My co-developer hates me from using other open source code modified

Hi guys, I thought of posting here for more opinions because my co-developer and I have different opinions when it gets to using others open source code.

We are developers of an open source (GPL) screenshot capturing program called ZS and at the moment we are developing its successor called SX.
I wanted to add “annotate after capturing image” support with SX. With ZS in the past I also did this by slightly modifying an image editor called GSE which was part of another screenshot capturing program called GS. I thought that was best suited for my needs because out of all the other image editors out there, it was the easiest to use for quick obfuscation of sensitive areas of the screenshot and I could highlight the way I liked it too. Loading the image editor was much quicker than MS Paint or Paint.net so I successfully integrated GSE to ZS. I did not change any program titles or anything; I used them as it is and also acknowledged them in the About Window. My primary goal was to get useability perfect.

Jaex, my co-developer did not like what I did with GSE and ZS but his influence was minimal at the time with ZS because he joined later to the ZS project. Since then has significantly contributed to the projects, also made another screenshot program from scratch called ZU and now has a much larger influence. He would hate it if I do that again for SX.

He would suggest me to use Paint to annotate.

He would tell me:
highlight : http://i.imgur.com/yOGxV.png
black background: obfuscate

I told him, I don’t like to use a black background to obfuscate and the effect I want to have is http://i.imgur.com/yKnD6.png
I told him, I am a developer so I would not any time compromise myself to be forced to use something that does not fully suit my needs. For average user who depends on what’s available there is no choice. But I am not that average user; if I have the choice to mod something to work something out to suit my needs why would be stuck with less optimal solutions?

In a summary these are his opinions:

He doesn’t want to use GSE with SX because he believes it is theft. It is extremely unprofessional too he says. If I wanted annotating so much, I should be making my own. He says GSE never used other people’s libraries and wrote everything themselves. He asks me why would we advertise their app name in our app. He suggests me to take screenshots that does not require obfuscating by taking different potions of the screen.
He distinguishes this from using libraries such as SSHNET.dll because they are coded purely for reuse. He finds no problems with that – I understand totally.

So basically what he cannot stand is modifying other open source code that was not meant purely for reuse because he thinks it is unprofessional.

My arguments are, we are not doing anything commercial, our application is open source too and I provide acknowledgement; I have no competition in mind. I am mainly focused on usability and I would just reuse anything that makes my life easier to have the best outcome.

Looks like I have to have a SXmod so that I can use GSE as the image annotator because why on earth I have to compromise how I do thinks when I have the capability mod something up to suit my needs?

What do you guys think?

If you using SX when it isn't open source and there is not individual license for it such as paying to use that component in your own commercial software then that theft.

Hi Nightwalker83, every program I mentioned above ZS, ZU, GS, GSE and SX are all open source (GPL).

One downside of ripping out hunks of other peoples' source code and reusing it is support. If the original project makes major bug fixes, reorganizes the logic, etc. you have the support burden of mirroring those changes in order to keep in step. In some cases you won't need the upgrades, but a serious bug found and fixed 10 generations down the road might make it tough to port that bug fix over.

Code intentionally encapsulated for reuse minimizes this. In many cases updates won't require any breaking changes to the interfaces, and when there are breaking changes they tend to be fairly easy to accomodate. That's because the people supporting this 3rd party code have more obligation to maintain interface integrity over the long haul than they would for internal-use libraries within a different type of project.

If this is your partner's argument there might be some merit to it.

I'm unaware of any API exposed by MS Paint and I've never seen any source code released for it. I hesitate to imagine how the hell you're "incorporating" that into another project. Window spelunking, hijacking, and cross-process messaging get more locked down every Windows release, so that's not a reasonable approach anyway.

That's not really his argument. His argument is that it unprofessional to modified others' source code without writing one yourselves. It is almost an embarrassed feeling. He considers GS as an competitor and asks why would we advertise GS with SX.

My arguments are, why we re-invent the wheel? There is no competition. We are all non-profit groups who develop open source applications purely for usability. As long as acknowledgement is given, why not use existing code when possible?

Your point about having to inherit others' bugs is valid; however, that has not been an issue yet. I have got a process going on how to incorporate the code.

The way to use MS Paint is by providing the mspaint.exe path to SX and pass arguments. Cannot do that with GS because with passing command line arguments GS works independently and does not close.

It's an interesting situation. I can see both sides, and both have some sound points.

One question I would ask would be this: Having already used GS code in the earlier version, could you really create your own version without that version being heavily derived from the GS code? If you fully understand the GS code, and you are throroughly happy with what GS does, wouldn't you end up just writing something that is so clearly a knock off that you really ought to acknowledge the inpiration?

I don't see why it's unprofessional at all. Surely the whole point of open source is that you're putting it out there in the hope that other developers will take it further. If GS don't want you to re-use, why did they release it as Open Source instead of black boxing it and selling it under license?

I also don't really understand how you call anyone else "competition" in the Open Source arena. Open source isn't meant to be about competition, it's about collaboration.

From a legal standpoint you should be fine as long as you adhere to any license conditions. From a moral standpoint I think you're fine as long as you're not using the software in a way that the original devs would object to, so maybe contact them and ask if they're happy for you to re-use it unless you're sure they wouldn't mind.

I think there are a couple of arguments against what you're doing, e.g. Dilittante's maintainability issue, but they're about practicality rather than morality.

Also, consider what your goal is. Is it to produce some working functionality or is it to hone/prove your skills? If it's the former then re-using someone else's work is fine as long as they're happy for you to. If it's about honing or proving your skills then, of course, it makes sense to do it yourself.