X1 Complete! Level 1 is now playable!

It was not easy.. but nobody said that it will be!

After an extremely grueling month and loosing a bunch more hours of sleep and exercise, we finally finished X1 on time! Level 1 is now playable! Hurray! Here's how our release chart looked like.

We were pretty much on schedule in our sprints but the effort that we had to put to keep up with the schedule was significant! And again, it was not easy - but we did it :)

So what's next? Now, we have to move on to complete our X2 milestone. This means completing 5 more levels, 10 more enemies, 4 more primary weapons, and 2 more sub weapons! And to make matters worse, all of these have to be finished by the end of November! That's right, feature complete by the end of November. This will require an extraordinary effort from the team but I am very positive that this is possible. Here's a video of how our game looks like. I hope you enjoy the fruit of our labor :)

Cheers,

Jim

Level 1 Boss Fight!

Well, August has been very long, hot, and busy but I finally managed to finish the boss fight for Level 1! Here are some of the screenshots that I've managed to take (gotta learn how to capture videos really soon!):



Level 1 is almost done - all it needs are just a bit of polishing and of course, the other big thing in my list - Collidable Terrains!

Cheers,
Jim

Starcraft 2 (finally started to play.. project in danger..)

Well, it was inevitable. Who was I to resist the temptation of not playing the best ever RTS of all time? After saying to myself a hundred times that I'm not going to play Starcraft 2 until I finish Doodle Space Wings, I finally succumbed to the temptation and got the game after my dentist appointment :) So, after playing 5 missions on the Terran campaign, I lost nearly 6 hours of development time - but I've successfully implemented the homing missle, sub-weapon item pick-up, player hit cue, and player dying animation. So all in all, it ain't bad :) And the plus side is, I've picked up some really cool hints from StarCraft 2 on how to better our doodle side scroller! Also, one really cool thing about that game that I really appreciate was this mini-game called "The Lost Viking"! It is also a side scroller game that I have started using as a reference and as a point of comparison to our doodle game. So yeah, the weekend was pretty productive - all in all. I will try to power through the next wave of tasks for this week and hopefully, the game will even be in a better shape!

Cheers,
Jim

2 types of Bullets, Collision Detection, Game Items, and a whole bunch of other stuffs are now implemented!

Well, it's been a while but I'm happy to say that I've made a very good progress with the game that we're making! And because of that, I've decided to treat my self to a 3-day trip to Tofino last week and not work at all :) I needed the break badly as I felt like my head was about to explode from continuously working on this project! Anyway, here are the new features that I've added to our game:

1. Really fast broad-phase collision detection
2. Game Items (Health, Speed Up, Power-Up, Weapons)
3. 2 Types of Weapons (Fireball, Gatling) with 5 levels of power-ups
4. HUD (Health meter, Score, Lives Left, Pause)
5. Item Spawner Enemy (Mr. Wiggles)

..and a bunch of other small things!

Despite all these wonderful achievements and me working on this ~7 hours a day during the night, I'm still behind by 6 tasks! I hope that I get to finish all of these in time for X2!

I've been meaning to post some videos of how awesome our game is quickly becoming but for some reason, I've been too lazy to do it. I promise to try again tonight and do it :)

Cheers,
Jim

EXC_BAD_ACCESS

Yesterday, I was so happy to have finally implemented both the bullets and the collision detection system. The performance was really good that it can even show up to 100 sprites on the screen at the same time - and all of this is happening with collision detection enabled! I was ready to tackle the next feature in my list - which is making the enemy drop items - but that is until our game crashed. I tried to relaunch it again, thinking that it might just be Steve Jobs' fault.. but then it happened again - only this time, it happened after 2 minutes of waiting. Hmm.. I tried to view the console - and there it was: EXC_BAD_ACCESS. I also tried to view the stack trace to see where the error has originated but to my luck, the stack trace was already gone at that point.

Being a new Objective-C developer, I am still not used to it's style of managing the memory although I am aware of how they work and what are the pitfalls that needs to be avoided. But then, it's bound to happen sooner or later and fortunately for me, I found the problem out while our game is still at it's infancy - where there's not much class hierarchy yet. And so I did my research - and according to my research, here are the main reasons for you to get this error:

1. Releasing an object that is already released (this mostly means that you do not release the objects that you are not directly responsible for releasing - unless you have retained it).
2. Accessing an object that is already released (this mostly means that if you'll be working with an object that's passed via a parameter outside of the call stack where it was delivered, then you'd want to retain it).
3. Adding or removing objects from an array that is currently being iterated (ehem..)

Nevertheless, EXC_BAD_ACCESS is that kind of error that doesn't give you a lot of clue as to how and where it happened. All that it gives you is the error name - and a lot of headache. As it was for me, I spent nearly 4 hours trying to debug this single problem only to find out that I was modifying the array that I was currently iterating! After tweaking the code a bit, our game is finally EXC_BAD_ACCESS free! Yay! So yeah, I'm happy that I was able to move past that and move on to the next item in my list.

Cheers,
Jim

P.S. There is an article that I found on the net on how to debug this error:
http://www.codza.com/how-to-debug-exc_bad_access-on-iphone

but for some reason, it didn't work for me. Oh well - still good to know just in case I get this problem again.

Bullets are now implemented!

After the fireworks show here in Vancouver last night (http://www.celebration-of-light.com/), I got stumped with a bug that made all of my actors (bullets and enemies) run erratic. As I was using multi-threading in my factory to prevent a linear algorithm from blocking the UI, I've learned from the past that if you can't explain some bug after 4 hours of investigation, then it must be caused by multi-threading :) So anyway, it has been a long night last night but I finally managed to implement the bullet system in our Doodle Space Wings! I had to rewrite some sections in my Sprite Factory in order to eliminate the parts that were implemented using multi-threading as it had a critical flaw with regards to accessing critical sections of the code. Anyway, I'm happy with the new solution since even without the threading part, I still managed to meet my 60 FPS goal even when the screen was displaying 50 sprites at the same time!

I also had to redesign some of my sprites in order to make them more attractive. It's hard to do everything by yourself but I guess it's a path that every low-budget indie developers have to take. I'm learning a lot of things right now and I'm happy with the way the things are progressing despite the fact that I'm loosing more sleep :)

So next stuff on the list - collision detection, weapon drops, implementing 5 more kinds of bullets, and loosing more sleep :)

Jim

Goal: 60 FPS

It's been a tough week. I was barely able to keep up with my schedule and the goal of having 60 FPS is not making it any easier. Our Sunday hike at Garibaldi Lake took a toll on my body - and now, I am playing through the pain. Nevertheless, after cutting back my sleeping hours to around 3 to 5 hours, I have managed to keep up with my schedule, still maintain the 60 FPS goal that I want to achieve, and most importantly, hike and bike around Vancouver! Anyway, so how do you go about keeping a high and consistent frame rate? Well, I keep the following guidelines in mind when designing our game:

1. Do not allocate a lot of things in your main game loop - especially during the draw routine
2. Try to reuse your sprite allocations as much as you can. I've implemented a sprite factory which maintains a sprite pool that can reuse sprite allocations. This ensures that dynanic memory allocations during the game loop are kept to a minimum.
3. Cache complex mathematical results.
4. Rely on O(n)-based algorithms only as a last resort. Choose O(logN) or if possible, O(1). For example, using a hash table is a lot better than using an array when you need to search for an item as it cab give you O(1) when using a very good hashing function.
5. If you have to use linear-based algorithms, sorting the array will usually yield better performance if doing search.
6. Remember the trade-off - memory vs performance - you can gain performance improvement by sacrificing some memory.
7. Do not try to reinvent the wheel. Check if the framework that you are using already supports what you are trying to do. The guys who built the framework that you are using spent a lot of time working on it and what they did is probably better than how you will be doing it.

8. Keep the texture size in check. It usually boils down to using a texture size that is a power of 2 (e.g. 512x512).

Hmm.. I guess that's my list for now - I might add some more if I learn something :)

Cheers,
Jim

I can now see it on the screen!

One thing that's really good about the summer is that the number of things that you can do outside of your house exponentially increases. The days are longer, the nights are warmer, the reality shows are in full swing, and well, it just gives you a perfect excuse to not stay home, sit in front of your mac, and do programming! If you live in Vancouver like me, you'll know how many dark, rainy, and cold months we've had to endure before we get to this point - and so whenever we get a chance for a sunny and warm day, we get out as much as we can!

I love the summer but sometimes, I worry that I enjoy it too much that I will have to move my X1 milestone after the summer! But nevertheless, we're still on track and despite the wonderful BBQ, mountain trips, biking trips, and waterpark slides that we've done over the week, I still managed to complete some key of the tasks that I needed for that week and all it took was to move my sleeping time to 2:30 in the morning :). Anyway, here's a small video of what I've managed to accomplish so far. The background still needs some rework since I think it looks very messy! I will try to reduce the doodles to make it look cleaner. Today, I'll probably try to make the ship move using the accelerometer and touch... but after do my biking exercise around science world :)

Jim