Wednesday 26 August 2009

Vista Probs - Slow Internet Speed

I had a phone call from my younger sister today - her fiance's PC was running strangely. Sometimes the internet was fine, other times it ground to a halt. They'd checked for spyware and viruses - but couldn't find anything wrong.

Whilst logged in as an administrator open a command prompt (or use the "run as" option on the command prompt shortcut).

Type the following command:

netsh interface tcp show global

This should return a fair bit of information, but the line we are interested in is the one that starts:

Receive Window Auto-Tuning Level

If this shows anything other than "disabled" then you can try entering this:

netsh interface tcp set global autotuning=disabled

This should return "OK".

At this point we tried browsing the web - and lo-and-behold it was browsing at a more normal (ie fast) speed.

If you want to set it back to the way it was, you can try this:

netsh interface tcp set global autotuning=automatic

A quick fix, but one that is worth remembering.

Chaos Caverns II - Dev Diary - Part 2

Updated 28/08/2009

As the original post is getting a bit on the long side, I'll be continuing the Chaos Caverns 2 dev diary here.

I've been taking a couple of days off to think through what direction I want to take the game in. There are still a couple of things that I'd like to add in, conveyor belts for example, but nothing that is likely to stop me from finishing the game.

I've been toying with the idea of releasing a demo of the game so far, but to be honest I'd rather release a finished (and more importantly tweaked and polished) game this time around. With that in mind I'll be putting out a call for volunteers to beta-test the game once the game is a bit further along. Interested? Then feel free to get in touch either via the comments on this blog post, the development thread on Retro Remakes or by email at dans.remakes(AT)googlemail.com.

Right, enough gabbing for now - back to coding!

28/08/2009

One of the problems with being less than artistically gifted is that doing the graphics for a game takes a lot longer than you might expect. Trying to make animated sprites takes even longer.

Rather than trying to create the sprites from scratch I'm (mainly) shinking and editing images from photographs. This is giving the game a much more "unique" look and certainly makes up for my lack of artistic talent.

Saturday 22 August 2009

Sky+ problems: Freezing picture

Sky+ is one of the most useful gizmos that I've ever bought. It really has changed the way that my family and I watch TV. Being able to pause and rewind live TV and the ease of recording stuff is just fantastic.

I've had relatively few problems with the box. Last year I had some severe picture problems, but a slight adjustment of the angle of the receiver dish solved that. Recently, however, our Sky+ box has started locking up whilst viewing live tv. Rewinding a few seconds seemed to resolve it. Until today that was, when even recorded programs were locking up, followed by the Sky+ box shutting itself down.

These days if I've got the choice between phoning customer support or checking on Google, customer support comes second. One thing that is obvious is that an awful lot of people are reporting the same problem.

Now, I'm assuming if you've read this far you are interested in how to fix it, yes?

Captain Obvious says: "Kids, if you follow instructions posted on websites and things go wrong it is YOUR PROBLEM, not theirs."

Step 1: Power off the Sky+ box at the mains, an leave it powered down for at least two minutes.

Step 2: Restore the power to the box and start up. If your box is like mine it may take a few minutes to start up.

Step 3: Click the "Services" button on your Sky+ remote and go into the "System Setup" menu.

Step 4: Press "0" on the Sky+ remote, then press "1" and finally press "Select". This calls up the "Super Secret Hidden Menu" (seriously, it does!).

Step 5: At this point there are two options you can use. One will remove everything from your system and wipe the internal hard drive, the other performs a disk check, fixes file-system problems and hopefully gets you back to a working state.

So, if this is the first time you've tried this, you will want to highlight the option "Sky+ Planner Rebuild" and then press "Select". This should run the maintenance routines on your box, which will power itself off once it has completed.

Once you go back into Sky+ you will need to check through your list of recorded programs as any recovered but corrupted programs will need deleting. It is also worth noting that some people report problems when their Sky+ box is over 90% full, so deleting some unwanted programs may not be a bad idea either.

If this doesn't work then you can try the final option which will wipe EVERYTHING from the planner, and that is "System Reset."

Luckily for me deleting some old programs and performing a planner rebuild seems to have fixed my Sky+ box, so I've not needed to nuke the system. Apparently this is the routine that Sky customer service will tell you, but seeing as I didn't phone them I can't confirm that.

So if you are having the same issues as I did (and assuming you've taken note of the sage advice of Captain Obvious) then this might be worth trying.

Saturday 1 August 2009

Chaos Caverns II - Dev Diary

Updated 21/08/2009

A couple of months ago there was a discussion on Retro Remakes relating to creating platform games. The discussion grew to the point that I got a bit carried away and added an early (very early in fact) version of the source code to Chaos Caverns, as well as writing some pseudo-code to demonstrate how simple it is to make a basic platform game.

The thing is that once I'd written the pseudo code I found myself wondering if it would actually work, and the only way to test this is to bloody well write it. And so, using my pseudo code as a template I wrote a basic platform game engine. It works too. In fact in some respects it works better than the code for the original Chaos Caverns.

So now I'm in a bit of a quandry as I'd already been planning an update of Chaos Caverns and was in the middle of fixing up the old code.

So on the one hand is the original Chaos Caverns, which has already been expanded to allow me to create a flip-screen arcade adventure in a similar style to Jet Set Willy and pretty much only needs the levels completing to make it into a completed game.

On the other is the new code sitting in the Testplatform2 folder. This isn't quite as complete as the other but has some important improvements:

1 - It has been upscaled to 640x480. This is double the resolution of the original and does look a lot nicer.

2 - I've written the new version using Object Oriented methodology, rather than the spaghetti code of the first one. It has taken longer trying to remove things like the level transitions from the old one than it has to write the new one from scratch. Also I've got the benefit of a couple of years experience compared to when I started writing Chaos Caverns.

3 - Even on the short test level I've created it feels rather nice to play.

4 - It should allow me to create a much better game, more in a 16bit retro style than the 8bit style of the first one.

Point 4 is the decider really. Even though I could knock out a quick game using the old code base I wouldn't be as happy with it as I think I could be with the new game engine. So I'm re-implementing the functions that are still missing, which is a slightly frustrating exercise, but the new features (such as animated tiles, and each tile being available in multiple states) already there makes up for this.



So here we are at the birth of what I'm currently calling "Chaos Caverns II".

I'll be updating this post with the development diary as time goes on, so stay tuned!


2/8/2009

Level switching code has been added to the game, so now I can start building the game proper. I've put together three screens as a test and it all works rather well. At this point it is starting to feel a bit more like a proper game.

Next step: Items and enemies.


12/8/2009

Summer time isn't the most productive time for programming, but have managed to track down and fix some bugs, including an extremely annoying one which caused the player to fall through the floor, but only when existing the screen to the left. Exiting from the right worked fine. Finally managed to fix it by re-arranging the movement code to make sure that the move down / platform checking code ran before the left / right movement and exit code.

I've also spent some time tidying the code up a tad, and starting to add in the code for the enemies.

I'm dealing with the enemies in a different way to how I did in Chaos Caverns. This time all the enemies from all the levels are read into a single array when the game initialises - rather than refreshing the list at each level change. This allows me to "kill" enemies and for them to stay "dead" between screen changes.

I'll be dealing with objects in the same way. Some objects will allow you to destroy enemies, so for example, collecting a pin will allow you to destroy the giant beach balls. More on that later...

To make the game feel a bit more like a game and less like a demo I've added a place-holder title screen.



OK, so that's a long way from brilliant, but at least it makes testing the game a whole lot easier in that once you've lost all your lives you return to the title screen rather than just quitting or jumping straight back to the first screen.

I've also added a music track for the title screen - again this will probably change before the game is finished - but for now I'm using Mozart's Rondo Alla Turca (thank God for classical music in the public domain).

As a side note - if any budding musicians are reading this and feel like donating a music track or two then please get in touch.

As of midnight I've got a moving enemy on screen (at last!) and can move onto the enemy collision detection routines tomorrow. *yawn*

13/8/2009

Oh no, Thursday the Thirteenth!

I'm not superstitious about the number thirteen, but today hasn't been a great day, work-wise.

At lunchtime we lost access to the internet, email, our advertising system AND our page transmission system - while we were half-way through transmitting a newspaper that had a 1pm deadline. It was down for a couple of hours due to an alleged power-cut in Oxford.

So we had three hours of dealing with complaints about something that we've got no control over.

Wonderful.

Follow that up with me being on call, and getting called back in twice (although as luck would have it I was able to deal with both calls remotely).

On the bright side I've got collisions with the first (and currently only) enemy in the game working. So that's nice.

15/8/2009

Motivation is often an issue when writing software for yourself. When things get tricky, I try and add "one feature a day". This at least gives some impression of the game developing rather than just lurking there waiting for me to complete it.

OK, so sometimes you miss a day - but today's feature is one that makes the game a bit more tricky - and that is allowing the player to die if they fall from too great a height. Not a difficult thing to add but something that I had deliberately left out of the original Chaos Caverns.

This time, however, if the level designs that I have in mind are going to work then this is a feature that I need - otherwise there won't really be any challenge.

Features remaining to be added (and this isn't a full list):

  • Collectible items
  • Killer items
  • Special items
  • Lifts
  • Conveyor belts

Other things to do:

  • Add more levels
  • Add more enemies
  • Add more graphics and sounds
  • Write a proper front-end to the game
  • Add an end sequence
I'll be expanding this list as time goes on. But so far, so good.

16/08/2009

Today's new feature: Lifts. In getting the lifts working I've had a think about how I'm coding the game, and more importantly, how to reduce the amount of routines that I need whilst achieving the features that I require.

The lifts are a case in point. I'd considered making a new game object for the lifts, but then realised the obvious: "a lift is just a platform that moves." So by adding some new parameters to the platform object and creating a "move" method I've got a basic lift working with very little new code required.

I've still got to code the interactions between the player and the moving platform (ie. if the platform is moving left or right then the player's movement follows it). Easy for left to right, slightly more complex for up and down. Especially when I need to find a way of slowing down the lifts a bit as by default they are a bit nippier than I'd like.

I was also going to add another object for "traps" - basically killer objects. Thinking about it what is a killer object? In the terms of this game it is an enemy that doesn't move, so if I just use the existing enemy routines with a static enemy then job done!

18/08/2009

Still working on the lifts. As they were running a bit faster than I'd like I've added in some code to create a delay between each move - so the lift will only move every x number of frames. This works well and allows me to have fast and slow lifts as required.

Moving and jumping whilst on the lift works but... sometimes whilst jumping you fall through the lift, and I can't see why. Ah well, tracking down and squashing bugs is all part of the fun.

I've also been re-jigging the player movement code a bit so it should be a wee bit more optimised, as well as a bit smaller. For those interested, at present on a P4 2.8ghz the game uses around 4% of the CPU time.

Update: Bug fixed, so the lifts are now fully working (vertically at least). I've adapted the second screen so that it can only be traversed by using the lift - and it all seems to work nicely so far.

19/08/2009

Now that the lifts are working it is time to start expanding on the code to make this less of a demo and more of a game. With that in mind I've started adding a fairly basic score / level / lives display at the bottom of the screen.



The strange thing is that this revealed another bug: if you dropped from a height into water you'd lose two lives instead of just one.

After one hell of a lot of hunting through the code I finally realised that I was forgetting to reset the fall height, so when the water code killed you the fall counter still contained a value, and because you re-spawned on a platform it treated it as if you'd landed after a long fall, which kills you a second time.

An easy one to fix, but a bugger to track down.

20/08/2009

Today I've been expanding the code a touch (extra baddie movement types, horizontally moving platforms and some other bits).



I've also put together a short video showing the game in action. Not a lot to see so far, but you can get the general idea of the progress so far.

Tomorrow I'm planning to add the code for collectible objects into the game. Once this has been done then the game engine will be basically complete and it will be time to start adding enemies and designing some proper levels.

21/08/2009

Found and eliminated another bug - one that allowed you to pass through a solid block if you hit it precisely on the top corner whilst falling.

I've amended the second screen to add in a horizontally moving platform - which worked first time without problems. Mind you, once you've got the code working for the vertical lifts there really isn't a lot you need to change to get it working for horizontal ones.

I've also posted about this game on the Retro Remakes forum - so a big hello to anyone visiting from there.

Update: Collectible items are now working. Quite simple to add really, providing you remember to use methods rather than functions for your reading / drawing code. Why? Because functions can't access an objects fields (the variables that the object uses). This is a "it's too late at night for this shit" type bug.

22/08/2009

Today has been mainly spent "enjoying" a bout of either man-flu or hayfever. Either one gives the same result - my IQ has dropped so far that it now has a negative value, my nose and eyes are taking it in turns to drip, different parts of me are competing in the "most painful" competition (I think that my back is winning so far). Not surprisingly I've not been especially productive on the old programming front.

That said, I've started expanding the baddie routines a bit, so the beach-ball enemy now rotates as it bounces (which looks cool), I've added a balloon as another enemy, which is also semi-transparent. This also looks pretty cool in action.

I've also started tidying up some of the routines, and simplifying the code in a couple of places.

Continued in Part 2