardcopy/export formats does Winteracter support?

Fortran graphics programmers invariably need to get their results onto paper or into third party products like word-processors. As an industry we've managed to invent more ways of doing this than bears thinking about. Thankfully, I.S.S. has been addressing this problem since the late 1980's, so Winteracter not only supports Windows API output to Print Manager and Windows metafiles, it also provides drivers for HP-GL, HP-GL/2, HP PCL, Epson ESC P and ESC P/2, PostScript, EPS, DXF, CGM, SVG, BMP, PCX, PNG and JPEG/JFIF formats. Bit image printer dumps are also supported. This way, whatever device you need to print on or whatever package you need to export to, chances are we provide a solution which genuinely works. Also, remember that you get all these drivers as standard with Winteracter.

Also, the supplied 3D modelling subroutines can import and export model descriptions in DXF, STL or OBJ formats.

  • Does Winteracter support the old CalComp interface?

Winteracter includes a full emulation of the old CalComp HCBS interface (1977 spec), supplied in both source and compiled form. Also included is an emulation of Lahey's Video Graphics Library (LVGL) as supplied with F77L, F77L-EM/32 and early versions of LF90. As an added bonus the emulation also supports a substantial subset of Lahey's former add-on Graphoria product. Both the LVGL and Graphoria emulations are also supplied in source and compiled form.

  • Are web browser graphics formats supported?

We support PNG (Portable Network Graphics), JPEG and SVG (Scalable Vector Graphics - the web vector graphics format defined by W3C).

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Supported Platforms

  • What version do I need for 64-bit Windows?

The Windows version includes support for creation of 32-bit and 64-bit applications on both 32-bit and 64-bit Windows. Simply order the Windows version, whatever your requirements on that particular platform.

  • Is a Linux version available?

Yes. The Linux version is based on X Windows and the Motif toolkit. Known as X/Winteracter, this version provides a high degree of compatibility with the Windows implementation. Programs can be developed on and for 64-bit Linux/x86_64. (32-bit Linux support was dropped at v14.0.)

  • Is a Mac version available?

The X Windows version is available for Intel-based Macs. This relies on the "XQuartz" X server, which is downloadable from the XQuartz web site. A Mac version of the Motif toolkit is also required, as on Linux. Suitable versions of Open Motif are downloadable from our Open Motif page.

As on Linux, programs can be developed on and for 64-bit Intel based Macs. 32-bit Mac support was dropped at v14.0 and support for the old PowerPC platform ceased in 2006 at v7.10a.

  • Are versions available for non-Intel platforms?

Currently, all implementations target Intel/AMD based platforms.

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Lahey Fortran compilers

  • Which Lahey compilers does Winteracter support?

On Windows, versions 5.7 or later of Lahey/Fujitsu Fortran (LF95) are supported. This includes support for the version of LF95 which was supplied with Lahey Fortran 7.x. Any of the Express, Standard or Pro variants of LF95 are suitable. Since LF95 is 32-bit, the corresponding version of Winteracter can be used to create 32-bit applications.

The Windows version of Winteracter also includes support for Lahey/GNU Fortran ("LGF"). This implementation allows creation of both 32-bit and 64-bit applications. (Note: LGF was available both as a standalone product or as part of Lahey Fortran 7.5 onwards. Winteracter supports both.)

The long-discontinued Lahey "Fortran" for .NET compiler was never supported for several reasons, primarily because it did not compile standard Fortran. Support for the obsolete LF90 and Elf90 compilers was dropped at v11.0, as was support for the early versions of LF95 (5.0-5.6) which relied on the old Phar Lap tools. Support for the old Lahey Linux compilers has also been dropped (32-bit @ v14.0 and 64-bit @ v15.0).

Despite the closure of Lahey, we are still supporting LF95 and LGF, for the foreseeable future. If you are still using one of the Lahey compilers on Windows, then you can continue to do so with the current Winteracter release. You will only need to change, next time you need to reinstall your compiler(s) (e.g. when setting up a new PC). Lahey's licence activation will no longer work, following the closure of Lahey and their Tallac sales offshoot.

  • What is the difference between WiSK and Winteracter?

The Lahey Winteracter Starter Kit (WiSK) (as supplied with various Lahey Fortran products from v4.0 onwards) included plenty of functionality allowing creation of substantial Windows programs. However, if you decide that you want access to more user-interface or graphics features or your Lahey compiler is no longer installable, then you should consider upgrading to the the full version of Winteracter.

The full version of Winteracter adds memory bitmap/metafile/icon manipulation, toolbars/tooltips, tabbed dialogs, more dialog field types, grid ("spreadsheet") input, built-in editor, Print Manager hardcopy interface, a more extensive range of graphics primitives, presentation graphics, 3D modelling, several graphics hardcopy/export drivers, more visual tools, operating system interface, etc.

  • Is Winteracter compatible with Lahey's Elf90?

Versions up to 10.10 supported this compiler, but Elf90's extreme age and restricted functionality meant support was dropped at Winteracter 11.0.

  • Which versions of Lahey/Fujitsu Fortran are supported?

All but the earliest Windows versions of Lahey/Fujitsu Fortran 95 are supported:

  • On Windows, any Lahey Fortran compiler package which included Lahey/Fujitsu Fortran 95 (LF95) 5.7 or later is supported, i.e. any of LF95 5.7 or Lahey Fortran 7.0-7.9. The earliest versions of LF95 (5.0-5.6) which relied on the old Phar Lap linker are no longer supported, as of v11.0.
  • Lahey Fortran v7.x existed in a variety of configurations, combining multiple compilers in various permutations. The Win32 Fortran 95 compiler which shipped previously as LF95 5.7, has subsequently formed part of Lahey Fortran v7.x "Enterprise" and "Professional" editions. It continued to ship with Lahey Fortran versions right through to the final LF7.9 release. LF 7.5-7.9 combined Lahey/Fujitsu Fortran and Lahey/GNU Fortran. Since the version of Lahey/Fujitsu Fortran (LF95) which shipped as part of LF 7.x remained essentially unchanged from v5.7, Lahey/Fujitsu Fortran support added at Winteracter 4.10 remains equally applicable to the v7.x releases. Support for Lahey/GNU Fortran was first added to Winteracter at v9.30.
  • Lahey Fortran for Linux (32-bit and 64-bit) is no longer supported, as the compilers were discontinued some time ago and won't run on recent Linux versions.

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Visual Fortran

  • Is Visual Fortran supported?

Winteracter supports Intel Visual Fortran 11.0 or later. This is the same compiler which shipped under a variety of Intel product names, such as "Composer XE" or "Parallel Studio XE". Both 32-bit and 64-bit versions are provided for use with this compiler, on Windows. More recently, the compiler has been rebranded as "Intel Fortran Compiler Classic", part of the Intel oneAPI HPC Toolkit. The Windows version of Winteracter for use with Intel compilers is suitable for use with both the "Visual Fortran" and "Classic" compilers (they are essentially the same compiler).

As of Winteracter v15.0, the new "Intel Fortran Compiler" (also known as "ifx") is also supported, allowing creation of 64-bit programs on Windows and Linux. Note: This is no longer referred to as "Visual Fortran" and relies on different underlying compiler technology.

The earlier Digital/Compaq Visual Fortran 5.0/6.x compilers were supported for 20 years, but support for these long-obsolete compilers was eventually dropped at Winteracter v11.0.

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Open Source and Free Compilers

  • Are open source compilers supported?

Every Winteracter licence, on all platforms, includes support for GNU gfortran. On Windows, the MinGW implementation is supported, allowing creation of both 32-bit and 64-bit applications. On Linux and Mac platforms, 64-bit GNU gfortran is supported.

Support for the g95 and Open64 compilers was dropped at v11.0, since neither have been updated in several years. Linux and Mac gfortran implementations were introduced at v11.0 as replacements, since gfortran remains under active development.

  • Are free-of-charge commercial compilers supported?

Winteracter is compatible with the following free-of-charge commercial compilers:

  • Intel : All of the Windows, Linux and Mac versions include support for the Intel Fortran Compiler Classic ("ifort"), which forms part of the freely available Intel oneAPI HPC Toolkit. The 64-bit Windows and Linux versions are also compatible with "ifx", Intel's newer LLVM-based compiler. The Mac version of X/Winteracter continues to support ifort, despite Intel's withdrawl of support for the Apple platform at oneAPI 2024.
  • NVIDIA : The Linux version includes 64-bit support for NVIDIA Fortran, which forms part of the freely available NVIDIA HPC SDK. A Windows version may be made available, if NVIDIA ever deliver on their promise to release the compiler for that platform.
  • Silverfrost : FTN95 Personal Edition can be used with the Windows version to create 32-bit applications. However, this compiler is restricted to personal and evaluation use.

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Support and Updates

  • What about technical support?

We operate a Winteracter technical support service via email. Registered users may submit bug reports and other Winteracter related enquiries to this service. See the Support page for more detailed support instructions.

  • When is the next new release due?

Periodically, we introduce new versions adding new functionality. We do not pre-announce new release dates. Availability of new versions is always announced on this web site, on the day of release.

  • What is your upgrade policy?

Users of any previous Winteracter release can purchase an upgrade to the current version. The cost of an upgrade is related to the age of your existing version. Broadly, the newer your licence, the cheaper the upgrade. (Note: We no longer offer maintenance contracts. These were dropped in 2001.)

Customers who purchase a new licence or upgrade immediately prior to a new release will normally be entitled to a free upgrade to the new version. Qualification for free upgrades is based on the date of shipment from I.S.S. or a recognised I.S.S. reseller and in any event is at the sole discretion of I.S.S. Ltd. Free updates are normally shipped automatically and do not need to be requested.

  • Can I upgrade from a 32-bit licence to 64-bit?

Yes. All licences now include 64-bit support. Holders of earlier "single-target" 32-bit licences can upgrade to the current version. Upgrade fees are as per our Price List.

  • How are bug fixes provided?

Between new releases, we periodically make minor updates available. These fix known issues in the current release and are signified by a revision letter (e.g. the first update after the initial release of version 16.0 would be v16.0a). Updates are specific to a particular release (e.g. to install a 16.0a update you must own a v16.0 licence).

We do not have a fixed update schedule. Frequency depends largely on the number and severity of fixes which have accumulated. Several updates are usually uploaded to our web site between new releases. Updates for a particular version number stop when the next new release becomes available. Updates for earlier versions normally remain available on our web site for several years.

As of v15.0, a "Check for update" button is provided in the "Licence information" dialog, which is accessible via any of WiDE (on the Help menu), the Windows Start menu, the desktop shortcuts or the launchpad.

Updates for old versions, prior to 10.0 are available from the Updates page on this site. From v10.0 onwards, updates are provided via whole product downloads, from the page specified in your licence email.

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INTERACTER Compatibility

  • Why did you develop a new product?

The primary motivation was the 'look and feel' issue. Many customers were demanding a truly Windows-like appearance. We also encountered demand for similar functionality on other platforms under X Windows (particularly on Linux). Portability and backwards compatibility issues precluded such a development within INTERACTER, which employed a character mode interface, even on graphics displays. Instead, we decided to take all those parts of INTERACTER which could be reused (notably our tried & trusted graphics and operating system interface) and incorporate them in a new product. The user interface elements of Winteracter (menus, dialogs, etc.) were therefore redesigned to match the structure of the Windows environment while retaining much of the simplicity and style of programming interface which made INTERACTER popular.

  • What happened to INTERACTER?

INTERACTER development ceased in 2000 and technical support stopped in 2006. INTERACTER is no longer available. Winteracter is recommended for new development.

  • How do I convert my INTERACTER programs to Winteracter?

Any INTERACTER graphics code can be used virtually without modification. The only change likely to be required is the introduction of a USE WINTERACTER statement at the start of each program unit which calls our graphics routines. Similarly code which calls routines in our OS (operating system), BF (Binary File handling), CH (character handling) and MM (max/min) subroutine groups can also be reused.

Code which uses INTERACTER's Forms Manager will require modification, notably the conversion of forms to Windows dialogs. However, a tool called IFD2DLG is provided which will do this automatically. Many of INTERACTER's Forms Manager routines have direct equivalents in Winteracter too, notably the field assignment/retrieval routines. The function of the INTERACTER form designer INTFORM is replaced by the dialog editor, which forms part of the resource editor. Other code which relies on INTERACTER will generally require reimplementation. The documentation supplied with Winteracter provides more detailed advice on how to achieve this.

Since Winteracter's calling interfaces have steadily evolved over the intervening years, old INTERACTER based sources may benefit from analysis by the supplied Obsolete Feature Checker.

  • Can I still use the old INTERACTER short name interface?

INTERACTER was upgraded to use a modern long-name calling interface in 1994, at v3.0. Legacy codes which still use the early 6-name calling interface can be upgraded using the TOLONG command line tool, which shipped with INTERACTER from v3.0 onwards. TOLONG is also included with Winteracter.

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