More than I can chew: Timers?

Akom

Ok, heres the deal... a couple of friend's and myself decided we were going to learn PHP and create a game based on a game I saw a last year. This is for our final project at our technical college.

So far, everything has gone smoothly. Now, though, we are at the point where we want to set a delay to have things created. (It is a "RTS" based game... you create buildings and soldiers and go out and fight other nations) Lets say you want to make a house. You click the create button for house. I do not want the house to be created instantly, I want there to be a delay of, say, an hour (this game is intended to be played in the background as you go about your daily activities). How do I set it so that the database dosn't update the "houses" field for the specified player until the hour is up? Also, it would be cool if I could show a count-down timer to when the house would be completed.

The other issue we have with timers is that we want to be able to have resource havesters running constantly. Say a player puts 2 of his population into gold mining... that should be 2 units of gold per hour (according to the way we planned the game out). How do I accomplish this, so that once per hour it checks how many miners the player has, and credits their gold columb on the db with the right amount, even if they have left the game web page / logged out?

Thanks ahead of time...

Brian

Sxooter

The first one's pretty easy, put in a creation time, and then post-date it, and make your select queries use a "between game_start and now()" kind of query.

The second may be better answered by having a seperate table that has things like number of miners and how long they worked, and sums them up, again with the creation date thing or something so you can tell when to include it.

drawmack

for the second one you need something like this

CREATE TABLE IF NOT EXISTS resources (
  ID BIGINT NOT NULL auto_increment,
  ResName VARCHAR(100) NOT NULL,
  Yield INT NOT NULL,
  Units VARCAHR(100) NOT NULL,
  PRIMARY KEY (ID),
  UNIQUE ResName (ResName)
)

CREATE TABLE IF NOT EXISTS player_to_resources (
  ID BIGINT NOT NULL auto_increment,
  PlayerID BIGINT NOT NULL,
  ResID BIGINT NOT NULL,
  PopAss BIGINT NOT NULL,
  LastUpdate TIME NOT NULL,
  PRIMARY KEY (ID),
  INDEX PlayerID (PlayerID)
)

from these tables the manipulations you need should be obvious.

tomhath

How to set up a timer depends on the operating system you have available. On a Unix-like system you would set up a cron job to run periodically. On a MS platform you would need to set up a Service that does something similar; some databases (e.g. MSSQL) have the capability to run tasks at regular intervals.

Probably every fifteen minutes would be enough for your situation, but be sure it will finish before fifteen minutes; better yet, build some logic into the task to shut itself off if the previous cycle hasn't finished so only one at at time will be running.

It's worth doing a little research and learning how to write a cyclic process, they're very useful.

http://www.unixgeeks.org/security/newbie/unix/cron-1.html

http://www.codeproject.com/dotnet/notificationservice.asp

Akom

Thanks for the replys... I'll be looking into using your suggestions on Friday (when our group gets together to work on the project).

About using Cron an the like.. I had read about that too, but it sounds like you need physical access to the server. We are having the game hosted on a web server that one of our instructors uses. We have no access to the actual server, so if there is anything that would actually need to be installed, server side, that is not an option at the moment. I don't really know how that works though (cron) so if it is possible to set up with only access to the FTP, let me know.

tomhath

cron is a daemon process that is almost certainly already running. You need to set up the crontab for some user (doesn't have to be the web server, just be able to update the database). Your instructor will probably let you specify what to run and when (unless of course you are hijacking his machine) 😉

Sxooter

I'm gonna repeat my point that you are better off using date / time set in the database and use a dynamic query that picks the right set of records rather than relying on a cron job to make the changes you need.

Adding a cron job here just makes it more complex and error prone, setting up your SQL to pick rows based on timestamps (datetime type in MySQL) means you aren't relying on a cron job to do things every x minutes, which means that when you run your query, you'll get the exact state in time that you want right then, not the one that was set X minutes ago by a cron job.

That's my humble opinion... Think about it.