I'd suggest starting out with nearly "perfect" paddle control and then adding in "mistakes" until you've reached a difficulty level you're happy with. Fortunately, near-perfect paddle control is pretty simple logically in pong.

The following assumes a normal pong layout with a paddle on each side of the screen. If you have a different layout you'll need to adjust as appropriate.

First, the logic for our "perfect" control is as follows:

• IF the ball is moving away from the paddle, try to move the paddle so it is centred vertically.
• IF the ball is moving towards the paddle, try to match the paddle's y coordinate (assuming the origin is the centre of the paddle) to the ball's y coordinate.

If you wanted to include different difficulties this could possibly be the AI for your "hard" mode, although you should only make a player play against this AI if your game is set up in such a way that it can become impossible for the paddle to hit the ball. The only possible improvement on this would be to predict the ball's path and move towards the final location rather than matching the y-coordinate, but as we want a beatable opponent it would be silly to bother with that extra logic.

Next, just add some mistakes, selecting one or more from the following:

• Over-shoot: rather than attempting to match the y-coordinate exactly, just give the paddle regular "up" or "down" updates, so that it might move further than actually necessary and have to adjust. This will often result in "jittery" paddle movement, but if you watch a real player you'll find they are often jittery too!

• Delay: slow down the paddle's reaction times when starting it's movement (or when stopping it's movement, to again achieve an over-shoot!). I'd suggest a random delay of little more than 1 second (perhaps 0.2 to 1.2 seconds?), as too long will be obvious and make your AI look intentionally stupid. Have a play with the numbers to see what feels natural.

• "Jitter" when waiting for the ball to come back. Real players often move towards the centre (as described above) when the ball is moving away... but then they get bored, and move the paddle up or down a bit. This can result in it being slightly harder to reach the ball.

• "Wrong button!": you might occasionally just outright move the paddle in the wrong direction. This should be used very sparingly (1 out of 20 paddle movements or less), and you should never move it very far, otherwise it will become obvious you're trying to lose the game. If thrown in very occasionally this one can help with the illusion of human-like input however.

Does that help? <img src="smileys/smiley1.gif" border="0" align="middle" />

Oh, and I'm not aware of any option to use an alternative coordinate system with Construct 2; I wouldn't think it all that likely that adding one would be a priority given how common the system currently in use is either.

Hope the explanation helped satisfy your curiosity. <img src="smileys/smiley1.gif" border="0" align="middle" />

This is actually pretty common in computer graphics: as an example, that's how Windows itself does it! Another example would be coordinates within the browser window. I expect the original reasoning for this probably relates to how a CRT draws it's image: left-to-right, and top-to-bottom.

It can trip up people who aren't expecting it, but it's no more easy or difficult to work with than the alternative.

Firstly we'll quickly deal with a common misconception -- it doesn't matter if you're releasing your games for profit or for free -- Intellectual Property rights (that is, copyright and trademarks) still apply either way, and if you're infringing upon someone else's rights you may receive a cease & desist notice or be sued either way.

That being dealt with, as I briefly touched on above the laws you're dealing with fall under "intellectual property protection", and the ones that concern you are:

• Trademark: deals with distinctive names and/or markings used in trade. Examples include the name "Microsoft", and the Nike "Swoosh" (tick shape).
• Copyright: protects the expressive form of an idea. Examples being a book, or a piece of artwork.

Patent law can occasionally apply, but isn't something you're likely to have to concern yourself with. A patent protects a process by which something is achieved.

So, you can't use someone else's trademarks without their permission. In video-games this will usually mean the names of existing games (as well as movies, books, etc.!), major characters (you can use the common name "Tom", but you can't use the specific name "Lara Croft"), and logos. Don't use any of these things. Trademarks also only apply to the market in which you are trading -- there is an "Apple" computer company AND an "Apple" music label for example.

You also can't use someone else's copyrighted material without their permission. This means you can't use the dialogue, instructional text, sound effects, graphics, etc. from an existing product, and also applies to "derivative works", meaning that you shouldn't base your own work on an existing piece of work; i.e. if you create your own version of Mario or Sonic, it is a derivative work and you're still using copyrighted material.

All that being said, you can't generally apply any of the above protections to game-play, so as long as you create (or legally obtain) all your own artwork, sounds, text, etc. and don't use any trademarked names or logos you're able to make a game that is played in the same way as another. For example, you can make a "falling block game", but you can not make "Tetris".

One last quick note, I'll briefly mention "Fair Use", which gets brought up almost every time intellectual property is discussed. Fair Use is an exception to copyright laws which can apply in certain situations, and allows you to use copyrighted material without permission. Examples might include quoting a copyrighted piece of text, or making a parody version of a song. The problem however is that there are no strict rules or limits on what exactly constitutes fair use -- there's no percentage of a work or amount of words (I recall an example where someone was sued for using just 6 words from a speech) that are definitely safe to use, and only a judge can decide if fair use applies in any particular situation -- don't fall for the trap of assuming fair use will definitely protect you.

To summarise, you should be fine as long as you check that the names and titles you want to use aren't already in use, and as long as you aren't using anyone else's artwork, sound effects, help text, dialogue, etc.

...and finally, I am not a lawyer, and if you're concerned about this and want to be absolutely sure you should consult with one.

Does that help? <img src="smileys/smiley1.gif" border="0" align="middle" />

He's saying it would likely be an unpleasant user experience; a tablet might be ok, but a mobile phone isn't really a great device to be editing a complex project with.

Additionally, if Scirra were to consider the idea it would hardly be something they could charge a small extra fee for -- they would have to create a new editor for mobile devices, essentially from the ground-up.

There's a tutorial on How Construct 2 licences work that will probably answer your question; specifically, there's a section towards the bottom on "using your licence".

Essentially, you should receive a licence file in an email, usually soon after payment is received, and you then copy this file to either "My Documents" or to the location where Construct 2 is installed.

If you're ready to move on from the free version, you would want the Standard Licence; if you look at the comparison of the different versions on the purchasing page you'll notice that the Standard and Business licences have exactly the same features -- you only need the business licence rather than the standard if you have made more than $5000 with your Construct projects, at which point you can easily afford to upgrade.

If you're still young, you should probably discuss the purchase with your parents, and show them the purchasing page with the comparison of the products as well as some of the cool games you've already been able to make.

Hope that helps! <img src="smileys/smiley1.gif" border="0" align="middle">

Would starting a html5 gaming website be a good source of income for my games

Yes, creating your own HTML5 gaming website is certainly one potentially good way of making some money from your games.

Advantages include having total control over both the games and website, not having to share the income as you typically would with a portal (where you usually get x% of any money made), and not having to share the site with other games unless you choose to do so.

Potential disadvantages are that you'll need to host the site yourself, you'll need to work hard to gain an audience (popular portals already have a massive player-base), and you'll be doing all the work yourself -- any problems with the website will be your job, as well as making and maintaining the games, marketing, implementing monetization, etc.

I would normally suggest a hybrid approach where you host games on your own website and submit to popular portals such as Kongregate. Mobile platforms (iOS, Android) can also be a good potential market, although for more complex games performance can currently be a significant issue -- this will only get better with time however.

Hope that's helpful! <img src="smileys/smiley1.gif" border="0" align="middle" />

Have you tried out the free version?

Are you happy with how the software works, and what it's able to do?

If the answers are both "yes" then purchasing a licence is probably worth it to you -- it'll remove the couple of limitations from the free version, and as the others have mentioned above you'll have the opportunity to sell your work in order to make back the money.

The best way to sell your games really depends a lot on how you're planning to make your money (Pay-to-play? In-game purchases? Ad revenue?) as well as the type of game you're planning on making, but Android, Facebook and Kongregate would all be potential good starting points -- and there's no reason a good game might not be adapted for all 3 with a small amount of extra work!

If you haven't tried the free version, get it now -- there's no cost to you, and you can see if you really like the software. Personally, I think it's a great package and that the licence is very affordable; it has a great feature set, with more being added or things being improved all the time, great documentation, an excellent and very active community, and a growing set of opportunities to earn some cash by selling your work!

I hope this isn't perceived as rude, but I'm just going to give this topic a single bump, because I think it may have dropped off the first page without being seen by Ashley

<img src="smileys/smiley1.gif" border="0" align="middle" />

Just try the free version, and you'll see how good it is!

...and a quick related suggestion -- could we possibly get an option to "view collision polygons" when working with a layout in the editor, which would overlay each object with a transparent outline of it's collision polygon?

This might help to debug problems where the collision polygon isn't exactly where you think it is -- it would certainly have made my current situation a lot easier to figure out at a glance, as I needed to line up the collision polygons of a number of objects, and it wasn't immediately obvious based on the image of the objects exactly where that was.