Performance with Swing graphics...

Question

Hey all, I have a small 2d multiplayer game that I'm writing in Java. The trouble is that, despite it being simple, it runs pretty slow. I have a few theories about things that I might should do to speed it up, and I wanted to know if you guys agreed with me and if, perhaps, i fell into some sort of newbie pitfall that I didn't notice...
1.) Running all the clients and server off of one machine. I suspect this is one good reason why it runs so slow, but my system is good (a new 1.5ghz G4 PowerBook with a gig of RAM) and I haven't gotten a chance to fire up everything on separate machines. Could it be that running 3 windows updated every 100ms is the only problem? :)
2.) Not getting the UI's running on the event dispatching thread. I know, this is a big no-no and I have to do it regardless, but does it affect the performance?
3.) Elliptical clipping of the viewport. The game shows a circle around each player, does clipping the view in this way hinder the speed?
4.) Collections! I discovered the collections framework recently and have the game objects organized into Java collections. In theory, though, once the game starts, there's no need to add more game objects (so they don't need to grow dynamically). I'm wondering if it would be faster to read in everything at the beginning into a collection, then convert it to an array before the game starts and just use that the whole time.
5.) Alpha blending. I have a few translucent objects in the view. Should these be eliminated? It does seem to run a bit faster with them gone. I have some weird ghost translucent objects that I'm trying to track down, so I suspect that'll cut the number of translucent things in half, which should give a speed boost.
I'm sure it's difficult to tell for sure without the code, but the programs are pretty big and the questions are general. Any assistance would be greatly appreciated.
In the meantime, I'll continue hunting for performance discussions and working on the code!
Thanks!
-Zach

Answer 1

run a profiler. this should help you determine where the bottleneck is.
1.) Running all the clients and server off of one machine. i'm assuming that the server will be put on a different machine when your app goes into production. but during testing, unless your server do a lot of stuff , then it should not matter.
Could it be that running 3 windows updated every 100ms is the only problem? :not sure by what you mean Window update?
2.) Not getting the UI's running on the event dispatching thread. I know, this is a
big no-no and I have to do it regardless, but does it affect the performance?yes..it's a big-no-no!! how do you paint the UI? the great thing about th eevent dispatcher is that when you issue multiple repaint(), it does not paint each time..rather..it check a flag to see if a repaint is need..and then repaint th ecomponent. so, it may just repaint once. if you repaint manually..you may do this multiple time...which could slow down your application. Just beware of doing anything in the event dispatcher thread that could slow down your app or even lock th eGUI components.
4.) Collections! .. 'm wondering if it would be faster to read in everything at the
beginning into a collection, then convert it to an array before the game starts if this is the case..yes, using array would be faster, since th elookup is determined using th ebase address multiplied by the index and the size of th eelement. for object array..the size of the element is the adress where th eobject reside in the heap.