fluidity & FPS

MickArea · by **MickArea** » Fri Feb 27, 2009 11:41 am

Hi,

I discovered that in my application i lost FPS due to :

02-27 11:31:05.403: DEBUG/dalvikvm(90): GC freed 1110 objects / 57568 bytes in 216ms
02-27 11:31:34.193: DEBUG/dalvikvm(1423): GC freed 11086 objects / 388256 bytes in 116ms
02-27 11:32:24.702: DEBUG/dalvikvm(1423): GC freed 16590 objects / 556688 bytes in 117ms
02-27 11:33:09.542: DEBUG/dalvikvm(1423): GC freed 16144 objects / 536248 bytes in 114ms
02-27 11:33:46.322: DEBUG/GpsLocationProvider(49): NetworkThread out of wake loop
02-27 11:33:46.322: DEBUG/GpsLocationProvider(49): Requesting time from NTP server pool.ntp.org
02-27 11:33:54.562: DEBUG/dalvikvm(1423): GC freed 15763 objects / 524240 bytes in 121ms
02-27 11:33:56.632: DEBUG/SntpClient(49): request time failed: java.net.SocketTimeoutException: The operation timed out
02-27 11:33:56.632: DEBUG/GpsLocationProvider(49): requestTime failed
02-27 11:33:56.632: DEBUG/GpsLocationProvider(49): NetworkThread wait for 300000ms

i don't know why i have so much of GC freed ..
In first i thought that it is due to so much reallocation memory, but after improving the code. I have still the problem !

i make this code but it is worst :

Code: Select all: ///// drawing ////////////////// // the code to regulate the fps : countFrame++; period=System.currentTimeMillis()-start; start=System.currentTimeMillis(); if( (50-period)>0 )delay=(50-period+delay)/2; else delay=5; if(System.currentTimeMillis()-startFrame >= 1000 ) { FPS=countFrame; countFrame=0; startFrame=System.currentTimeMillis(); } ////////////////////////// class RefreshRunner implements Runnable { // @Override public void run() { while (!Thread.currentThread().isInterrupted()) { demoView.postInvalidate(); try { Thread.sleep(demoView.delay); // a 10th of a second } catch (InterruptedException e) { Thread.currentThread().interrupt(); } } } }

I need help, it is an application which need a lot of calculation and drawing.

MrSnowflake · by **MrSnowflake** » Mon Mar 02, 2009 9:25 am

When using a surface, and locking that surface, you get a steady fps, so, your own fps regulation is only necessairy when you want less than 50 fps.

ClockworkAlchemist · by **ClockworkAlchemist** » Thu Mar 05, 2009 7:12 pm

Also, keep in mind that calling sleep() doesn't mean that your thread will sleep() for EXACTLY that amount of time, it means it will sleep for AT LEAST that amount of time. Often it is more.

What are you trying to do? I've written a few small timer / FPS related things while trying to learn how drawing works on android, I might be able to post something that is pertinent to your issue.

MickArea · by **MickArea** » Thu Mar 05, 2009 7:33 pm

Hi,

thanks, I need a way to regulate the fps, because some time android do something in the background and i lost a lot of FPS, like a freeze ...

example :
dalvikvm(90): GC freed 1110 objects / 57568 bytes in 216ms

MrSnowflake · by **MrSnowflake** » Thu Mar 05, 2009 7:40 pm

Sleeping your thread will only make it worse if anything!

MickArea · by **MickArea** » Thu Mar 05, 2009 7:45 pm

i know,

but the goal of this code is to regulate the fps, like this :

time between two frames is too smal, add a delay to get what i want.
time between two frames is too big , reduce the delay to get what i want :p

if i want a 26 fps, it could be possible !

MrSnowflake · by **MrSnowflake** » Thu Mar 05, 2009 8:14 pm

MickArea wrote:if i want a 26 fps, it could be possible !

Then you should take 25fps, as that is coïncides with the 50Hz of the G1's screen.

ClockworkAlchemist · by **ClockworkAlchemist** » Fri Mar 06, 2009 1:23 am

Also, you want to make sure that your application can properly handle variable length updates. I just sketched this out in notepad. It's probably not 100% correct, but you can see what is going on. Note your first update will probably be zero, and this would need some work to handle cases where less than a millisecond had passed. On a related note, does anybody know if the G1 properly supports a higher resolution timer?

Syntax: [ Download ] [ Hide ]

Using java Syntax Highlighting

 
   class RefreshRunner implements Runnable 
 
   {
 
     private long last_time_ms = 0;
 
     private long elapsed_time_ms = 0;
 
     private float elapsed_time = 0.0f;
 
     private boolean thread_done = false;
 
     private void update_timer()
 
     {
 
        long current_time_ms = System.currentTimeMillis();
 
        elapsed_time_ms = current_time_ms - last_time_ms;
 
        elapsed_time = ((float)(elapsed_time_ms))/1000.0f;
 
        last_time_ms = current_time_ms;
 
     }
 
     private void run_simulation(float32 elapsed)
 
     {
 
        // do stuff here
 
     }
 
      // @Override
 
      public void run() 
 
      {
 
        last_time_ms = System.currentTimeMillis();
 
         while (!thread_done) 
 
         {
 
            update_timer();
 
            run_simulation(elapsed);
 
         }
 
      }
 
   } 
 
Parsed in 0.033 seconds,  using GeSHi 1.0.8.4

MrSnowflake · by **MrSnowflake** » Fri Mar 06, 2009 11:04 am

Yup, that's the most important feature any game should have. Because the G1 has an update frequency of 50Hz but any future device may have a higher (60Hz) or lower frequency, so your game would play faster/slower on such devices.

This won't fix your drop in fps at some points, but at least your gameplay won't feel choppy.

MickArea · by **MickArea** » Sat Mar 07, 2009 1:09 pm

ok, i understand.

but in my game i've to move pixel by pixel, i can't make something like that ( lunar example ) :

Syntax: [ Download ] [ Hide ]

Using java Syntax Highlighting

mHeading += mRotating * (PHYS_SLEW_SEC * elapsed);
Parsed in 0.030 seconds,  using GeSHi 1.0.8.4

or maybe calling twice or more my engine function :s

MickArea · by **MickArea** » Mon Mar 09, 2009 10:47 am

a good news for me, using surfaceview solve the problem with the " GC freed x objects/ y bytes in z ms "

MrSnowflake · by **MrSnowflake** » Mon Mar 09, 2009 12:14 pm

Than what were you doing originally?

MickArea · by **MickArea** » Mon Mar 09, 2009 12:53 pm

originally i used your template :p
the problem for me is due to ondraw() a bad way to draw something :p

now i'm using surfaceview and SurfaceHolder :p

MrSnowflake · by **MrSnowflake** » Mon Mar 09, 2009 1:11 pm

So my template doesn't use a surfaceView? strang hehe

. Needs some updating apparently

.

MickArea · by **MickArea** » Fri Mar 13, 2009 9:33 pm

i don't understand ...

sorry ... my english is poor .... xD

( well, because it's you, i will make a update )

fluidity & FPS

fluidity & FPS

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