CroPL Frequently Asked Questions (FAQ)

Here is a bunch of information about CroPL, in question-and-answer format:

Sometimes you call it "CroPL", sometimes "CroPL II". What's up?

The CroPL application framework is many years old (the roots of it were originally written in Macintosh Pascal!) In 2005, we began a major rewrite to create "CroPL II", the next-generation framework. At this point, CroPL II is more or less complete, and we don't use "classic" CroPL for anything other than pre-2.0 versions of Wormhole, so the names have become interchangable again: "CroPL" means "CroPL II", and we'll call it "Classic CroPL" if we need to refer to the old one for some reason.

What does the name "CroPL" mean?

It stands for "Cross-Platform Library." Don't laugh, my competition has names like "CPLAT," "Qt," and "YAAF." "CroPL" practically rolls off the tongue in comparison.

How much does it cost?

See the license agreement for the complete answer. The short answer is: it depends on what you're going to do with it. If you make freeware for personal or consumer use, it's free. If you're making shareware, it's $100 or a free copy of your product(s). For pretty much everybody else, it's 8 percent of what you make on the derivative products. All of these prices are the "general answer;" you can negotiate with me if you think they're unfair, shouldn't apply to you, or you have some weird case that doesn't fit any of these models.

Why would any shareware developer pay $100 rather than a free copy?

I've been told there are business/legal reasons why it's sometimes desirable to pay cash for things rather than pay in product. I don't know what these reasons are, but I'd hate for them to be a stumbling block for someone who wanted to use CroPL.

What platforms does CroPL II generate code for?

Assuming your compiler is capable of it: Mac OS 10.3 (Jaguar) and newer (PPC and Intel), Windows 98 Second Edition, Windows ME, Windows 2000, Windows 2003 Server, and Windows XP.

Support for 98SE and ME is much harder than 2000 & XP - you need to mess around with redistributable libraries from Microsoft, and learn some of the vagaries of linking Unicows and gdiplus.lib. It's fragile, and getting it to work is tricky. So for the casual user, assume Windows support is 2000, 2003, and XP.

On the Mac side, Apple's APIs (even the supposedly cross-OS Carbon ones) have changed dramatically over the life of OS 8, 9, X, and even during the various versions of OS X. A huge number of interfaces were added in OS X 10.3, and there are a number of bug fixes in 10.3 as well, upon which many of CroPL's features depend. So we don't support OS X versions older than 10.3. (If you're writing only to OpenGL, you can go back to 10.1 successfully). Intel Binaries are only available in 10.4, of course (that's the oldest version Apple supports).

Note: My development systems always run the latest OSes, since that's where compatibility issues tend to arise. I rely on brief test runs and outside testers to find bugs in the non-current systems (98SE, ME, 2K, Mac OS X 10.3). If you find a platform-specific bug, in these OSes, please let me know immediately (platform compatibility bugs take very high priority for me.)

CroPL always attempts to use the most general solution when faced with platform-specific APIs, so it's been almost immune to "It works on Win2k, but not Win98" sorts of bugs. There have been two that I can remember, over the entire history of CroPL. Which is reassuring, if not an actual guarantee of future compatibility.

Why not Linux/Unix?

I'd love to. I just haven't had the time. Bringing CroPL up on a new platform would take a 3-4 full-time months of effort, and I just don't have that kind of time. Maybe someday. Curious browsers of the code will notice that there's a "UT_PLATFORM_LINUX" define in UtUniversalHeaders.h. I've been playing around with this; thus far it's just an experimental effort, though.

What compilers does CroPL II work with?

The "Recommended Compilers" are:

[Windows] Visual C++.NET 2005 or 2008. You can use the free command-line tools if you can figure out how to get the Makefile thingy set up. CroPL II doesn't actually use .NET functionality, it talks to the underlying Win32 SDK.

[Macintosh] Apple's XCode 3.0. CroPL is primarily a Cocoa application, although it uses some non-Cocoa functionality as well. These tools are free from Apple.

Because CroPL II compiles in GCC on the Mac, you can probably use the GCC compilers on Windows, as well. I haven't tried this. I have done some experimenting with the GCC compilers on Linux, but that's unsupported.

Is CroPL Open Source?

Not if you insist on capitalizing it like that. CroPL is provided as source code (at least), but it's commercial software, and I place a lot of limitations on your ability to pass it on. That's "open source" in the old meaning of the words. In the last several years (well, decades), several groups have commandeered the term "Open Source" to mean compliance with various licenses on distribution, usually involving your giving away the code and the rights for the recipients to give it away, too. CroPL is not compatible with any "Open Source" license that I'm aware of.

What's to stop me from using your source code without license?

Your honesty. Failing that, my lawyers. Even downloading the source indicates compliance with the license. The license is meant to be non-onerous (if you're not making anything off your software, it's usually free. If you are making money, it's not very expensive, compared to most development tools.) I want CroPL and it's subsidiary products to generate my full livelihood someday. You want that, too -- it means I'll be able to spend a lot more time at it, which will produce new features faster.

Is CroPL ShareWare?

No. You must agree to the license agreement BEFORE evaluating CroPL, and the license agreement gives you no flexibility about when to and whether to pay for it. Except for these caveats, CroPL's license is fairly similar to shareware, in the sense that you can evaluate the software without financial risk.

I'm not a strong believer in the shareware model; I'm cynical enough about human nature and human self-deception ability to believe that when people are given flexibility in when to pay, it gets put off...indefinitely. Unfortunately, the few experiments I've seen done on this issue tend to support that cynical view: "crippleware" programs, for example, are registered at a rate considerably higher than pure shareware ones. (I'm defining shareware in the classical sense, of full-featured programs with a "when ready" payment scheme. Such payment is not intended by the author to be "optional," but it's often seen that way by the end users.) This is partly why classical shareware is disappearing as a business model; most software these days is either commercial, crippled demos, or free.

So why do you cut shareware authors a break in the license agreement?

Because their cause is noble. I believe it's hopeless, but I've been wrong before.

Is CroPL a free program?

No. Not free as in beer, not free as in freedom, not free in any other sense. It's bound by license agreement. Depending on your use, you may not have to pay for it, but that doesn't give you any rights to the code beyond those granted by the license agreement.

So why do you cut free software authors a break in the license agreement?

Hmm. Depends on your definition of "free." The license agreement defines it as 'costing the end user nothing.' (As opposed to "free" as defined by organizations like the FSF, which make it a much more political statement.) I would like to see CroPL widely adopted, because the greater my user base the better my chances of people knowing about it and using it for paying programs. A cost that cannot be recouped is a barrier to people using the software. They're not taking advantage of me for financial gain; their cause is even more noble (and from a profitability standpoint, more hopeless) than that of the shareware authors.

Why do you give out source at all, then?

Take your pick:

• Because I, or my company, might not be here tomorrow, and people will have code that depends on it.
• Because CroPL is always a work in progress, and people need to be able to determine if a program abnormality is their bug, or mine, of if I've failed to implement something I should.
• Because one of CroPL's target markets is new, hobbyist programmers, who might like to see how things are done. (And occasionally, how they shouldn't have been done.)
• Because people occasionally consider this an invitation to fix my bugs for me, which makes the software better for all of us.
• Because code is inherently more portable than binaries and libraries.
• Because I can never please everybody, and there will always be those that will want to rip out some of my code and replace it with their custom stuff. I don't endorse this: it makes future maintenance of your program a real nusciance, and it's often not necessary in OOP, but I don't kid myself that it won't happen.

Didn't answer your question? Try the generic CrystalFire Software FAQ here instead.