APB

[Ynot.zer0]

For the first time in about 20 years, I just played APB on my CPC.  Does anyone in the programming world have any source code on how to achieve that type of gameplay?  (did all the original authors of these games burn the source code on 31st Dec 1999?).  I'd love to learn how to do that sort of design as I have a game concept in mind, but not the know-how on how to make it a reality.  any advice welcome!

[arnoldemu]

For the first time in about 20 years, I just played APB on my CPC.  Does anyone in the programming world have any source code on how to achieve that type of gameplay?  (did all the original authors of these games burn the source code on 31st Dec 1999?).  I'd love to learn how to do that sort of design as I have a game concept in mind, but not the know-how on how to make it a reality.  any advice welcome!

I am confused:
are you joking or are you serious?

APB of course is converted from the arcade original.

So if your serious, *which* elements do you mean?

[AMSDOS]

I'm a bit of an APB fan, I presuming the original poster wants to make a game like APB where you're controlling a Police Car rounding up all the Hitch hikers, Untidy vehicles, Honkers, and can catch the odd crook in their car by running them off the road and beat a confession out of them. The game has some nice scrolling, though the game screen is quite small (Spectrum sized), though is a conversion from the arcade.

Perhaps the best way to approach a game like that is to take the BASIC elements of it and add things to it as you see fit.

For example in Issue 108 of Amstrad Action was this simple Car like game from Chris Morgan:



So from that to have a game more like APB you'd need Brakes, Obstacles (Cars for instance), the ability to Shoot the right offenders with your siren, APB obviously offers extras such as Guns, Extra Speed, Faster Acceleration and time limits. So to make it kind of more like APB perhaps looking for BASIC games which have you avoiding obstacles is something to consider. The one which comes to mind is a type-in from AA34 call Desert Attack which unfortunately is a bit big, though I've typed it in. The thing about the game is while it uses up most of the screen, it lets you fire at the obstacles ahead, perhaps even with a small amount of tweeking, it could be somewhat simular.

[MacDeath]

APB was a great game on CPC.

[Ynot.zer0]

@arnoldemu:  am serious, no joke.


I was visioning something like a cross between APB and GTA(1):
http://www.youtube.com/watch?v=t8tvADi-uA8


So, I was curious just how you could map out the car road / routes, how to handle the concept of travelling around a town (albeit a mostly rectangle one) and moving the graphics accordingly (from a birds-eye view), how to handle the collision detection (okay to bump the kerb onto the grass, but not okay to drive into a building) and then how to handle the automation of the other vehicles..... 




@cp/m user: thank you for the example BASIC code.  I think I'll make a start in BASIC and once I have a working prototype, I'll look at asking the experts how to translate it into ASM.  (best learn to crawl before walking / running / sprinting, etc...)

[MacDeath]

GTA1 is actually an 8bit styled game...

[AMSDOS]

@arnoldemu:  am serious, no joke.


I was visioning something like a cross between APB and GTA(1):
http://www.youtube.com/watch?v=t8tvADi-uA8


So, I was curious just how you could map out the car road / routes, how to handle the concept of travelling around a town (albeit a mostly rectangle one) and moving the graphics accordingly (from a birds-eye view), how to handle the collision detection (okay to bump the kerb onto the grass, but not okay to drive into a building) and then how to handle the automation of the other vehicles..... 




@cp/m user: thank you for the example BASIC code.  I think I'll make a start in BASIC and once I have a working prototype, I'll look at asking the experts how to translate it into ASM.  (best learn to crawl before walking / running / sprinting, etc...)

I always remember AA critising APB for the sheer amount of Multi-loads it would do in their review (AA50), unfortunately I've never experienced this and only checked it out when it was on NVG, sadly that cracked version was horrible cause some of the levels had cars all over the place, you can find a DISC version of the game in ADATE which is heaps better!    APB would naturally work as a game with Level Data which represents where everything is, road, buildings, bushes, etc, the figures which travel or are placed along those levels would be restricted to where they can move to.

I've attached a copy of Desert Attack, it's perhaps not the best example and being in BASIC is has it's limitations (definitely), another game you might want to check out is Chug, again perhaps not the best example (I reckon it's okay), and shows how Level Data is structured, another game which is a good example of avoiding objects is Lawn Mower Simulator from AA52 (unfortunately I haven't got a copy readibly available).

I keep thinking that perhaps there are better examples of programs which might have been an influence from APB, perhaps something which might have been published in an European magazine(?) unfortunately I'm not at all familiar with the stuff which might have been in European magazines besides AA & the later ACU. Another interesting game which combines m/c & BASIC which has a car in it is Skoda Simulator which was in AA96.

But it's always good in a way to write understandable code and then put it into Assembly! 

[arnoldemu]

@arnoldemu:  am serious, no joke.


I was visioning something like a cross between APB and GTA(1):
http://www.youtube.com/watch?v=t8tvADi-uA8


So, I was curious just how you could map out the car road / routes, how to handle the concept of travelling around a town (albeit a mostly rectangle one) and moving the graphics accordingly (from a birds-eye view), how to handle the collision detection (okay to bump the kerb onto the grass, but not okay to drive into a building) and then how to handle the automation of the other vehicles..... 




@cp/m user: thank you for the example BASIC code.  I think I'll make a start in BASIC and once I have a working prototype, I'll look at asking the experts how to translate it into ASM.  (best learn to crawl before walking / running / sprinting, etc...)

Generally the roads etc would be created as a tile map.
So you need difference pieces to make the different angles of road etc.
The GTA thing is an effect over the top to make it look like perspective when it's just a trick.

In terms of the handling the collision etc, this can be done by looking at the tilemap, the same is true of driving onto the grass and adjusting the speed or similar, you look at tilemap, look at tile index there and make a decision (e.g. it's grass, so move slower), or e.g. it's curb, so do something there.

So this should cover most of the graphical display. As for how to move other cars around the city, well you could do this with a navigation map, put a point at each junction and from the point list the directions you can travel. Then you can make the cars move along and follow the junctions.. making it look realistic is a bit more hard work, and of course will suck the cpu power.

So try a simple approach first, it may well do what you want for the Amstrad.